Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
HEATING APPARATUS
Document Type and Number:
WIPO Patent Application WO/2012/054986
Kind Code:
A1
Abstract:
There is provided a heating apparatus (2) for heating a fluid. In one aspect, the apparatus (2) comprises a chamber (10) arranged for accommodating a volume of fluid therein and a fluid supply means (15) through which fluid may enter the chamber (10). The heating apparatus (2) further comprises a heating system arranged for heating fluid accommodated within the chamber (10), and, one or more fluid circuits arranged so as to provide fluid communication between at least two regions of the chamber (10) so that, when in use, the thermal differential between the fluid of said regions facilitates one or more thermal convection circuits which, at least in part, promotes the flow of fluid about at least one of the or each fluid circuits.

Inventors:
TUCKER KENNETH JOHN (AU)
Application Number:
PCT/AU2011/001388
Publication Date:
May 03, 2012
Filing Date:
October 28, 2011
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
TUCKER TECHNOLOGIES PTY LTD (AU)
TUCKER KENNETH JOHN (AU)
International Classes:
F24H4/00; F24F13/12; F24H1/44; F24H8/00; F24J2/44; F25B29/00; F28F27/02
Foreign References:
US4777347A1988-10-11
GB561938A1944-06-12
US5060601A1991-10-29
Attorney, Agent or Firm:
ALLENS ARTHUR ROBINSON PATENT & TRADE MARKS ATTORNEYS (Melbourne, Victoria 3000, AU)
Download PDF:
Claims:
The claims defining the invention are as follows:

1. A heating apparatus for heating a fluid, the apparatus comprising: a chamber for accommodating a volume of fluid; fluid supply means by which fluid may enter the chamber; a heating system for heating fluid accommodated within the chamber; one or more fluid circuits arranged so as to provide fluid

communication between at least two regions of the chamber so that, when in use, a thermal differential between the fluid of said regions of the chamber facilitates one or more thermal convection circuits which, at least in part, promotes the flow of fluid about said one or more fluid circuits, wherein said one or more fluid circuits comprise one or more first fluid circuits arranged within the chamber so as to provide for the flow of fluid from one of the regions of the chamber toward the other region.

2. A heating apparatus for heating a fluid, the apparatus comprising: a chamber for accommodating a volume of fluid; fluid supply means by which fluid may enter the chamber; a heating system for heating fluid accommodated within the chamber; one or more fluid circuits arranged so as to provide fluid communication between at least two regions of the chamber so that, when in use, a thermal differential between the fluid of said regions of the chamber is, at least in part, reduced,

duwm A0118742661v2 120179441 wherein said one or more fluid circuits comprise one or more first fluid circuits arranged within the chamber so as to provide for the flow of fluid from one of the regions of the chamber toward the other region.

3. A heating apparatus according to claim 2, wherein said one or more first fluid circuits each comprises a fluid transfer element arranged having an inlet and outlet each associated with respective regions of the chamber so as to provide fluid communication therebetween.

4. A heating apparatus according to claim 2 or claim 3, wherein at least one of said one or more first fluid circuits is a thermosyphon. 5. A heating apparatus according to any one of the preceding claims, wherein the heating system comprises one or more heat supply circuits each providing thermal communication between at least one heat source and the chamber.

6. A heating apparatus according to claim 5, wherein said one or more heat supply circuits comprise at least one assembly of one or more heating elements arranged in thermal communication with the chamber.

7. A heating apparatus according to claim 6, wherein said one or more heating element is/are arranged in thermal communication with one of the regions of the chamber. 8. A heating apparatus according to claim 6 or claim 7, wherein said one or more heating elements is/are arranged substantially within the chamber so as to be immersed within the fluid when contained in the chamber.

9. A heating apparatus according to any one of claims 5 to 8, wherein the or each heat supply circuit is arranged to receive a working fluid containing thermal energy from its respective heat source, the or each heat supply circuit arranged to supply the working fluid to one or more of the heating elements of the respective heat supply circuit.

duwm A011874266lv2 120179441

10. A heating apparatus according to any one of claim 5 to 9, wherein at least one of the or each heat supply circuit is part of a refrigeration circuit.

11. A heating apparatus according to claim 9 or claim 10, wherein the thermal energy of the working fluid is, at least in part, provided by a waste heat source.

12. A heating apparatus according to any one of claims 9 to 11, wherein the working fluid is one of a heated vapour or a heated liquid.

13. A heating apparatus according to any one of the preceding claims, wherein the chamber is substantially cylindrical having an axis substantially aligned with the vertical plane.

14. A heating apparatus according to any one of the preceding claims, wherein at least one of the or each fluid circuit comprises one or more second fluid circuits which may be arranged for removing a quantity of fluid from the chamber for supply to one or more outlets.

15. A heating apparatus according to claim 14, wherein one or more of the second fluid circuits is arranged so that a portion of the quantity of fluid is returned to the chamber.

16. A heating apparatus according to claim 14 or claim 15, wherein the or each second fluid circuit is/are arranged so as to fluidly connect an upper region of the chamber to a lower region of the chamber so that a portion of the quantity of fluid not dispersed is returned to the chamber at the lower region thereof, the flow of the fluid through the or each second circuits being due, at least in part, to the thermal differential of the fluid existing between the upper and lower regions of the chamber.

17. A heating apparatus according to any one of claims 14 to 16, wherein the second set of fluid circuits comprises externally arranged return fluid circuits in the form of one or more ring main fluid circuits which fluidly communicate with one or more fluid dispersal outlets. duwm A011874266lv2 120179441

18. A heating apparatus according to claim 17, wherein each ring main fluid circuit comprises a first end and a second end, the first end of each ring main fluid circuit being fluidly connected with the chamber by way of engagement with an external side wall of an upper region of the chamber, the second end of each ring main fluid circuit being fluidly connected with the chamber by way of engagement with an external side wall of a lower region of the chamber, such that liquid may pass to/from the ring main circuit from/to the chamber.

19. A heating apparatus according to claim 18, wherein the first end of each ring main fluid circuit is arranged having a dimension which is greater than that of the second end so as to assist with increasing the velocity of the liquid or fluid flowing through the respective circuit.

20. A heating apparatus according to any one of the preceding claims, wherein at least one of the one or more fluid circuits comprises one or more third fluid circuits being arranged for removing a quantity of fluid from an upper region of the chamber, and returning the quantity of fluid to a lower region of the chamber.

21. A heating apparatus according to claim 20, wherein a portion of the or each third fluid circuit is arranged in thermal communication with a further fluid or a further heat exchanger system so as to provide thermal energy thereto.

22. A heating apparatus according to any one of the preceding claims, wherein the heating system comprises one or more heat supply circuits arranged so as to each provide thermal communication between at least one heating source and the chamber.

23. A heating apparatus according to claim 22, wherein the or each heat supply circuit is arranged so as to comprise at least one assembly of one or more heating elements arranged in thermal communication with the chamber.

du mA011874266lv2 120179441

24. A heating apparatus according to claim 23, wherein the or each heating elements is arranged in thermal communication with one of said regions of the chamber.

25. A heating apparatus according to claim 23 or claim 24, wherein the or each heating element is arranged substantially within the chamber.

26. A heating apparatus according to any one of claims 22 to 25, wherein the or each heat supply circuit is arranged so as to receive a working fluid containing thermal energy from its respective heat source so as to supply the working fluid to one or more of the heating elements of the respective heat supply circuit.

27. A heating apparatus according to any one of claims 22 to 26, wherein at least one of the or each heat supply circuits is part of a refrigeration circuit.

28. A heating apparatus according to claim 26 or claim 27, wherein the working fluid comprises a heated vapour or a heated liquid whereby the thermal energy of the working fluid is, at least in part, provided by a waste heat source.

