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Title:
CONTAINERISED ELECTRICAL GENERATOR AND AIR INTAKE APPARATUS THEREFOR
Document Type and Number:
WIPO Patent Application WO/2018/162911
Kind Code:
A1
Abstract:
A containerised electrical generator is described comprising: an International Organization for Standards, ISO, shipping container having disposed therein an engine configured to generate mechanical power, and an electrical generator configured to convert the generated mechanical power into electrical power. The engine comprises a forced induction system, wherein an air intake apparatus of the forced induction system comprises a baffle for attenuating sound waves exiting the air intake apparatus

Inventors:
DARROCH, Jim (Aggreko UK Limited, LomondgateStirling Road, Dumbarton G82 3RG, G82 3RG, GB)
SHRIVE, Christopher (Aggreko UK Limited, LomondgateStirling Road, Dumbarton G82 3RG, G82 3RG, GB)
TELFER, William (Aggreko UK Limited, LomondgateStirling Road, Dumbarton G82 3RG, G82 3RG, GB)
Application Number:
GB2018/050593
Publication Date:
September 13, 2018
Filing Date:
March 08, 2018
Export Citation:
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Assignee:
AGGREKO UK LIMITED (Lomondgate, Stirling Road, Dumbarton G82 3RG, G82 3RG, GB)
International Classes:
F02M35/12; B65D85/68; B65D88/12; F02B63/04; H02K5/24; H02K7/18
Foreign References:
US20030033994A12003-02-20
US5517822A1996-05-21
US2961549A1960-11-22
CN202284492U2012-06-27
Attorney, Agent or Firm:
MARKS & CLERK LLP (Aurora, 120 Bothwell Street, Glasgow G2 7JS, G2 7JS, GB)
Download PDF:
Claims:
CLAIMS:

1. A containerised electrical generator comprising:

an International Organization for Standards, ISO, shipping container having disposed therein an engine configured to generate mechanical power, and an electrical generator configured to convert the generated mechanical power into electrical power, wherein the engine comprises a forced induction system,

and wherein an air intake apparatus of the forced induction system comprises a baffle for attenuating sound waves exiting the air intake apparatus.

2. A containerised electrical generator according to claim 1 , wherein the air intake apparatus is fitted to an external wall of the ISO shipping container.

3. A containerised electrical generator according to claim 2, wherein the air intake apparatus stands proud of the external wall such that at least one external dimension of the containerised generator is greater than a maximum external dimension of the ISO shipping container.

4. A containerised electrical generator according to claim 3, wherein the air intake apparatus stands proud of the external wall by a distance greater than 300 mm.

5. A containerised electrical generator according to any preceding claim, wherein the baffle defines an indirect path for air passing through the air intake apparatus. 6. A containerised electrical generator according to claim 5, wherein at least a part of the indirect path for air passing through the air intake apparatus is outside an internal volume of the ISO shipping container.

7. A containerised electrical generator according to claim 5 or 6, wherein the baffle comprises one or more baffle members extending from an internal wall of the air intake apparatus at least part of a distance to an opposing internal wall of the air intake apparatus,

the air intake apparatus further comprising an air inlet on a first side of the one or more baffle members and an air outlet on an second side of the one or more baffle members opposite the first side.

8. A containerised electrical generator according to claim 7, wherein the internal wall is a base wall of the air intake apparatus, and wherein the one or more baffle members are connected to opposed sidewalls of the air intake apparatus, such that air passing through the air intake apparatus takes an inverted u-shaped path.

9. A containerised electrical generator according to claim 7 or 8, wherein the one or more baffle members each comprise opposed inner and outer walls and an end cap connecting the inner and outer walls.

10. A containerised electrical generator according to claim 9, wherein the end cap is curved or semi-circular in profile.

1 1 . A containerised electrical generator according to claim 9 or 10 when dependent on claim 8, comprising first and second baffle members separated to define a gap therebetween.

12. A containerised electrical generator according to claim 1 1 , wherein the inner walls of the first and second baffle members face each other, each inner wall comprising a plurality of perforations therein.

