Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
APPARATUS FOR ENHANCING FUEL EFFICIENCY OF INTERNAL COMBUSTION ENGINES
Document Type and Number:
WIPO Patent Application WO/2011/132042
Kind Code:
A1
Abstract:
Apparatus is provided for enhancing the performance of an internal combustion engine [1] that is fitted with a turbocharger [2] and charge air cooler [3, 30], especially of a vehicle. The apparatus comprises atomizers [4, 6, 7, 31] connected to a supply of water [9, 40] under pressure and activation means [12] is provided to control a supply of water to the atomisers to spray water onto a heat exchanger forming part of the charge air cooler when said activation means is in an "on" condition. The activation means also has an "off' condition. The apparatus includes a controller [13] for controlling the activation means on the basis of at least one of an ambient temperature sensor [15], a hot turbocharged air sensor [21], a cooled turbocharged air sensor [17], an exhaust gas temperature sensor [22] and an engine temperature sensor [18]. The controller is programmed to select one of at least two different spraying programs when the activation means is in an "on" condition with the selection being made, at least in part, and optionally exclusively, on the basis of the input from at least one temperature sensor and most commonly the ambient air temperature.

Inventors:
LOURENS QUINTIS (ZA)
Application Number:
PCT/IB2011/000656
Publication Date:
October 27, 2011
Filing Date:
March 28, 2011
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
LOURENS QUINTIS (ZA)
International Classes:
F01P9/02; F02B29/04
Foreign References:
JPH06317152A1994-11-15
FR2932853A12009-12-25
Attorney, Agent or Firm:
VON SEIDELS (P.O. Box 440, 7446 Century City, ZA)
Download PDF:
Claims:
CLAIMS:

1. Apparatus for enhancing the performance of an internal combustion engine [1] that is fitted with a turbocharger [2] and charge air cooler [3, 30], the apparatus comprising at least one atomizer [4, 6, 7, 31] connected to a supply of water [9, 40] under pressure and wherein activation means [12] is provided to control a supply of water to the at least one atomiser to spray water onto a heat exchanger [31] forming part of the charge air cooler when said activation means is in an "on" condition in order to cool turbocharged air passing through the charge air cooler, the activation means also having an "off' condition, the apparatus being characterized in that it includes a controller [13] for controlling said activation means wherein the controller has an input from at least one of an ambient temperature sensor [15] for sensing ambient temperature, a hot turbocharged air sensor [21] for sensing the air temperature taken before the turbocharged air enters the charge air cooler, a cooled turbocharged air sensor [17] for sensing the air temperature taken after the turbocharged air leaves the charge air cooler, an exhaust gas temperature sensor [22] and an engine temperature sensor [18] for sensing engine temperature, said controller being programmed to select one of at least two different spraying programs when the activation means is in an "on" condition with the selection being made, at least in part, on the basis of the input from at least one temperature sensor.

2. Apparatus as claimed in claim 1 in which the controller has an input from at least two of an ambient temperature sensor, a hot turbocharged air sensor, a cooled turbocharged air sensor and an engine temperature sensor.

3. Apparatus as claimed in either one of claims 1 or 2 in which the controller is a micro processor.

4. Apparatus as claimed in claim 3 in which the microprocessor is integrated or piggybacked onto an existing engine management unit forming part of a relevant engine assembly.

5. Apparatus as claimed in any one of the preceding claims in which there are multiple different spraying programs selectable by the controller on the basis of ambient temperature or engine temperature or both.

6. Apparatus as claimed in claim 5 in which there are from four to sixteen of programs.

7. Apparatus as claimed in any one of the preceding claims in which the different programs involve different activation temperatures at which spraying is initiated and different de-activation temperatures at which spraying is terminated.

8. Apparatus as claimed in any one of the preceding claims in which the different programs involve the selection of different atomizers to be employed in a particular program.

9. Apparatus as claimed in any one of the preceding claims in which the activation means is activated between "on" and "off" by sensed turbocharged air temperature after it has passed through the charge air cooler.

10. Apparatus as claimed in any one of the preceding claims in which ambient temperature is used to select the program to be carried out.