29. A heating apparatus according to any one of claims 23 to 28, wherein the or each heating element comprises an immersion coil arranged so as to be immersed within the fluid contained in the chamber.

30. A heating apparatus according to claim 29, wherein each immersion coil is provided with one or more externally disposed heat dispersing elements to increase the rate of heat dispersal to the fluid in the chamber.

31. A heating apparatus according to claim 29 or claim 30, wherein each

immersion coil is arranged so as to be operatively associated with one or more compressor units for providing thermal energy to the chamber.

32. A heating apparatus according to any one of the preceding claims further including a first assembly of one or more heating elements disposed within duwmA011874266lv2 120179441 a first region of the chamber, and a second assembly of one or more heating elements disposed within a second region of the chamber.

33- A heating apparatus according to claim 32, further including a further assembly of one or more heating elements disposed in a further region of the chamber substantially intermediate the first and second regions of the chamber.

34. A heating apparatus substantially as hereinbefore described and with

reference to any one or more of the accompanying Figures.

duwmAOl 1874266 lv2 120179441

Description:
HEATING APPARATUS

Field of the invention

The present invention relates to a heating apparatus for heating a fluid. In one aspect, the invention relates to a heating apparatus for heating a fluid for supply to one or more downstream outlets. In another aspect, the invention relates to a heating apparatus arranged for heating a fluid using heat from a waste heat source. In another aspect, the invention relates to a heating apparatus for use with a refrigeration system.

Background of the invention In this specification, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date part of common general knowledge, or known to be relevant to an attempt to solve any problem with which this specification is concerned. Heating and storing heated liquid (such as water) efficiently can be complex and challenging. Temperature stratification is one common problem that has been observed when heating and maintaining a liquid to a desired

temperature in conventional prior art arrangements. For example, when water is heated, the hottest water rises to the top of the tank due to increasing

temperature and pressure, leaving the cooler water to remain in the bottom region of the tank with lower pressure. In a large tank this can result in a significant temperature differential between the water at the top and bottom portions of the tank. The stratified temperature differential can result in

considerable time and energy (at significant cost) being required for the body of water in the tank to be heated to the desired temperature. Furthermore, considerable additional thermal energy is often required to maintain that temperature.

duwm A011874266lv2 120179441 Typical heating systems generally include one or more heat exchangers which comprise one or more coils made from high thermally conducting materials, and through which a heated gas or liquid is arranged to flow. Such arrangements are often utilised to produce heated water in various types of hot water storage systems. For example, in some prior art heat exchangers, heating coils, containing a working fluid, are wrapped or wound about the external surround of a storage tank. The coils can each be covered with an insulation material and/or enveloped with a further insulative shell. In some applications, such systems have been shown to be deficient, as adhesive commonly used on the coils often melts, resulting in inefficient transfer of thermal energy. Furthermore, additional energy is often expended due to the need in some prior art devices to employ specific pumping mechanisms to pump heated fluid throughout the system resulting in further increases in unnecessary energy expenditure.

Summary of the invention According to a first aspect of the present invention, there is provided a heating apparatus for heating a fluid, the apparatus comprising: a chamber for accommodating a volume of fluid; fluid supply means by which fluid may enter the chamber; a heating system for heating fluid accommodated within the chamber; one or more fluid circuits arranged so as to provide fluid communication between at least two regions of the chamber so that, when in use, a thermal differential between the fluid of said regions of the chamber facilitates one or more thermal convection circuits which, at least in part, promotes the flow of fluid about said one or more fluid circuits, wherein said one or more fluid circuits comprise one or more first fluid circuits arranged within the chamber so as to provide for the flow of fluid from one of the regions of the chamber toward the other region.

duwmA0118742661v2 120179441 According to a second aspect of the present invention, there is provided a heating apparatus for heating a fluid, the apparatus comprising: a chamber for accommodating a volume of fluid; fluid supply means by which fluid may enter the chamber; a heating system for heating fluid accommodated within the chamber; one or more fluid circuits arranged so as to provide fluid communication between at least two regions of the chamber so that, when in use, a thermal differential between the fluid of said regions of the chamber is, at least in part, reduced, wherein said one more fluid circuits comprise one or more first fluid circuits arranged within the chamber so as to provide for the flow of fluid from one of the regions of the chamber toward the other region.

Embodiments of each of the above described aspects of the invention may include one or more of the following arrangements: In a preferred embodiment, the chamber is substantially cylindrical having an axis substantially aligned with the vertical plane. In this embodiment, two of said regions oppose one another. For example one of said regions may be an upper region of the chamber, and the other of said regions may be a lower region of the chamber. This general arrangement of the chamber will be referred to throughout the description of the embodiments of the present invention which follow. However, it will be appreciated that the chamber may be arranged in many number of ways in order to benefit from the principles of the invention.

The chamber may be arranged so as to be thermally insulated. In one embodiment of this arrangement, the chamber may be arranged so as to be substantially surrounded with a thermally insulated substrate so as to thermally isolate the chamber from ambient atmosphere.

duwm A0118742661v2 120179441 In one embodiment, the one or more first fluid circuits is or are arranged within the chamber so as to provide for the flow of fluid from one of the regions (upper region) of the chamber toward the other region (lower region).

In some embodiments, the or each first fluid circuit may comprise a fluid transfer element arranged having an inlet and an outlet each being associated with respective regions of the chamber so as to provide fluid communication

therebetween. The fluid transfer element may comprise an elongate hollow conduit arranged within the chamber so that fluid may flow between the regions of the chamber. In one embodiment, at least one of the or each fluid circuit(s) may comprise a thermosyphon which is arranged to fluidly connect respective regions of the chamber.

The chamber may be provided with at least two (in most embodiments four) internally arranged thermosyphons for heating liquid in an upper region of the chamber and allowing for the transfer of the heated liquid toward a lower region of the chamber such that the temperature differential and pressure between the liquid in the upper and lower regions of the chamber reduces by way of a thermal convection circuit. Therefore, the transfer of liquid between the upper and lower regions of the chamber occurs via the internal thermosyphons. As the temperature and pressure of the liquid in the upper region of the chamber increases, warmer liquid is pushed, via the internal thermosyphons in the form of tubes, toward the cooler liquid residing in the lower region of the chamber thus creating a 'mix-down' of the overall temperature of the liquid in the chamber. By feeding liquid in the upper region of the chamber toward the lower region of the chamber, the temperature of the liquid in the chamber becomes mixed so as to approximate a substantially uniform temperature substantially throughout the chamber.

As a result of the above described arrangement, the liquid in the chamber is thought to be able to heat significantly faster than conventional heating systems.

duwmA0118742661v2 120179441 In this regard, as heated liquid in the chamber rises toward an upper region of the chamber, rather than being directed to side regions of the chamber (and then downwards), the liquid is instead able to escape rapidly through the internal thermosyphons toward a lower region of the chamber. Accordingly, the liquid within the chamber is encouraged, or in some embodiments forced, to mix continually such that the temperature of the liquid as a whole remains

substantially uniform as it is heated. This process occurs more rapidly as the temperature and pressure of the liquid in the chamber increases. In one embodiment, the developing internal pressure is thought to significantly influence, at least in part, the rate of development of the thermal convection circuit thereby increasing the rate at which the temperature rises. Thus, it will be appreciated that the chamber is provided of suitable and sufficient construction so as to withstand the relatively high internal pressures which result as compared with conventional arrangements. In one embodiment, at least one of the or each fluid circuit(s) comprises one or more second fluid circuits which may be arranged for removing a quantity of fluid from the chamber for supply to one or more outlets. Such fluid circuit(s) is/are arranged so that a portion of the quantity of fluid is returned to the chamber. In this embodiment, the or each second fluid circuit is/are arranged so as to fluidly connect an upper region of the chamber to a lower region.