13. An air intake apparatus for a forced induction system of a containerised electrical generator, the air intake apparatus fitting to the containerised electrical generator comprising an International Organization for Standards, ISO, shipping container having disposed therein an engine configured to generate mechanical power, and an electrical generator configured to convert the generated mechanical power into electrical power,

the air intake apparatus comprising a baffle for attenuating sound waves exiting the air intake apparatus.

14. An air intake apparatus according to claim 13 and configured to be fitted to an external wall of the ISO shipping container.

15. An air intake apparatus according to claim 14, and configured such that, when fitted to the external wall, the air intake apparatus stands proud of the external wall such that at least one external dimension of the containerised generator is greater than a maximum external dimension of the ISO shipping container.

16. An air intake apparatus according to any of claims 13 to 15, wherein the baffle defines an indirect path for air passing through the air intake apparatus.

17. An air intake apparatus according to claim 16, wherein, when the air intake apparatus is fitted to the external wall, at least a part of the indirect path for air passing through the air intake apparatus is outside an internal volume of the ISO shipping container.

18. An air intake apparatus according to claim 16 or 17, wherein the baffle comprises one or more baffle members extending from an internal wall of the air intake apparatus at least part of a distance to an opposing internal wall of the air intake apparatus,

the air intake apparatus further comprising an air inlet on a first side of the one or more baffle members and an air outlet on an second side of the one or more baffle members opposite the first side. 19. An air intake apparatus according to claim 18, wherein the internal wall is a base wall of the air intake apparatus, and wherein the one or more baffle members are connected to opposed sidewalls of the air intake apparatus, such that air passing through the air intake apparatus takes an inverted u-shaped path. 20. An air intake apparatus according to claim 18 or 19, wherein the one or more baffle members each comprise opposed inner and outer walls and an end cap connecting the inner and outer walls.

21 . An air intake apparatus according to claim 20, wherein the end cap is curved or semi-circular in profile.

22. An air intake apparatus according to claim 20 or 21 when dependent on claim

19. comprising first and second baffle members separated to define a gap therebetween.

23. An air intake apparatus according to claim 22, wherein the inner walls of the first and second baffle members face each other, each inner wall comprising a plurality of perforations therein.

Description:
CONTAINERISED ELECTRICAL GENERATOR AND AIR INTAKE APPARATUS THEREFOR

Technical field

5 The invention relates to containerised electrical generators. More specifically, the invention relates to air intakes for a forced induction system of an engine of a containerised generator. In particular embodiments, the invention relates to methods and apparatus for reducing engine running noise in a containerised electrical generator.

10

Background

Typically, containerised generator systems are deployed and operated from containers that meet standardised shipping container requirements (e.g. dimensions, etc.). Those 15 containers may be modified from a standard container in so far as access panels, air inlet panels, or the like may be provided. The standardised shipping container requirements relate to containers that are sometimes referred to as International Organization for Standards (ISO) containers, which have predefined sizes, shipping weight constraints, etc.

20

Containerised generator systems are readily transportable and can be deployed at sites at which supply of electric power to the site from a power distribution network is prohibitive or insufficient for the needs at site. Such generator systems may also be used where there is an absence of power networks, or indeed where a typically-used 25 power network has been disrupted in some manner (e.g. due to acts of nature). In some cases, the site may be used to feed power to an existing network.

Such containerised generator systems may be stand alone, or may be modular insofar as the power output at site can be provided cumulatively from multiple transportable 30 generator systems, e.g. in a power plant arrangement where a single power output is provided. Further, a containerised generator may be formed of apparatus contained in multiple containers that may be coupled or connected together.

There is a continuing need to deploy, including retrieve, such containerised generator 35 systems quickly and effectively so as to reduce deployment time and costs. In order to minimise costs, and/or maximise power output for a given footprint, there is a further desire to package such systems as effectively as possible with such containers for shipping and transportation, while minimising any compromises in relation to package layout and efficiencies.

In addition, such containerised generators typically deploy an internal combustion engine running on a combustible fuel, such as gas or heavy fuel oil (HFO). These engines are run at high revolutions close to their maximum and therefore generate high noise levels. It is desirable to reduce the amount of the noise generated by the engine that is propagated to the external environment.