11. Apparatus as claimed in any one of the preceding claims in which single or multiple atomizers are arranged to spray in a predetermined pattern with respect to the heat exchanger of the charge air cooler with greater delivery to a hot entry region of the charge air cooler than the delivery to the exit region from the charge air cooler.

12. Apparatus as claimed in any one of the preceding claims in which the programs are created to maintain the temperature of the cooled turbocharged air [engine inlet air] below about 80°C.

13. Apparatus as claimed in any one of the preceding claims in which the controller is fitted with wireless communication means [25] whereby one or more conditions of the apparatus of the invention can be transmitted to a control facility and the activation means of the apparatus of the invention can be disabled remotely.

14. A vehicle fitted with apparatus as claimed in any one of claims 1 to 13.

15. A vehicle as claimed in claim 14 in which a dedicated water tank [43] for supplying water for use by the apparatus of the invention is supported on transverse supports [41] extending between parallel longitudinally extending chassis members [42] of a load carrying body of the vehicle.

Description:
APPARATUS FOR ENHANCING FUEL EFFICIENCY OF INTERNAL

COMBUSTION ENGINES

FIELD OF THE INVENTION

This invention relates to apparatus for enhancing the fuel efficiency of internal combustion engines that employ a turbocharger of some form or another whereby inlet air to an engine is compressed, at least to some extent. Typically the internal combustion engine would be a diesel engine but the same principles apply equally well to a gasoline or petrol engine.

It is to be understood that the term "turbocharger" is used in a broad sense and includes any device that is used to compress, at least to some extent, inlet air to be fed to an internal combustion engine and would include an engine driven supercharger as well as a conventional turbocharger that is exhaust gas driven.

The term "charge air cooler" will be used to include what is often referred to as an "intercooler" as well as an "after cooler" whilst the term "intercooler" will be used to refer to an "air to air" charge air cooler and the term "after cooler" will be used to refer to an air to water" charge air cooler.

It is to be noted that the invention applies both to the retrofitting of apparatus according to the invention to existing engines as well as to new engines. The engines may be those employed in a vehicle, typically a load carrying transport vehicle including road, rail and waterborne vehicles, or the engine may be of the stationary type such as may be used for generating electricity, pumping water, or moving air. In all instances the application of the invention may influence the design of the charge air cooler of the complete or a partial system. BACKGROUND TO THE INVENTION

It is well known that compressing inlet air to an internal combustion engine, typically by means of a turbocharger, raises the temperature of the air. As a result of the fact that high temperature inlet air would mean inefficient engine operation, and at least partially detract from the purpose of compressing the inlet air in the first instance, charge air coolers are widely installed to cool the compressed air before it enters the internal combustion engine. Such charge air coolers operate effectively only in some instances and under some conditions but do not necessarily provide for efficient operation of the engine under all conditions and, especially, fuel efficiency, and thus do not exhibit a desirable carbon footprint.

Numerous different proposals have been put forward in the literature, especially the patent literature, whereby air leaving a turbocharger can be cooled prior to its being introduced into the relevant engine.

Applicant considers that United States published patent application No US20060185627 describes the most relevant prior art to the present application. That published application describes a simple arrangement in which a driver operated system is provided in a vehicle for manually switching on a water spray that, inter alia, can be directed at a charge air cooler in order to cool the inlet air further and avoid overheating. The arrangement is totally driver operated and therefore subject to abuse or lack of use according to the alertness or otherwise of the driver.

United States published patent application No US20090228192 describes a charge air cooling system for an internal combustion engine in which it is proposed to prevent "knocking" [sometimes referred to as detonation or pinging] of the engine by further cooling air that leaves an intercooler at a temperature at which "knocking" is imminent or actually detected. In this arrangement air is passed through an additional heat exchanger that is cooled by means of air conditioner coolant bled from the air conditioner system of a vehicle. Whilst it is mentioned that the avoidance of "knocking" enhances engine performance and fuel economy, there is no attempt made to improve these aspects beyond what results from the avoidance of "knocking" that is generally regarded as deleterious to an engine.

An integrated air conditioner system is also described in US Patent No US 7,464,748 as well as various other prior art publications.