Accordingly, a portion of the quantity of fluid not dispersed is returned to the chamber at a lower region thereof. The flow of the fluid through such circuits is due, at least in part, to the thermal differential of the fluid existing between upper and lower regions of the chamber. At least one of the or each second fluid circuit(s) may be arranged to include the one or more outlets through which fluid removed from the chamber may be provided thereto. In a further embodiment, at least one of the or each outlet(s) may be arranged in fluid communication with a respective fluid dispersal unit. Such fluid dispersal units may include, but are not limited to, faucets, shower heads, sprinklers, sprinkler assembly or the like.

duwm A0118742661v2 120179441 In one embodiment, the second set of fluid circuits may comprise externally arranged return fluid circuits in the form of one or more ring main fluid circuits which fluidly communicate with one or more fluid dispersal outlets such as faucets, shower heads, fluid reticulation/distribution networks or assemblies, sprinklers or sprinkler assemblies or the like.

Each ring main fluid circuit comprises a first end and a second end. The first end of each ring main fluid circuit may be fluidly connected with the chamber by way of engagement with an external side wall of an upper region of the chamber. The second end of each ring main fluid circuit may be fluidly connected with the chamber by way of engagement with an external side wall of a lower region of the chamber. It will be appreciated that the engagement between the first second ends of each ring main fluid circuit, and the respective regions of the chamber, is such that liquid may pass to/from the ring main circuit from/to the chamber. It will also be appreciated that various such engagements for achieving such flows will be readily known to the skilled person.

The first end of each ring main fluid circuit may have a diameter which is greater than the diameter of the second end so as to assist with increasing the velocity of the liquid or fluid flowing through the respective circuit.

In one embodiment, the fluid supply means may be arranged in fluid communication with a source of the fluid. The fluid supply means may be arranged so that at least a portion of the fluid flowing therein is in thermal communication with the fluid contained within the chamber.

In another embodiment, the fluid supply means may comprise a further fluid transfer element arranged so as to provide fluid communication between the source of the fluid and a lower region of the chamber while providing thermal communication between the further fluid transfer element and an upper region of the chamber.

duwm A0118742661v2 120179441 In one embodiment, a portion of the further fluid transfer element may be arranged internally of the chamber. Furthermore, the further fluid transfer element may be arranged to extend substantially along the length of the chamber.

The chamber may further include an outlet such as a sump drain or similar arranged with the chamber so that fluid/liquid may be drained therefrom. In one embodiment, the outlet is arranged at or near the lower region of the chamber.

In another embodiment, at least one of the one or more fluid circuits comprises one or more third fluid circuits which may be arranged for removing a quantity of fluid from an upper region of the chamber, and returning the quantity of fluid to a lower region of the chamber.

A portion of the or each third fluid circuit may be arranged in thermal communication with a further fluid or a further heat exchanger system so as to provide thermal energy thereto.

In one embodiment, the heating system comprises one or more heat supply circuits which may be arranged so as to each provide thermal communication between at least one heating source and the chamber.

The or each heat supply circuit may be arranged so as to comprise at least one assembly of one or more heating elements arranged in thermal

communication with the chamber. Furthermore, the or each heating element(s) may be arranged in thermal communication with one of said regions of the chamber.

In another embodiment, the or each heating element(s) may be arranged substantially within the chamber.

The or each heat supply circuit may be arranged to receive a working fluid containing thermal energy from its respective heat source. In this embodiment, the or each heat supply circuit is arranged to supply the working fluid to one or more of the heating elements of the respective heat supply circuit.

duwm A0118742661v2 120179441 The or each heating element may be arranged to provide for the transfer of thermal energy from the working fluid to the fluid contained within the chamber.

In one embodiment, at least one of the or each heat supply circuits may form part of a refrigeration circuit.

The working fluid may be a heated vapour or a heated liquid. In one embodiment, the thermal energy of the working fluid is, at least in part, provided by a waste heat source.

The heating element(s) may comprise immersion coils which are arranged to be immersed within the fluid contained in the chamber. The arrangement of the immersion coils is such that they are able to withstand relatively higher pressure and temperatures than conventional prior art heating elements.

In one embodiment, each immersion coil may be provided with one or more externally disposed heat dispersing elements to increase the rate of heat dispersal to the fluid in the chamber.

Each immersion coil may be arranged to be operatively associated with various known compressor units for providing thermal energy to the chamber. Furthermore, the immersion coils may be arranged to operate with known suitable refrigerant gases when respective heat supply circuits are arranged with a refrigeration circuit.

In one embodiment, the heating apparatus of the first or second aspects may include a first assembly of one or more heating elements disposed within a first region of the chamber, and a second assembly of one or more heating elements disposed within a second region of the chamber. In another

embodiment, a further assembly of one or more heating elements may be disposed in a further region of the chamber substantially intermediate the first and second regions of the chamber.

In one embodiment, the present invention provides a heat exchanger arranged for transferring heat from an independent compressor, or other waste duwm AO 118742661 v2 120179441 heat source such as a refrigeration process, to a fluid such as a liquid. The heated liquid can then be harnessed for use in an operational heat pump. Efficiencies of variations of arrangements of this type will vary based on the type of compressor and their measured Coefficient Of Performance (COP). In one embodiment, the chamber of the heating apparatus includes four internally arranged thermosyphons substantially evenly spaced within the chamber, and two external ring main return fluid circuits which are positioned on opposite external sides of the chamber. The two ring main return fluid circuits are preferably maintained in an open configuration such that heated fluid can be dispensed through one or more outlets. In another embodiment, the two ring main fluid circuits may be located on or about an external side wall of the chamber.

Where embodiments of the present invention are to be installed in situations or environments where no waste heat is readily available (for example for providing hot water in existing residential applications), independent compressors may provide the heated working fluid required for circulation within the immersion coils. In some arrangements, the opportunity for providing cooling (such as for example air conditioning or a cool room for storage) is afforded in addition to the heating function when arrangements of the present invention are installed. Additionally, arrangements of the present invention which include one or more ring main fluid circuits, hydronic heating or swimming pool heating can be also be provided.

One or more control devices may be operatively associated with any of the fluid circuits so as to selectively permit the fluid to flow through the fluid circuits in response to sensed temperature and pressure values obtained from the fluid within the chamber. The control devices may be arranged to process the temperature and pressure data so as to control the desired thermal and pressure levels in any one or more secondary chambers which may contain other types of fluid to be heated, such as for example cleaning chemicals.

duwmA0118742661v2 120179441 In another embodiment, any of the first, second and third fluid circuits may be arranged to be an operative heat exchanging ring main which may be thermally associated with a secondary heat exchanger. In this arrangement, heated fluid in the operative heat exchanging fluid circuit flows by way of a conduit immersed within the fluid of a chamber of a second heat exchanger to heat the fluid provided therein. An example of this arrangement is an external storage chamber which serves to heat cleaning chemicals in an abattoir.

According to another aspect, there is provided a heat exchanger, hot water and/or heating system, arranged in accordance with any of the embodiments of the present invention described herein, which is used to transfer heat from one medium (such as a fluid) to another (such as a liquid to be heated) while maintaining separation between both mediums, and which provides for the thermal circulation (or self-pumping) of the flow of the liquid to be heated through one or more fluid circuits. In a further aspect, there is provided a heat exchanger which may be arranged with any one or more embodiments of the first or second aspects of the present invention for transferring heat from an independent compressor, or other waste heat source such as a refrigeration process, to a fluid such as a liquid.

According to this aspect, the heated liquid can be harnessed for use in an operational heat pump.