This background serves only to set a scene to allow a skilled reader to better appreciate the following description. Therefore, none of the above discussion should necessarily be taken as an acknowledgement that that discussion is part of the state of the art or is common general knowledge. One or more aspects/embodiments of the invention may or may not address one or more of the background issues.

Summary According to the invention in an aspect, there is provided a containerised electrical generator comprising: an International Organization for Standards, ISO, shipping container having disposed therein an engine configured to generate mechanical power, and an electrical generator configured to convert the generated mechanical power into electrical power, wherein the engine comprises a forced induction system, and wherein an air intake apparatus of the forced induction system comprises a baffle for attenuating sound waves exiting the air intake apparatus.

Optionally, the air intake apparatus is fitted to an external wall of the ISO shipping container.

Optionally, the air intake apparatus stands proud of the external wall such that at least one external dimension of the containerised generator is greater than a maximum external dimension of the ISO shipping container. Optionally, the air intake apparatus stands proud of the external wall by a distance greater than 300 mm.

Optionally, the baffle defines an indirect path for air passing through the air intake apparatus.

Optionally, at least a part of the indirect path for air passing through the air intake apparatus is outside an internal volume of the ISO shipping container. Optionally, the baffle comprises one or more baffle members extending from an internal wall of the air intake apparatus at least part of a distance to an opposing internal wall of the air intake apparatus, the air intake apparatus further comprising an air inlet on a first side of the one or more baffle members and an air outlet on an second side of the one or more baffle members opposite the first side.

Optionally, the internal wall is a base wall of the air intake apparatus, and wherein the one or more baffle members are connected to opposed sidewalls of the air intake apparatus, such that air passing through the air intake apparatus takes an inverted u- shaped path.

Optionally, the one or more baffle members each comprise opposed inner and outer walls and an end cap connecting the inner and outer walls.

Optionally, the end cap is curved or semi-circular in profile.

Optionally, the containerised generator comprises first and second baffle members separated to define a gap therebetween.

Optionally, the inner walls of the first and second baffle members face each other, each inner wall comprising a plurality of perforations therein.

According to an aspect of the invention, there is provided an air intake apparatus for a forced induction system of a containerised electrical generator, the air intake apparatus fitting to the containerised electrical generator comprising an International Organization for Standards, ISO, shipping container having disposed therein an engine configured to generate mechanical power, and an electrical generator configured to convert the generated mechanical power into electrical power, the air intake apparatus comprising a baffle for attenuating sound waves exiting the air intake apparatus. Optionally, air intake is configured to be fitted to an external wall of the ISO shipping container.

Optionally, the air intake is configured such that, when fitted to the external wall, the air intake apparatus stands proud of the external wall such that at least one external dimension of the containerised generator is greater than a maximum external dimension of the ISO shipping container.

Optionally, the baffle defines an indirect path for air passing through the air intake apparatus.

Optionally, when the air intake apparatus is fitted to the external wall, at least a part of the indirect path for air passing through the air intake apparatus is outside an internal volume of the ISO shipping container. Optionally, the baffle comprises one or more baffle members extending from an internal wall of the air intake apparatus at least part of a distance to an opposing internal wall of the air intake apparatus, the air intake apparatus further comprising an air inlet on a first side of the one or more baffle members and an air outlet on an second side of the one or more baffle members opposite the first side.

Optionally, the internal wall is a base wall of the air intake apparatus, and wherein the one or more baffle members are connected to opposed sidewalls of the air intake apparatus, such that air passing through the air intake apparatus takes an inverted u- shaped path.

Optionally, the one or more baffle members each comprise opposed inner and outer walls and an end cap connecting the inner and outer walls.

Optionally, the end cap is curved or semi-circular in profile. Optionally, the air intake apparatus comprises first and second baffle members separated to define a gap therebetween.

Optionally, the inner walls of the first and second baffle members face each other, each inner wall comprising a plurality of perforations therein.