OBJECT OF THE INVENTION

It is an object of this invention to provide apparatus for enhancing fuel efficiency of an internal combustion engine fitted with charge air compression means typically in the form of a turbocharger. It is another object of the invention to provide apparatus whereby various other features of an internal combustion engine may be improved or enhanced. A paramount object of the invention is to reduce the carbon footprint of an internal combustion engine.

SUMMARY OF THE INVENTION

In accordance with this invention there is provided apparatus for enhancing the performance of an internal combustion engine that is fitted with a turbocharger and charge air cooler, the apparatus comprising at least one atomizer connected to a supply of water under pressure and wherein activation means is provided to control a supply of water to the at least one atomiser to spray water onto a heat exchanger forming part of the charge air cooler when said activation means is in an "on" condition in order to cool turbocharged air passing through the charge air cooler, the activation means also having an "off condition, the apparatus being characterized in that it includes a controller for controlling said activation means wherein the controller has an input from at least one of an ambient temperature sensor for sensing ambient temperature, a hot turbocharged air sensor for sensing the air temperature taken before the turbocharged air enters the charge air cooler, a cooled turbocharged air sensor for sensing the air temperature taken after the turbocharged air leaves the charge air cooler, an exhaust gas temperature sensor and an engine temperature sensor for sensing engine temperature, said controller being programmed to select one of at least two different spraying programs when the activation means is in an "on" condition with the selection being made, at least in part, on the basis of the input from at least one temperature sensor.

Further features of the invention provide for the controller to have an input from at least two of an ambient temperature sensor, a hot turbocharged air sensor, a cooled turbocharged air sensor and an engine temperature sensor; for the controller to be a micro processor optionally integrated or piggybacked onto an existing engine management unit forming part of a relevant engine assembly; for there to be multiple different spraying programs selectable by the controller on the basis of ambient temperature or engine temperature or both, preferably from four to sixteen of such programs; for the different programs to involve different activation temperatures at which spraying is initiated and different de-activation temperatures at which spraying is terminated as well as optionally the selection of different atomizers to be employed in a particular program; for the activation means to be activated between "on" and "off 1 by sensed turbocharged air temperature after it has passed through the charge air cooler [that is the temperature of the engine inlet air about to be drawn into the cylinders]; for ambient temperature to be used to select the program to be carried out; and for the supply of water under pressure to be by way of a suitable pump supplied by one or more dedicated water tanks with activation of the pump constituting said activation means.

Still further features of the invention provide for single or multiple atomizers to be arranged to spray in a predetermined pattern with respect to the heat exchanger of the charge air cooler preferably with greater delivery to the hot entry region of the charge air cooler than the delivery to the exit region from the charge air cooler; for the programs to be created according to engine characteristics and general ambient operating conditions with a particular view to maintaining the temperature of the cooled turbocharged air [engine inlet air] below about 80°C, preferably below about 60°C, especially below about 45°C, and most preferably between about 28°C and 42°C; and for the apparatus to include a flushing spray for flushing the heat exchange surfaces onto which the atomizers spray water.

In the instance of an intercooler, the atomizers may be arranged to spray directly onto the heat exchanger of the intercooler or into a stream of air immediately prior to it contacting the heat exchanger.

In the instance of an after cooler, the atomizers may be arranged to spray directly onto the heat exchanger used to cool coolant water employed in the "air to liquid" charge air cooling process or into a stream of air immediately prior to its contacting the heat exchanger.

Ideally, an air cooled heat exchanger should be introduced between the turbo charger and the intercooler and the atomizers should be mounted in relation to this heat exchanger to effect cooling thereof, in use.

The coolant water used should be of good quality, preferably of a non-scaling nature. The invention is regarded by applicant as being able to perform satisfactorily using pure water but performance has been notably enhanced by the addition of a suitable surfactant, such as SLS (sodium lauryl sulphate) or SDL (sodium dodecyl sulphate), and or sodium tripolyphosphate or other surfactant/descaling agent.

The controller may take many different forms and have many different functions. In particular, the controller may be fitted with wireless communication means whereby one or more conditions of the apparatus of the invention can be transmitted to a control facility and the activation means of the apparatus of the invention can be disabled remotely. Typically this would take place in the form of SMS messages that could be pre-recorded at the appropriate station.