According to a further aspect of the present invention, there is provided a self-pumping heat exchange system which may be arranged with any one or more of the embodiments of the first or second aspects of the present invention.

According to another aspect of the present invention, there is provided a thermal pump arrangement which may be arranged with any one or more of the embodiments of the first or second aspects of the present invention.

According to yet another aspect of the present invention, there is provided a heat exchange system incorporating any one or more embodiments of the above described aspects of the present invention, which may be particularly suited where duwm A0118742661v2 120179441 both heated water and refrigeration are required. Various embodiments of this aspect allow for the continual transfer of waste heat from various types of compressors for utilisation as required for heating and cooling purposes.

Brief description of the drawings Embodiments of the invention will now be further explained and

illustrated, by way of example only, with reference to any one or more of the accompanying drawings in which:

Figure 1 shows an elevation view of the exterior of a heat exchanger according to one embodiment of the present invention; Figure 2 shows a schematic elevation view showing the arrangement of the internal components of the embodiment of the heat exchanger shown in Figure 1;

Figure 3 shows a schematic elevation view showing the arrangement of the internal components of the embodiment of the heat exchanger shown in Figure 1;

Figure 4A shows a plan view of the embodiment of the heat exchanger shown in Figure 1;

Figure 4B shows a cross section view of section A-A of the embodiment of the heat exchanger shown in Figure 1;

Figure 4C shows a cross section view of section B-B of the embodiment of the heat exchanger shown in Figure 1; Figure 4D shows a cross section view of section C-C of the embodiment of the heat exchanger shown in Figure 1;

Figure 4E shows a cross section view of section DD of the embodiment of the heat exchanger shown in Figure 1;

Figure 4F shows a cross section view of section E-E of the embodiment of the heat exchanger shown in Figure 1;

duwmA011874266lv2 120179441 Figure 4G shows a cross section view of section F-F of the embodiment of the heat exchanger shown in Figure 1; and,

Figure 5 shows a cross section view of one embodiment of an immersion coil used in accordance with the present invention. Detailed description

With reference to Figure 1, there is shown one embodiment of a heating apparatus 2 for heating a fluid such as liquid water. The heating apparatus 2 includes a tank 6 which is arranged to define a chamber 10 within which a volume of the fluid may be accommodated. Fluid may enter the chamber 10 by way of a fluid supply means 15.

The chamber 10 of the heating apparatus 2 includes a first region and a second region which occupies respective volumes at opposite ends of the chamber. For the arrangement shown, where the axis Y of the tank 6 is aligned substantially with the vertical plane, the first region comprises upper region 12 of the chamber 10, and the second region comprises lower region 13 of the chamber.

The heating apparatus 2 further includes a heating system arranged for heating the fluid occupying the chamber 10 when the heating apparatus 2 is in operation. For the embodiment shown in Figures 1 to 3, the heating system includes a first assembly 8 of five (5) heating elements such as immersion coils 14 provided at the upper region 12 of the chamber 10, and a second assembly 9 of five (5) immersion coils 14 provided in the lower region 13 of the chamber 10.

Each of the immersions coils 14 is arranged so as to be in fluid

communication with one or more heat supply circuits 16 which supply a heated fluid (typically referred to as a working fluid), such as a heated vapour or gas, from a heat source 30 (such as from one or more compressor units or a waste heat source). The number of immersion coils 14 arranged within the chamber 10 can

duwmA01l874266lv2 120179441 be varied depending upon the particular application the heating apparatus 2 is to be arranged for.

The heating apparatus 2 further includes one or more fluid circuits arranged so as to provide fluid communication between the upper region 12 and the lower region 13 of the chamber 10. Therefore, when the heating apparatus 2 is in operation, the thermal differential between the fluid of the regions 12, 13 of the chamber 10 facilitates one or more thermal convection circuits which, at least in part, promotes the flow of fluid about at least one of the fluid circuits.

Furthermore, one or more fluid circuits may be arranged so that the thermal differential between the fluid of the upper 12 and lower 13 regions of the chamber 10 is, at least in part, reduced. For the embodiment shown, at least three different arrangements of fluid circuits are provided as will be discussed in further detail below.

It will be appreciated that embodiments of the heating apparatus 2 described herein can be adapted and arranged to heat many different types of fluids in the chamber 10 depending on the particular application the heating apparatus 2 is to be arranged for. Accordingly, the principles of the operation of the heating apparatus 2 of the present invention can be applied to many different applications which exploit the performance benefits of the apparatus. For ease of explanation, the following description will concern the specific application to which the embodiments of the invention shown in the Figures relates, ie. the heating of liquid water. Accordingly, the fluid accommodated within the chamber 10 for the purposes of the present description will be referred to hereinafter as liquid water. Each of the components which comprise the embodiments of the present invention featured in the Figures will be discussed in turn below.

The heating system of the heating apparatus 2 comprises one or more heating elements such as immersion coils 14. The heating system may include one or more assemblies which comprise any number of immersion coils 14. As

duwm A0118742661v2 120179441 previously stated, two (2) assemblies (first 8 and second 9) are provided with each comprising four (4) or five (5) immersion coils 14. Each immersion coil 14 is arranged so as to be immersed within the water contained within the chamber 10 so that the water can readily absorb the thermal energy provided by the heated working fluid (such as a heated vapour or gas) which flows within each immersion coil 14. Each immersion coil 14 may be orientated in a configuration which extends substantially inwards towards the axis Y of the chamber 10, as shown in Figures 2, 3, and 4B. The number of immersion coils 14 used in each assembly 8, 9 may change depending on the specific heating application. Four immersion coils 14 in each assembly 8, 9 have been shown to be sufficient for use in a domestic embodiment (see the data relating to the example presented further below).

The first 8 and second 9 assemblies of immersion coils 14 are arranged in fluid and/or thermal communication with a respective heat supply circuit 16 about which the working fluid flows. Each heat supply circuit 16 supplies the working fluid to its respective assembly of immersion coils 14 for heating the water in the chamber 10. Each heat supply circuit 16 comprises a supply feed 18 which provides the heated working fluid to the respective assembly (8, 9) of immersion coils 14, and a return line 22 which returns the working fluid (in a cooler thermal state) to the heat source 30.

The heated working fluid is provided to the respective immersion coils 14 by way of a manifold assembly 26 which receives the working fluid via the supply feed 18. The manifold assembly 26 is further arranged to allow the spent working fluid (once the fluid has passed through each of the respective immersion coils 14) to exit the system via the return line 22 so as to allow the working fluid to be returned to the heat source 30. In one embodiment, the manifold assembly 26 is generally arranged so as to thermally separate the incoming heated working fluid (being fed to the immersion coils 14) from the cooler working fluid exiting the immersion coils 14 and enroute back to the heat source 30.

duwmA0118742661v2 120179441 It will be appreciated that the immersion coils 14 may be arranged to be operatively associated with various known compressor units for providing thermal energy to the chamber 10. Furthermore, the immersion coils 14· may be arranged to operate with any known suitable refrigerant gases when respective heat supply circuits 16 are arranged with a refrigeration circuit.

The immersion coils 14 may be mounted to the tank 6 by way of one or more mounting plates 28 which are mounted to the sidewall of the chamber 10.