Brief description of the drawings

Figure 1 a is a perspective view of a containerised generator comprising apparatus contained within two ISO shipping containers;

Figure 1 b is a partial section through a containerised generator;

Figures 2a and 2b are perspective views of an air intake for a forced induction system;

Figure 3 shows an air inlet of an air intake for a forced induction system and partially shows a baffle of the air intake;

Figure 4 is an exploded view of a louvre panel, an outer filter panel, an inner filter panel and a sub-inlet of an air intake for a forced induction system;

Figure 5 is a section through an air intake for a forced induction system;

Figure 6 is a top view photograph of a baffle of an air intake for a forced induction system; and

Figure 7 is a graphical representation of the photograph of Figure 6. Detailed description

Generally, disclosed herein are methods and apparatus for improved noise reduction in relation to engines used within containerised electrical generators. As discussed above, containerised generators are required to fit within the internal dimension constraints of a container, typically a container meeting ISO shipping container requirements. This places significant constraints on the design of apparatus for use in such generators. In addition, the engines used in the containerised generators may include a forced induction system, such as a turbo charger, to increase engine efficiency and output power.

It will be appreciated that herein the term "shipping container" may generally relate to a container that complies with shipping container standards (e.g. dimensions). In some cases, however, those "shipping containers" may be specifically configured for deployment of a generator system, and may comprise additional components, access panels, etc., as will be appreciated.

Forced induction systems typically comprise a turbine configured to drive additional air through an air intake and into a combustion chamber of the engine during the combustion cycle. In containerised generators, the temperature of the air driven through the air intake should be maintained at or below a specific level, for example 50 degrees Celsius, so that the air used in the forced induction system is of a sufficient density to ensure performance of the engine. It is noted that the temperature of the air driven through the air intake may be higher than 50 degrees Celsius but the engine power may be adversely affected. In addition, the use of a forced induction system and the running of the engine of the generator at high revolutions per minute can result in a high noise level outside the container of the containerised generator.

Containerised generator systems that produce electrical power typically comprise a number of system components, such as engine units coupled together with generator units. These containerised systems are configured to convert mechanical energy provided by the engine into electrical energy at the generator, and so provide an electric power output from the system. Such power output may be supplied to a local power network for further distribution, and/or may be used locally at site. The generator systems may be standalone, or may be modular in so far as the power output from each deployed generator system can be provided cumulatively, e.g. effectively as a power plant, which may supply a local power network or the like.

The following described examples relate to new systems and methods that provide exemplary ways to deploy (including retrieve), maintain, operate etc. such containerised generator systems. In the following examples, engine units have been described that use internal combustion to produce mechanical power, and in particular are configured to operate using gas or HFO. HFO is typically considered to be a lower- cost fuel, and therefore has the potential to provide lower-cost power output at site.

However, using fuels such as gas and HFO in an engine unit can be more complex than other fuels. Therefore, to realise the benefits of using such a low-cost fuel, the cumulative cost of deploying, maintaining and operating such systems must not erode any gains made when using HFO. While engine units running HFO have been considered in the examples below, it will be appreciated that aspects of the following description may equally be used with alternative fuels, and indeed alternative engine units. A skilled reader will readily be able to implement those various embodiments accordingly.

Similarly, the following examples describe systems and methods for use with standardised 40-foot (-12 m) ISO shipping containers. Such containers permit greater volume for shipping than, for example, 20-foot (~6 m) containers, and so may be preferably used with HFO engine units providing greater power output for a given foot print. However, it will be appreciated by a skilled reader than aspects of the following description may equally be used with alternatively-sized shipping containers.

The inventors have appreciated that the reduction of noise may be achieved by providing a baffle assembly at the air intake for a forced induction system. The baffle apparatus may define an indirect (commonly u-shaped or serpentine) path for the air in that there is no line of sight between an inlet and an outlet, which in turn places noise shielding elements in the path of any sound waves emanating from the engine and propagating through the air intake. The inventors have also appreciated that an indirect air path through the air intake results in the air driven through the intake being held inside the air intake for longer. Therefore, if the indirect path is within the container where temperatures are relatively high compared to the external environment, the air may be heated and increase the temperature at the air intake to unacceptable levels. Accordingly, apparatus disclosed herein comprise an external air intake apparatus that may be fitted to an external wall of a containerised generator. The external air intake apparatus is configured to stand proud of the external wall when fitted thereto. That is, the external air intake extends outward from the container beyond a maximum dimension (e.g. width) allowed by the ISO shipping container standards. This is counter-intuitive to the skilled person because containerised generators have specific dimensions to permit efficient and convenient shipping thereof. The external air intake apparatus may be configured to be fitted to a containerised generator after shipping and before or during installation at site. Figure 1 a shows a containerised generator 100 comprising apparatus for generating electrical power contained within two ISO containers 102, 104. The lower container 102 includes an engine unit that is configured to generate mechanical energy and an electrical generator unit configured to convert the mechanical energy into electrical power. The upper container 104 includes a number of cooling apparatus for cooling various parts of the containerised generator and, in particular, the engine unit. The upper container 104 also comprises grilles 106a-c (and corresponding grilles on the opposite side of the container 104 - not shown in Figure 1 a) configured to allow air to pass through and be used for cooling in the cooling apparatus.