The apparatus could also include a number of other facilities including additional atomizers associated with the charge air cooler that could be manually operated in the event of overheating occurring in spite of the apparatus of the invention.

It is also envisaged that the apparatus could include manually or automatically activated cargo coolant sprays for spraying coolant water onto a cargo, for example of livestock, in extremely hot or dry weather conditions.

It is to be mentioned that, in the instance of a vehicle, a dedicated water tank for supplying water for use by apparatus of the invention needs to be safely and securely attached to the vehicle. For this purpose, it is preferred that a dedicated water tank be supported on transverse supports extending between parallel longitudinally extending chassis members of a load carrying body. The latter may be fixed relative to a driver's cab provided the vehicle's drive chain permits of such location, or may be those of a semi-trailer or a towed trailer.

In order that the invention may be more fully understood different embodiments thereof will now be described with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:-

Figure 1 is a diagram illustrating a basic embodiment of the apparatus of the invention as applied to a diesel engine having a turbocharger and an intercooler as a charge air cooler [that is an "air to air" charge air cooler];

Figure 2 is a schematic elevational diagram illustrating one arrangement of atomizers in association with the intercooler;

Figure 3 is a diagram illustrating a more comprehensive embodiment of apparatus of the invention of the type illustrated in Figure 1 ;

Figure 4 is a schematic elevational diagram illustrating an arrangement of atomizers in association with the intercooler forming part of the apparatus illustrated in Figure 3;

Figure 5 is a diagram illustrating a simple embodiment of the apparatus of the invention as applied to a diesel engine having a turbocharger and an after cooler as a charge air cooler [that is an "air to water" charge air cooler];

Figure 6 illustrates a transport vehicle to show the preferred location of a dedicated water tank;

Figure 7 is a schematic side view of a dedicated water tank; I am and, Figure 8 is a rear view thereof showing the tank supported by two parallel chassis members of the transport vehicle.

DETAILED DESCRIPTION WITH REFERENCE TO THE DRAWINGS

In the embodiment of the invention illustrated in Figure 1 , apparatus for enhancing the performance of an internal combustion engine is fitted to a common rail diesel engine [1] having a turbocharger [2] and a charge air cooler in the form of an intercooler [3] on a transport vehicle.

As shown in Figure 2, there are, in this particular instance, six atomizers arranged in pairs with an inlet pair [4] being located closest to the inlet end [5] of the intercooler; a central pair [6] in the central region thereof; and an outlet pair [7] towards the outlet end [8] of the intercooler. The significance of the different pairs of atomizers will be further described below. The atomizers are all connected to a supply of water that is conveniently contained in a dedicated water tank [9], typically having a suitable capacity generally within the range of 200 to 500 litres. The connection is by way of a suitable pump [10] in order to pressurise the water fed to the atomisers.

Of course, the coolant need not be pure water and the water may include one or more chemicals optionally including a surfactant such as SLS but that, in any event, is selected to enhance cooling and to avoid build-up of deposits on the intercooler when the water vaporizes. A suitable filter [11] is preferably included in the coolant supply line from the pump.

Activation means in the form of a suitable switch [12] controlled by an electronic controller [13] are provided to control the supply of water to the atomisers to activate a water spray onto the intercooler by energizing the pump when the switch is in an "on" condition and de-activate the water spray when the switch is in an "off' condition. It will be understood that water sprayed onto the heat exchanger of the intercooler has the effect of enhancing the cooling of turbocharged air passing through the intercooler consequent predominantly on the absorption of latent heat of vaporization of the water sprayed onto the heat exchange surfaces.

It used to be mentioned that the water may be sprayed directly or indirectly onto the heat exchanger of the intercooler. In tests conducted to date, and in the particular arrangement on the vehicle employed, it was found that it was of advantage to direct the sprays away from the heat exchanger and into a stream of oncoming air that was about to contact the heat exchanger, thereby spraying the water indirectly onto the heat exchanger.