With reference to Figure 2, mounting plate 28a is located in the side wall of the upper region 12 of the chamber 10 so as to mount the first assembly 8 of immersion coils 14. A further mounting plate 28b is provided in the side wall of the lower region 13 of the chamber 10 (directly below the mounting plate 28a) for mounting the second assembly 9 of immersion coils 14 thereto. It will be appreciated that a variety of ways could be employed to mount or secure the respective assemblies of immersion coils 14 to the side wall of the chamber 10. In some embodiments, the immersion coils 14 are configured so as to be as thermally efficient as possible. With reference to Figure 5, each immersion coil 14 consists of an outer sleeve 140 which surrounds a conduit 98. The conduit 98 and outer sleeve 140 may each be made from copper (or other high thermally conducting material such as duplex stainless steel or similar alloys) with a solid mass of annealed pure nickel 102 or other highly thermally conductive material

(or in some embodiments, materials which may be chemically compatible with the conduit and sleeve) provided therebetween. The outer surface of the sleeve 140 may be provided with a heat dispersal system such as an arrangement of fins so as to assist in the exchange of thermal energy between the immersion coils 14 and the water in the chamber 10.

It will be appreciated that each of the assemblies 8, 9 of immersion coils 14 may be arranged with a flow control mechanism which allows the flow of the working fluid to one or more of the respective immersion coils 14 to be adjusted or controlled depending on the operational characteristics/strategy required. In such arrangements, the flow of working fluid to each immersion coil 14 may be duwm A0H8742661v2 120179441 independently controlled so as to vary the degree of heating required. The control of the flow control mechanism can be performed by a suitable processing until which serves to administer the appropriate controlling instructions to manage the required operational requirements depending on the application the heating apparatus 2 is arranged for. It will be appreciated that the operation of such a flow control mechanism may be informed by the temperature or pressure levels of the water in the chamber when sampled and processed by suitable sensor and data acquisition equipment.

One or both of the heat supply circuits 16 may source the heated working fluid from a source of waste heat (for example, thermal energy removed from a cool room). In one arrangement, the heat supply circuit 16 may be arranged as part of a refrigerant gas circuit of a cooling system. The cooling system can be any type of system which generates waste heat. For example, the cooling system may be one already operating in a commercial environment. The heat supply circuit(s) 16 may also be powered by remote compressors depending on the particular application.

With reference to the embodiment of the heating apparatus 2 shown in Figures 1 to 3, there is provided a first set of fluid circuits arranged within the chamber 10 for fluidly connecting the upper 12 and lower 13 regions of the chamber. The first set of fluid circuits comprises four (4) thermosyphons 34 which are arranged within the chamber 10 for providing fluid communication between the upper 12 and lower 13 regions of the chamber 10.

The thermosyphons 34 aid in the transfer of heated fluid from the upper region 12 of the chamber 10 to the lower region 13 of the chamber. Each thermosyphon 34 comprises a fluid transfer element generally being of a hollow elongate section (circular conduit sections are shown in the Figures) made from a stable, corrosion resistant, high thermally conductive material such as duplex stainless steel or similar alloy. Each thermosyphon 34 is welded to the wall of the chamber 10 with welded brackets formed from the same material as that of the thermosyphon. The thermosyphons 34 are each arranged within the chamber 10 duwmA011874266lv2 120179441 in an orientation which is aligned substantially parallel with the axis of the chamber 10 so that the upper 12 and lower 13 regions of the chamber 10 are fluidly and thermally associated with one another. The thermosyphons 34 are generally arranged equispaced about the axis Y of the chamber 10, and parallel relative to one another as shown in Figures 4C, 4E, and 4F.

Each thermosyphon 3 therefore functions so as to transfer the heated water (typically at higher temperature and pressure) from the upper region 12 of the chamber 10 towards the lower region 13 of the chamber 10 where

substantially cooler water resides. The transfer of liquid (which can be rapid) between both regions (12 and 13) is thought to occur as a result of the

temperature and pressure differentials of the water between the upper 12 and lower 13 regions of the chamber 10 seeking to stabilize and attain thermal stability (equilibrium). In some instances, the turbulence of the mixing water inside the chamber 10 can be such that it is audible outside the tank 6. In operation, this effect has been observed to facilitate a rapid increase in temperature to around 93 degrees Celsius with the pressure at around 800kPa. At high temperature and pressure levels, the water in the chamber 10 appears to circulate by way of thermal convection thereby requiring a reduced amount of energy to maintain the temperature and requiring little to no pumping to continue the circulatory flow. As mentioned, the rate of the heating of the water can be rapid as there is an increased rate of mixing down of the heated water from the upper region 12 of the chamber 10 with the liquid from the lower region 13 due to the operation of the thermosyphons 34. In one embodiment, and without being bound by theory, the developing internal pressure is thought to significantly influence, at least in part, the rate of development of the thermal convection circuit which serves to increase the rate at which the temperature of the liquid in the chamber rises.

Having regard to one embodiment, the compressors are arranged to shut down when the pressure within the chamber 10 reaches a pressure in the order of 800kPa by way of signals received from one or more pressure limiting valves. The thermosyphons 34 may continue the circulation of the liquid at around 93 degrees

duwm AO 118742661 v2 120179441 Celsius in a thermal convection based cycle that has been shown to avoid the need for an independent pumping means.

It will be appreciated that the thermosyphons 34 could be arranged in any number of ways provided they fluidly connect the upper 12 and lower 13 regions of the chamber 10. According to one arrangement, the ends of the

thermosyphons 34 may be arranged to be off different dimensions to adjust the velocity of the fluid flowing therethrough.

The heating apparatus 2 includes a second set of fluid circuits (generally refereed to as ring main fluid circuits) configured in an open configuration for fluidly connecting the upper 12 and lower 13 regions of the chamber 10, and arranged to supply heated water from the chamber 10 to one or more outlets 48. With reference to Figure 3, ring main fluid circuits 40, 44 are provided which include respective upstream connecting sections 52, 56 which fluidly connect the respective circuit to the chamber 10 so as heated water may be received for transfer throughout the circuit's remaining sections (for example, conduit section 41 and supply conduit section 60 for the case of ring main fluid circuit 40). The ring main fluid circuits 40, 44 each include at least one respective supply conduit sections 60, 64 to which the outlets 48 are arranged in fluid communication therewith so as to supply a respective downstream destination. For the embodiment shown in Figure 3, each ring main fluid circuit 40, 44 shares a return conduit 68 which fluidly connects both ring main circuits back with the chamber 10 at substantially the lower region 13 of the chamber 10 by way of connecting section 70, thereby returning undistributed water back into the chamber for heating. It will be appreciated that each ring main fluid circuit 40, 44 may be arranged with its own return conduit thereby ensuring that each circuit is independent from the other.

Each ring main fluid circuit 40, 44 effectively operates similar to the operation of the first set of fluid circuits described above (the set of four thermosyphons 34) in that there is a fluid connection between the upper 12 and

duwm A011874266lv2 120179441 lower 13 regions of the chamber 10 (between which a thermal differential typically exists). However, the substantial difference between both sets of fluid circuits is that the ring main fluid circuits 40, 44 are arranged in an open configuration to transfer the heated water from within the chamber 10 to remote oudets 48 downstream of the upper region 12 of the chamber 10. At one or more oudets 48 along the ring main fluid circuits 40, 44, fluid dispersal devices such as taps or faucets may be provided. The outlets 48 may fluidly connect with respective inlets to one or more distribution or reticulation networks which serve to distribute the heated water to any number of further downstream dispersal points. To afford operational control of the distribution of the heated water to the oudets 48, the ring main fluid circuits 40, 44 may be arranged to be selectively opened and closed as required in response to temperature and pressure levels of the water within the chamber 10. The selective control of the fluid flows through one or both ring main fluid circuits 40, 44 may be performed using any known fluid flow control devices in the art such as fluid flow control valves. It will be appreciated that such devices may need to be selected based on the nature of the fluid flowing through the respective fluid circuits.