The upper container 104 also comprises an air intake apparatus 108 for a forced induction system of the engine unit. As can be seen in Figure 1 a, the air intake apparatus 108 is fitted to an exterior wall 1 10 of the upper container 104. In the example of Figure 1 a, the air intake apparatus 108 is generally cuboidal in shape and has an air inlet 1 12 located at a surface of the apparatus 108 that is substantially parallel to the external wall 1 10. The air inlet 1 12 comprises a plurality of louvres and a filter, as explained in greater detail below.

Figure 1 b shows an elevation of an end of the containerised generator 100 of Figure 1 a with a section cut away to show a number of features of the air intake apparatus 108 and the forced induction system.

As can be seen, the air intake apparatus 108 is fitted to the external wall 1 10 of the upper container 104. The air inlet 1 12 has louvres 1 14 fitted to prevent debris being drawn into the forced induction system from above into the air intake apparatus 108 during operation of the forced induction system. Downstream (i.e., closer to the engine unit) of the louvres 1 14, the air inlet 1 12 further comprises a filter system 1 16 configured to prevent debris entering the air intake apparatus 108. The filter system 1 16 comprises a plurality filter panels and, in exemplary arrangements, an outer filter panel 1 18 and an inner filter panel 120.

The air intake apparatus 108 also comprises air outlet ducting 122 that is connectable to an opening in the external wall 1 10 such that there is fluid connection between the air intake apparatus 108 and transit ducting 124. The transit ducting is connected to an engine air intake 126. The air intake apparatus further comprises skids 128 on which the air intake apparatus may be rested on the ground or other surface. The skids 128 comprise apertures configured to receive the tines of a forklift or other lifting apparatus, in particular for lifting the air intake apparatus 108 during fitting to the external wall 1 10.

Figures 2a and 2b show perspective views of an exemplary air intake apparatus 108. The air inlet 1 12 is divided into a plurality of sub-inlets 1 12a-f. Separate louvre panels, outer filter panels and inner filter panels may be configured to fit each sub-inlet 1 12a-f, as shown in Figure 3. Figure 2b shows a side of the air intake apparatus 108 that is opposed to the air inlet 112 and that abuts and/or is fitted to the external wall 1 10 of the container 104. The air outlet ducting 122 can be seen, along with an air outlet 130.

Figure 3 shows a perspective view of an air intake apparatus 108 with louvre panels and filter panels fitted to four of the sub-inlets 1 12c-f, with the remaining sub inlets 1 12a-b left open. Figure 4 schematically shows how the sub-inlet 1 12a, inner filter panel 120a, outer filter panel 1 18a and louvre panel 114a are fitted together, which may be replicated at the other sub-inlets 1 12b-f . The air intake apparatus 108 comprises internal baffles that define an indirect path (e.g. a curved, U-shaped or serpentine path) for air passing through the air intake apparatus 108. Figure 5 shows a section through an exemplary air intake apparatus 108 showing an exemplary baffle arrangement. However, it is noted that other baffle arrangements are possible.

Referring to figure 5, a baffle 132 is positioned within the air intake apparatus 108. The baffle 132 is contained within the outer walls of the air intake apparatus 108. The baffle 132 defines a U-shaped path through the air intake apparatus 108 for air entering through the inlet 1 12 and exiting through the outlet 130. The baffle 132 extends from a base wall 134 of the air intake apparatus 108 part of the distance to an upper wall 136 of the air intake apparatus 108, such that a gap exists between an upper extent of the baffle 132 and the upper wall 136 of the air intake apparatus 108 through which air can travel as it passes through the air intake apparatus 108. In exemplary arrangements, the baffle extends the full width of the air intake apparatus 108 and may be connected to or may abut each of two opposed side walls 137a, 137b (shown in Figures 2a and 2b).