Reverting to the nature of the atomizers, in one example of the apparatus described above, the temperature of the intercooler may range from in the region of 170°C to 200°C at the inlet to the intercooler which is very much above the boiling point of water. The inlet pair [4] and central pair [6] of atomizers were selected to provide a higher rate of atomized water delivery as a result of the fact that the fine droplets of water will immediately become vaporized at the boiling point of the coolant and, in so doing, will absorb latent heat of vaporization. The effectiveness and the efficiency of the system is highly dependent on effectively applying coolant to the section of the charge cooler that is above the boiling point of the coolant.

It is also noted that the dynamics of vaporization of water droplets at the hot surface is of critical importance to the efficiency of the apparatus of the invention and this matter needs to be considered when designing the apparatus. Such dynamics are discussed, for example, in an article by W. Jia, H.-H. Qiu in Experimental Thermal and Fluid Science 27 (2003) 829- 838.

The outlet pair [7] of atomizers, on the other hand, provide for a lower flow rate of water as they will be located opposite the outlet region of the intercooler where the temperature of the intercooler will most likely be below the boiling point of water. Water contacting this region of the heat exchange surface will evaporate according to the temperature of the intercooler, the humidity of the air and the air flow past the heat exchange surfaces. Such evaporation may be expected to take place more slowly.

As indicated above, the apparatus is designed such that the turbocharged air leaving the intercooler [the engine inlet air] would have been cooled to a low temperature of at most 80°C, preferably below about 60°C, especially below about 45°C, and most preferably between approximately 28°C and 42°C. The target temperature of turbocharged air leaving the intercooler, that is to say the temperature of the engine inlet air, and its fluctuation according to prevailing conditions, will be discussed more fully below.

In this embodiment of the invention, the controller has an input from an ambient temperature sensor [15] for sensing ambient temperature, a cooled turbocharged air sensor [16] for sensing the air temperature taken after the turbocharged air leaves the charge air cooler [hereinafter referred to as the inlet air temperature] and typically sensed before the inlet manifold [17], and an engine temperature sensor [18]. As indicated above, it may also have a hot turbocharged air sensor [21] for sensing the air temperature taken before the turbocharged air enters the charge air cooler and an exhaust gas temperature sensor [22], both of which are omitted in this particular instance.

The controller is programmed to select one of multiple different spraying programs when the switch is in an "on" condition with, in this instance, the selection being made exclusively on the basis of ambient temperature. It is to be mentioned, however, that a humidity sensor [not shown] may also provide an input to the controller which could influence the control of at least the outlet pair [7] of atomizers in the event that they are separately controllable, a feature that falls within the scope of this invention but is not a part of this embodiment. The controller is preferably a micro processor that may be self contained or it may be integrated or piggybacked onto an existing engine management unit forming part of the relevant engine assembly.

In earlier tests conducted, five different programs were used according to the ambient temperature sensed as follows:-

Programme Ambient Inlet Air Temp Inlet Air Temp number Temperature Activate De-activate

range Sprays Sprays

1 < 8 °C 34°C 32°C

2 8°C-16°C 35°C 33°C

3 >16°C-26°C 37°C 35°C

4 >27°C-36 °C 41 °C 39°C

5 >37°C 43°C 41 °C

In this instance a simple selection of program was made according to the ambient air temperature and the controller operated to activate the sprays at the stated activation temperature and to de-activate the sprays at the stated de-activation temperature that, on average, were about 2°C below the relevant activation temperature for the relevant program, as shown in the table above.

In later tests, twelve different programs were used according to the ambient temperature sensed as follows:-

Programme Ambient Inlet Air Temp Inlet Air Temp number Temperature Activate De-activate

range Sprays Sprays

1 - 4°C-0°C 34°C 32°C

2 >0°C-4°C 34°C 32°C

3 >4°C-8°C 34°C 32°C

4 >8°C-12°C 35°C 33°C 5 >12°C-16°C 36°C 34°C

6 >16°C-20°C 36°C 34°C

7 > 20°C-24°C 37°C 35°C

8 > 24°C-28°C 38°C 36°C

9 > 28°C-32°C 40°C 38°C

10 > 32°C-36°C 42°C 40°C

1 1 > 36°C-40°C 44°C 42°C

12 > 40°C 44°C 42°C

In still further tests, fourteen different programs were used according to the ambient temperature sensed as follows:-

Programme Ambient Inlet air Temp. Inlet air Temp.