It will be appreciated that the temperature and pressure levels of the water in the chamber 10 may be monitored by appropriate temperature and pressure transducer units known in the art. Temperature and pressure data may be processed by a suitable processing unit so that the control of the water flow through the ring main fluid circuits 40, 44 can be conducted according to any desired or predetermined operating strategy. It will be appreciated that such operating strategy may vary depending on various factors - including the nature of the application the heating apparatus 2 has been arranged for, the nature of the oudets 48 and the required delivery/distribution response sought, and the nature of the fluid to be heated in the chamber 10. It will be appreciated that one or more of the conduit sections forming each of the ring main fluid circuits 40, 44 may comprise temperature and/or pressure sensors which informs the processing unit.

duwmA0118742661v2 120179441 One or both ring main fluid circuits 40, 44 may arranged so as to

operatively associate with a chamber of a further heating apparatus. In this arrangement, the fluid circuit fluidly connects both chambers so as to promote thermal efficiencies in a larger scale heating arrangement. Fluidly connecting both chambers may therefore assist in the promotion of convection circuits between the chambers thereby assisting with the circulation of flow (promoting rapid heating of the relevant fluids) between chambers and, in some arrangements, avoiding the necessity for expensive independent pumping devices. It will be appreciated that arrangements of this nature could be developed across a number of chambers. The ring main fluid circuits may also be arranged so as to provide heated fluid to one or more heating elements (such as immersion coils) which may be immersed in a chamber of a further heating apparatus in accordance with the present invention. For example, the chamber of the further heating apparatus may be arranged for accommodating a different type of fluid such as for example a chemical solution or a gas which may have specific heating requirements (possibly for safety reasons for example). In such arrangements, different types of fluids can be appropriately heated, and maintained at a specific temperature as required, by the transfer of thermal energy from the heated water flowing through the respective ring main fluid circuits. The one or more fluid circuits of the heating apparatus 2 may include a third set of fluid circuits (generally referred to as auxiliary fluid circuits) arranged in a closed loop configuration with the chamber 10. Such auxiliary fluid circuits may be arranged having a portion of the circuit which operates as a heat exchanger in association with a further chamber containing a further fluid to be heated.

With reference to Figure 3, an auxiliary fluid circuit 72 is provided which sources heated water from the upper region 12 of the chamber 10 by way of connecting section 76. The auxiliary fluid circuit 72 carries the heated water through a conduit 80 which is arranged within a further chamber 84 defined by a second tank 88. The auxiliary fluid circuit 72 is therefore arranged so as to duwm A0118742661v2 120179441 provide thermal energy to the further chamber 84 for heating its contents. The auxiUary fluid circuit 72 is completed by way of a return conduit section 92 which fluidly connects the auxiliary fluid circuit 72 to the lower region 13 of the chamber 10 by way of connecting section 93. As described above in relation to the ring main fluid circuits 40, 44, the auxiliary fluid circuits may be arranged so fluid flow therethrough may be selectively controlled. As such, the auxiliary fluid circuit 72 may be arranged so as to be selectively opened and closed in response to temperature and pressure values of the heated water within the chamber 10 as determined using known temperature/pressure sensors. Similarly, one or more of the conduit sections forming the auxiliary fluid circuit 72 may comprise temperature and/or pressure sensors which informs a processing system arranged to operate the fluid circuit as desired.

As shown in the Figures, the ring main fluid circuits 40, 44, and auxiUary fluid circuit 72, are generally of a much greater length than the first set of fluid circuits (ie. the thermosyphons 34). Furthermore, it wiU be appreciated that the sizing of the sections which form the various fluid circuits may be arranged so as to improve the velocity flows within the respective circuits. In this regard, the dimensions of downstream transfer or conduit sections may be smaUer than their upstream counterparts. With reference to ring main fluid circuit 40, return conduit section 68 may, for example, comprise a conduit section having a diameter substantiaUy smaUer than either of conduit sections 41 and 60.

Furthermore, conduit section 41 may comprise a conduit section having a diameter larger than either of supply conduit section 60 and return conduit section 68. By way of a practical example, in one embodiment, the diameter of the first conduit section 41 of the ring main fluid circuit 40, beginning at the outlet at the top of tank 6, may have a section diameter of approximately 50mm. The second or supply conduit section 60 of the ring main circuit 40 (which is connected to the first conduit section 41) may have a section diameter of approximately 35mm. Accordingly, the shared return conduit section 68 of the

duwm A0118742661v2 120179441 ring main fluid circuits 40, 44 may have a section diameter of approximately 25mm.

Therefore, the variance of section dimensions allows the fluid flowing through the respective circuits to increase in velocity. Therefore, the velocity of the fluid flow at, for example, connecting section 70, may be substantially greater than that of the fluid when flowing through conduit section 41. As such, due to the convection circuit established by the temperature differential between the upper 12 and lower 13 regions of the chamber 10, and the reduction in the section diameters of downstream conduits of the respective fluid circuits, the need for any independent circulating means or pump to actively circulate fluid through the circuits can be largely avoided.

The chamber 10 of the heating apparatus 2 further includes a fluid supply means 15 which is operatively connected to a source of fluid so as the chamber 10 may be filled with water for heating. For the embodiment shown in the Figures, the fluid supply means 15 comprises an inlet 17 region provided at the top of the tank 6 and is typically located at or near an internal sidewall of the chamber 10 diagonally opposite one of the connecting sections 52, 56 of respective ring main fluid circuits 40, 44. The fluid supply means 15 further comprises a fluid transfer conduit 94, arranged internal of the chamber 10, which has an end 19 through which fluid may disperse into the chamber 10 at or near the lower region 13. In a preferred embodiment, it will be readily understood that fluid transfer conduit 94 feeds relatively colder fluid into the chamber 10.

The chamber 10 further includes a sump drain arrangement 120 or similar at the lower region 13 of the tank 6 so that liquid may be drained from the chamber 10 such as for service/maintenance purposes. Typically, the sump drain arrangement 120 includes a tap 130 and a sump plug 145. It will be appreciated that one or more such sump drain arrangements may be provided at other locations around the chamber 10 depending on the specific application the heating apparatus 2 is to be arranged for and the specific environment the chamber is to reside within. duwmA011874266lv2 120179441 For the arrangement shown, the fluid transfer conduit 94 is arranged in thermal communication with at least the upper region 12 of the chamber 10 (and indeed is in thermal communication with a substantial portion of the water in the chamber 10) so as the incoming (cooler) water may be heated as it flows toward end 19 of the fluid transfer conduit 94. The fluid transfer conduit 94 is further arranged at or near one of the thermosyphons 34 (as shown in Figures 4C, 4D, 4E and 4F) so as to provide additional heating to the incoming liquid as it travels through the fluid transfer conduit 94 towards the lower region 13 of the chamber 10. It will be appreciated that the flow of fluid through the fluid transfer conduit 94 may be arranged so to be actively controlled thereby controlling the

introduction of incoming fluid.

In some instances, it may be required to inject discrete amounts of thermal energy to 'top-up' the thermal energy in the chamber 10. When such occasional top-up energy is required, one or more compressor units, or a designated waste heat source, can provide the additional amount of thermal energy required. In some arrangements, one or more electric immersion elements 106 (shown in Figure 4E) can alternatively provide the required top-up of thermal energy at times or in applications where noise from the compressor units is unacceptable. With the use of appropriate materials to optimise insulation and conductivity, embodiments of the heating apparatus 2 described herein are able to operate, once started, with minimal top-up energy.