Number Temperature Activate De-activate

Range Sprays Sprays

1 -4°C-0°C 25°C 23°C

2 >0°C-4°C 26°C 24°C

3 >4°C-8°C 27°C 25°C

4 >8°C-12°C 28°C 26°C

5 >12°C-16°C 29°C 27°C

6 >16°C-20°C 30°C 28°C

7 >20°C-24°C 31 °C 29°C

8 >24°C-28°C 32°C 30°C

9 >28°C-32°C 34°C 32°C

10 >32°C-36°C 36°C 34°C

1 1 >36°C-40°C 37°C 35°C

12 >40°C-44°C 39°C 37°C

13 >44°C-48°C 40°C 38°C

14 >48°C-100°C 42 °C 40°C Of course, the programs identified above are only examples that were considered to be suitable to particular vehicles. The programs should be designed according to engine characteristics and general ambient operating conditions with a particular view to maintaining the temperature of the engine inlet air at the levels mentioned above.

The settings of the respective programmes are adjustable in situ, either directly by means of a laptop computer or indirectly by means of a memory "card" that was previously programmed with the aid of a computer such as a personal or laptop computer.

As an alternative to the inlet air temperature being used for control purposes, engine operating temperature may be employed with the target maximum engine temperature, that is an activation engine temperature, of about 95°C, and a deactivation engine temperature about 3°C lower.

The apparatus described above is energized by the motor vehicle battery and electrical system by way of an isolation switch [19].

In use, when the apparatus is energized, the temperature in the inlet manifold is monitored and if it is above the stated activation temperature at a specific ambient temperature the pump is energized and the spray system activated. When the deactivation temperature is reached in the inlet manifold the controller will deactivate the system until such time as the inlet air temperature rises once more to the activation temperature at which stage the cycle will repeat itself.

In tests that have been conducted to date, all atomizers (inlet, central and outlet) were selected to spray droplets of 70 to 90 μ size. The inlet atomizers had a delivery capacity of 13 l/hr and that of the central and outlet atomizers a delivery capacity of 6 l/hr. The pump had the ability to deliver 5.5 bars of pressure at a maximum flow rate of 20 litres per minute. Since this flow rate was never achieved, a pump with a lower volume capacity will probably also suffice. The filter was selected to pass particles having a size of 50 μ or less.

It should be noted that droplet formation, direction and distribution and relative concentration of the spray over the heat exchanger surface should receive suitable attention when designing the orifice size, number, arrangement, placement and control of the atomizers. Also, it is important that water vapour should be allowed to dissipate effectively during the vaporisation phase and that boiling hot spots on the intercooler surfaces should be avoided as it may reduce the effectiveness of the system and also lead to corrosion and erosion problems. It is to be noted that the inclusion of a surfactant has been reported to have the advantage of resulting in a more uniform and smaller droplet size than in the absence of a surfactant.

It is of utmost importance that a sufficient volume of unrestricted and, where required assisted, airflow is permitted through and over the heat exchange surfaces of the charge air cooler during and immediately after the spray cycle. This may be achieved, in the case of a vehicle equipped with an automated engine cooling fan, by the insertion of a relay to activate the fan instantaneously with the commencement of the spraying cycle. The fan operation could be ceased at the end of the spray cycle, or delayed as required. It is to be noted that when a heavy duty truck ascends a steep incline, the speed of the vehicle is reduced to an extent at which an insufficient volume of air to ensure effective cooling is passed over the cooling surfaces of the charge air cooler.

It should also be noted that the operational triggers of an engine cooling fan normally utilize the engine coolant temperature as a reference whereas the aim of this invention is to reduce the temperature of the intake air. The function of an automated speed control system is normally to maintain a constant speed under normal road conditions. Since the cooling of intake air also increases the power output of the internal combustion engine, the ability to maintain a higher speed up a steep incline will be enhanced, thereby completely or partially negating the fuel saving advantages of the system.