The chamber 10 operates under high pressure and may require one or more pressure relief valves 110 in order to ensure the integrity of the structure of the tank 6 is not compromised. For the embodiment shown in the Figures, the pressure relief valves 110 are located in the upper region 12 of the chamber 10. It will be appreciated that various pressure relief arrangements may be employed anywhere about the chamber 10 so as to ensure the tank 6 is not unduly stressed. In the preferred embodiment, the chamber 10 includes an arrangement of four pressure relief valves 110. Such systems may included automated arrangements involving known pressure sensing equipment which can actuate pressure relief

duwmAOl 18742661 v2 120179441 mechanisms once undesirable pressure (or indeed temperature) levels in the chamber 10 are detected. Systems of this nature may be controlled by a suitable processing unit which may be programmed in accordance with certain operational requirements pending the application the heating apparatus 2 is to be arranged for.

Furthermore, it will be appreciated that pressure transducers may be used at various locations to monitor pressure levels of the fluid/liquid within the heat supply circuits 1 and/or the other fluid circuits (namely, ring main fluid circuits 40, 44, and auxiliary fluid circuit 72) in the system.

During operation, the fluid in the chamber 10 can be heated to significantly high temperatures by virtue of the working fluid in the immersion coils 14 operating at high temperatures. Accordingly, a thermometer 114 or like

temperature sensing device is arranged substantially intermediate the upper 12 and lower 13 regions of the chamber 10 in order to monitor the temperature levels of the water in the chamber 10. It will be appreciated that any number of thermometers may be employed at any number of locations within or about the chamber 10 in order to monitor the temperature levels. It will also be appreciated that thermometers may be used at various other locations to monitor temperature levels of the working fluid such as within the heat supply circuits 16 and/or the other fluid circuits (namely, ring main fluid circuits 40, 44, and auxiliary fluid circuit 72).

In some applications, the chamber 10 may be required to accommodate hard water. In such instances, a sacrificial anode 118 may be positioned

intermediate the upper 12 and lower 13 regions of the chamber 10. It will be appreciated that the anode 118 may be placed at any position within the tank 6 in order to minimise corrosive effects.

It will be appreciated that the heating apparatus 2 of the present invention may be arranged for use in many different applications. According to one example, the heating apparatus 2 may be arranged for use in the food industry

duwm A0118742661v2 120179441 where one or more cool rooms may be provided where a temperatxire in the order of 3 degrees Celsius is required to be maintained. The refrigerant gas circuit of such a cool room generates a significant amount of heat in order to maintain a temperature level of this order. Under normal operating conditions, the refrigerant gas in the refrigerant gas circuit is generally cooled by passing the refrigerant gas through a condenser where it is cooled and condensed into a liquid by passing cool air across tubes through which the gas flows. However, by passing the refrigerant gas through the immersion coils 14, and by including the immersion coils in the refrigerant gas circuit, the heat which would otherwise be lost to the atmosphere in the condenser can instead be utilised and recovered for use with arrangements of the heating apparatus 2 of the present invention. The heating apparatus 2 may then effectively operate as a heat pump when arranged with the refrigerant gas circuit of such a cooling system.

The general operation of the above example may be described by way of the following example: when the heating apparatus 2 of the present invention is operatively connected to a cooling system in a commercial food processing plant, water is supplied via inlet 17 to fill chamber 10 with unheated water. The plant's cooling system operates to cool the room via and assembly of chillers to a temperature of 3 degrees Celsius. The resulting heated refrigerant gas in the refrigerant gas circuit of the cooling system may be arranged so as to be passed through the immersion coils 1 of the heating apparatus 2. As the water in the chamber 10 absorbs thermal energy from the refrigerant gas, the temperature and pressure of the water within the chamber 10 increases. As the temperature of the water increases, and the heated water begins to rise to the upper region 12 of the chamber 10, the water expands and is forced inward and is pushed downwards towards the lower region 13 of the chamber 10 by way of the internally arranged thermosyphons 34. The water is driven through the thermosyphons 34 at an increasing rate influenced in part by the temperature and pressure of the water in the chamber 10 (the heating apparatus 2 may be configured to endure different operating temperatures and/or pressures based on each particular application).

duwm A0118742661v2 120179441 Once the water has been passed down through the thermosyphons 34, the water enters the lower region 13 of the chamber 10 where it mixes with the cooler water residing at the lower region of the chamber 10 and attempts to reach thermal stability. A thermal convection circuit is therefore established which causes the general body of water to continually circulate (rise upwardly within the chamber 10 and back down into the thermosyphons 34) between the upper 12 and lower 13 regions of the chamber 10 driven, at least in part, by the water seeking to achieve thermal equilibrium. Accordingly, the temperature and pressure differential of the water between the upper 12 and lower 13 regions promotes a circulatory flow of water which continues to circulate without the need for any independent pumping assistance. As a result of this behaviour, the water in the chamber 10 has been found to heat much faster than conventional systems.

As the water throughout the chamber 10 is being heated by the circulating flow, the temperature differential within the chamber 10 begins to reduce as the water in the chamber 10 begins to reach thermal equilibrium. With water removed from the system by way of the outlets 48, additional (cooler) water is introduced into the chamber 10 via fluid supply means 15. This introduction of cooler fluid to the lower region 13 of the chamber 10 results in a temperature differential between the upper 12 and lower 13 regions of the chamber 10 being re-established thereby re-energising the convection circulation effect, which in turn, causes the newly admitted water to heat at an increased rate given that the newly admitted water is surrounded by water that has already been heated.

The number of immersion coils 14 required is generally influenced by the capacity of the heat source 30, or cooling system, to be associated with the arrangement of the heating apparatus 2 used. In the case of a cooling system, such as that of a large commercial supermarket for example, the cooling system may be of sufficient size to warrant up to five immersion coils 14 (in some instances, up to two or three sets of four or five immersion coils 14) located on respective mounting plates 28a, 28b (as shown in Figures 2 and 3) - by way of a

duwm A0118742661v2 120179441 brief example, and although yet to be confirmed, an assembly of four immersion coils is thought to equate to between 800-1,000 k , and an assembly of five immersion coils is thought to equate to around 1,500 kW. In such applications, the chamber 10 may have a fluid capacity of approximately 1,000 litres. In contrast, if the cooling system is, for example, a small gourmet food shop or similar, then the amount of heat generated by the cooling system will be smaller and only two immersion coils 14 on each mounting plate 28a, 28b may be all that is required. In such instances, the heat recovered from the refrigerant gas is thought to be sufficient to work with an embodiment of the heating apparatus 2 having a generally smaller capacity chamber than what might be required for a larger scale application. If the size of the cool room changes, and the capacity of the cooling system is subsequently varied, the number of immersion coils 14 on each mounting plate 28a, 28b can be adjusted to accommodate the change in waste heat generated by the cooling system. For instance, the embodiment of the heating apparatus 2 shown in Figures 1 to 3 relates to a 1,000 litre capacity tank which is generally considered to be suitable for large scale industrial and commercial applications. A smaller chamber with fewer immersion coils 14 may be suitable for single residences following similar principles.

When the heating apparatus 2 is used in connection with a cooling system in a commercial food processing plant or similar application, the fluid contained in the chamber 10 is usually water or some other type of liquid solution, for example a chemical wash, recycled water, etc. Because the immersion coils 14 are immersed in the liquid contained in the chamber 10, the refrigerant gas flowing through the immersion coils 14 is able to transfer thermal energy to the liquid more efficiently. The re-cooling of the heated refrigerant gas in the cooling system is therefore more efficient than that achieved by the conventional re-cooling method of blowing cool air across the tubes containing the refrigerant gas.

Accordingly, the compressors in the cooling system are able to operate more efficiendy as less energy is required to re-cool the refrigerant gas. In this regard, the inventor considers that it is potentially possible that energy savings of up to approximately 60% could be realised by using a suitable arrangement in duwm A011874266lv2 120179441 accordance with the present invention together with a refrigeration cooling system, as compared with traditional applications.

Where no waste heat source is readily available, one can be created by installing a cooling system rather than using dedicated compressor units to heat the gas required and "wasting" the cool air produced. For example, in a domestic application, a cool room could be readily arranged in conjunction with an embodiment of the heating apparatus in accordance with the present invention.

The various ring main fluid circuits 40, 44 (and integrated reticulation systems connected thereto) provide the opportunity in domestic applications for hydronic heating to be installed in conjunction with the provision of a domestic hot water supply. When applied in a high rise building such as an office, hospital or residential tower, a series of heating apparatus 2 could be installed at regular intervals (say every 4 floors) to provide a highly efficient local hydronic heating and hot water system rather than supplying the building from the less efficient conventional plant room arrangement typically at basement, mid and roof levels.

The inventors have tested one prototype embodiment of the present invention for use as a water heating apparatus in a hydronic heating circuit for a domestic residence. The following operational characteristics are therefore presented and described in the context of the core aspects of the present invention having been configured for supplying heated water for domestic application.

The following configuration was employed in the prototype model:

(i) a tank (6) having a chamber (10) was provided by way of a 4mm thick stainless steel 1,000 litre water cylinder; (ii) the chamber (10) included spun domed top and bottom ends so as to assist, at least in part, the tank (6) to withstand the high internal pressures;

duwmA0118742661v2 120Ϊ79441 (iii) within the chamber (10) were four thermosyphon units (34) arranged equidistant from each other near the chamber wall;

(iv) four immersion coils (14) were arranged in the upper region (12) heating assembly (8), and four immersions coils (14) were arranged in the lower region (13) heating assembly (9). Each heating assembly was arranged to be driven by a respective heat pump. This particular arrangement was generally considered appropriate for use with a domestic residence;

(v) a single sacrificial anode (118) was placed at the central

region of the chamber (10);

(vi) three standard electrical elements (3x4.8 kW) (106) were

placed at or near the central region of the chamber (10);

(vii) the chamber (10) included three pressure reduction or relief valves (110);

(viii) within the chamber (10) was a single cold water feed circuit (15) (comprising conduit (94)) entering the chamber from the top and discharging to the lower region (13) of the chamber;

(ix) a sump drain arrangement (120) was provided at the centre of the domed lower end of the chamber (10) having a sump plug (145) and a tap (130) for drainage purposes.

The following table (Table A) of data describes the performance of the unit for heating ambient water held in the chamber over a 2½ hour time period (from cold start-up).

du m AO 118742661 v2 120179441 Table

ΔΤ (mins) Upper (°C) Lower (°C)

S S 21tt ae g a g e 0 17.6 12.7

10 22.6 16.6

20 27.4 20.2

30 32.7 24.2

40 37.5 28

50 42.7 32

60 47.5 35.8

70 52.3 39.5

80 57.1 43.5

90 60.9 46.8

2.9 kW - Upper heat pump (compressor) discontinued

100 64 50.5

110 67 54.1

120 70.3 57.7

3.6 kW - Lower heat pump (compressor) discontinued

Turned REC (recirculating) pump and activiate primary ring circuit

140 75.1 48.5

3.6 kW - Lower heat pump activated

150 77.1 57.6

Discontinued 3x4.8 kW elements

The total power used from cold start-up over the period monitored was calculated to be in the order of 21 kW.

During stage 1, the water within the chamber is heated from ambient temperature using both the upper (8) and lower (9) heating assemblies.

Once the water reached a predetermined threshold temperature (a threshold level generally between around 50-60°C), the upper heating assembly was turned off, allowing only the lower heating assembly to continue heating the water. The heating continues until a further threshold temperature is reached (approximately 58°C), following which the lower heating assembly was also turned off.

duwm A011874266lv2 120179441 For the present example, with the water heated to around 58°C, the internal pressure of the chamber was determined to be in the order of 600 kPa. In further operating configurations, the pressure in the chamber reached around 850 kPa. Once the unit heated the water to this limit (» 58°C), a recirculating (or

REC) pump was activated and a primary ring main circuit was enabled and water was allowed to flow therethrough (so that it may be accessed via one or more of the outlets provided in fluid communication with the ring main circuit). REC pumps are generally not required for hot water circuits but are often required for hydronic heating circuits. Furthermore, REC pumps would normally be required for applications where height might present performance issues such as in the case of multi-level buildings.

It will be appreciated that the delivery of hot water via the outlets will have the effect of lowering the overall effective temperature of the water in the system. In this instance, a third threshold temperature will be reached (approximately 50°C) which has the effect of activating the lower heating assembly so as to provide an appropriate amount of energy to 'top' the system up. The lower heating assembly will continue operating until the temperature of the water reaches the appropriate level desired. It will be appreciated that the temperature thresholds outlined above are provided by way of example only and can be readily varied depending on many factors which may for example include the specific application to which the heating apparatus is directed and relevant regulatory requirements which may apply. Furthermore, the disabling and enabling of the heat pumps, and the times and temperatures at which these events might occur, can be varied depending on, for example, relevant energy availability and energy consumption requirements. For example, both the upper and lower heating assemblies may heat the water until a temperature threshold of around 58°C is reached, at which time, the upper heating assembly may be discontinued. At this time, the lower heating assembly may either be disabled until a lower temperature threshold is reached, or continue du mA011874266lv2 120179441 operating at, for example, a lower energy consumption level. It will therefore be appreciated that the operating regime used can be readily varied as required.

For the prototype configuration described above, the first 1.5 hours of use (ie. heating the water from ambient) incurred an energy consumption in the order of 21 kW. Once the upper heating assembly was discontinued, further heating using only the lower heating assembly incurred an energy consumption of only 18.1 kW. Therefore, over a 2 hour heating period (from generally ambient temperature), around 39.1 kW of energy consumption was incurred.

It will be noted that the chamber, in many embodiments, will be required to support high internal pressures. It will therefore be understood that, depending on the application to which the present invention is applied, the system can be configured so as to withstand significant internal pressures. Thus, within reason, the more pressure the unit can withstand, the higher the

temperature which can potentially be obtained. The prototype unit was designed so as to withstand internal pressures in the order of 2,000 kPa. Operating pressures are, however, generally well below this upper threshold and are expected to reside around 800-850 kPa for safety considerations.

It will be appreciated that the chamber is provided of suitable and sufficient construction so as to withstand the relatively high internal pressures which result as compared with conventional arrangements. For example, the tank 6 may be constructed from materials which accord with ASTM A2 0-316L. All pipes and conduit sections may be fabricated from materials which accord with ASTM A312- TP316L. Materials which accord to this standard and which are readily available include copper and screw-fitted stainless steel and similar alloys. With regard to construction protocols for use in Australia, for the

embodiment described, the chamber is constructed in accordance with Australian Standard (AS) 1210-1997 (Amendment 3). For safety purposes, the tank 6 is associated with a relief valve of suitable capacity as per AS-1210-1997 Section 8, set at a pressure no higher than the design pressure shown on the name plate.

duwm A011874266lv2 120179441 Having regard to installation, embodiments of the heating apparatus 2 are generally to be installed in accordance with AS 3892-2001, and operated and maintained in accordance with AS 3873-2001. Periodic inspection must be carried out in accordance with AS 3788-2006. Any access into the vessel must be in accordance with the relevant confined space regulations. Non-destructive examination and testing of pressure equipment is to be conducted in accordance AS 4037-1999.

Following from the above, it will be appreciated that all components are preferably fabricated in accordance with relevant regulatory standards as may be appropriate. The word 'comprising' and forms of the word 'comprising' as used in this description and in the claims does not limit the invention claimed to exclude any variants or additions.

Modifications and improvements to the invention will be readily apparent to those skilled in the art. Such modifications and improvements are intended to be within the scope of this invention.

duwmA01187-i2661v2 120179441