This can be overcome by driver instruction furthermore the speed control function may be disarmed. Ideally, the speed control function should be automated to maintain an optimum fuel consumption/work load rating.

The controller may take many different forms and have many different functions. In particular, the controller may be connected to an indicator unit [20] or LED display in the vehicle cab so that a driver may be made aware of certain conditions that may develop. It is envisaged that a green indicator LED will be illuminated when the sprays are functioning properly. On the other hand, a red indicator LED may indicate low water level in the supply to the atomizers, or other malfunction, as the case may be. In the event of an overpressure such as may occur if a blockage is present in one or more of the atomizers, the green LED could simply be extinguished or one of the LED's could be made to flash. An indicator would also be provided to indicate when refilling with water is recommended. It is to be noted that none of these indicators can be extinguished by an operator of a vehicle and can only be restored to normal by remedying the cause.

In keeping with modern electronic practice, the controller is preferably programmed to perform a self analysis each time the ignition of the vehicle is turned on. An alarm may be made to sound if any of the subsystems is nonfunctional.

The relatively basic apparatus described above can be supplemented in many different ways with added features, some of which are illustrated in Figures 3 and 4. The controller may be fitted with, or connected to, wireless communication means [25] whereby one or more conditions of the apparatus of the invention can be transmitted to a remote control facility and whereby the controller of the apparatus can be instructed remotely to disable the apparatus. Typically the communication would take place in the form of SMS messages that could be pre-recorded at the appropriate station.

The apparatus could also include additional atomizers [26] that could be manually operated using a manually operable switch unit [27] in the event of overheating occurring in spite of the apparatus described above. The apparatus may also include a flushing spray [28] for flushing and cleaning the heat exchange surfaces onto which the atomizers spray water. It is also envisaged that the apparatus could include manually or automatically activated cargo coolant sprays [29] for spraying coolant water onto a cargo, for example of livestock, in extreme weather conditions.

Of course, and with reference to Figure 5, the apparatus of the invention may also be associated with an engine having an after cooler [30] that cools the turbocharged air by heat exchange with coolant in a coolant circuit including a heat exchanger [31] for cooling the coolant. In this instance, the atomizers [32] are arranged to spray water directly or indirectly onto the heat exchanger used to cool the coolant employed in the air to liquid charge air cooling process.

Referring now to Figures 6 to 8 of the drawings, the water necessary for operating the apparatus of this invention is usually contained in a dedicated water tank [40] that is safely and securely attached to the vehicle. In one common instance as applied to a truck having a semi trailer, the water tank may be supported on transverse supports [41] extending between parallel longitudinally extending chassis members [42] of the load carrying body at an appropriate position indicated by [43] in Figure 6. The water tank may be shaped especially to be supported on such transverse supports such that an upper portion [44] of each end of the water tank extends over the adjacent support thereby ensuring that the water tank cannot fall from its installed position. Numerous variations may be made to the embodiments of the invention described above without departing from the scope hereof. In particular, it is within the scope of the invention that the controller can activate and deactivate different atomizers, or groups of atomizers independently of each other according to prevailing conditions in which instance suitable control valves would most likely be employed. Considerably more research is necessary in this regard.

The benefits of implementing the apparatus of this invention are many fold. In the first place, a considerable reduction in fuel consumption is to be expected. In the tests conducted as described above a reduction in fuel consumption of in excess of 30% over a 3 month test period was recorded in the instance of one vehicle. Of course, the actual saving in each particular instance would be dependent on, amongst others, the original design parameters of the vehicle, its engine, the road being travelled and the ambient conditions as well as individual driver behaviour.

A concomitant reduction in emissions, notably carbon, will inherently be present in each instance thereby significantly reducing the carbon footprint of the relevant vehicle, an extremely important and topical feature.

Not only this, but, as expected, increased power output from the engine resulted in quicker turnaround times and an accompanying saving in cost.

Still further, cooler engine running conditions and an absence of engine overheating that was previously experienced before the installation of the apparatus of the invention were observed. A reduction in oil consumption was also noted.

The invention therefore provides an extremely useful and effective apparatus for enhancing fuel efficiency and also, it is envisaged, enhancing engine life whilst reducing the carbon footprint of an engine.