The baffle 132 comprises first and second baffle members 138, 140. The baffle members 138, 140 each extend from the base wall 134 part of the distance to the upper wall 136. In the exemplary arrangement of Figure 5, the baffle members 138, 140 have the same height, although they may have different heights and/or may extend different distances from the base wall 134 towards the upper wall 136. In exemplary air intake apparatus 108, the baffle 132 may extend a distance at least 50% of an internal height of the air intake apparatus 108, at least 60% of an internal height of the air intake apparatus 108 or at least 75% of an internal height of the air intake apparatus 108. The baffle 132 blocks a direct line of sight between the outlet 130 and at least part of (in the example of Figure 5, all of) the air inlet 1 12. The baffle members 138, 140 are spaced across the depth (i.e. a dimension running from the inlet 1 12 towards the container) of the air intake apparatus 108. In exemplary air intake apparatus, the baffle members 138, 140 may be spaced by less than 30% of the internal depth of the air intake apparatus 108, less than 20% of the internal depth of the air intake apparatus 108 or less than 15% of the internal depth of the air intake apparatus 108. In some exemplary air intake apparatus 108, the baffle members 138, 140 may be spaced by less than 300 mm, by less than 250 mm, by less than 200 mm or by less than 100 mm.

Each baffle member 138, 140 comprises an inner plate 138a, 140a, an outer plate 138b, 140b and an end cap 138c, 140c. The end cap 138c, 140c extends between the inner plate 138a, 140a and the outer plate 138b, 140b and in exemplary arrangements is curved or semi-circular such that the top of each baffle member 138, 140 is rounded. In other exemplary arrangements there may be more than two baffle members, each spatially separated across the depth of the air intake apparatus.

In the exemplary air intake apparatus 108 of Figure 5, the inner plate 138a, 140a of one or more of the baffle members 138, 140 comprises a plurality of perforations 138d, 140d. These are shown in Figure 6, which is an image looking down on the baffle members 138, 140 and into the space therebetween. The perforations may be in a range from 4 mm to 10 mm, and in a specific example approximately 6 mm, in diameter and may be arranged in rows such that the perforations extend across the entire width of the inner plate 138a, 140a. The spacing between each perforation in a row may be uniform and in a range from 3 mm to 10 mm and in a specific example approximately 4 mm.

The perforations may begin at a distance from an upper extent of the end cap 138c, 140c in a range from 10 mm to 100 mm and in a specific example approximately 60 mm. Further, the rows of perforations may extend towards the base wall 134 of the air intake apparatus 108 by a distance of greater than 30% of the height of the baffle member 138, 140, greater than 50% of the baffle member 138, 140, greater than 70% of the baffle member 138, 140, greater than 80 % of the baffle member 138, 140 or may extend to the base wall 134.

The perforations in each row may be offset from the adjacent row(s). That is, the centre of each perforation in one row may be laterally offset from the centre of each perforation in adjacent rows. In one example, the perforations in a row may be offset from the perforations in an adjacent row such that the centre of each perforation is aligned with the centre of the spacing between perforations in an adjacent row. It is noted that in other exemplary configurations, the baffle may extend from another wall of the air intake apparatus. For example, the baffle may extend from the upper wall or one of the side walls. In addition, there may exist a plurality of baffles extending from opposed walls and defining a serpentine or S-shaped path for air passing through the air intake apparatus.

In use, the forced induction system of the containerised generator is operated such that air is drawn in through the inlet 1 12. The air follows the path shown by the arrows in Figure 5 and passes upwards and over the top of the baffle 132 before descending on the opposite side of the baffle 132 and passing through the outlet 130, which is located at the bottom of the air intake apparatus 108. The air passing through the air intake apparatus therefore follows an inverted u-shaped (or n-shaped) path. The inverted u- shaped path begins at the air intake 1 12 and ends at the air outlet 130. It is noted that air entering at the top of the air inlet 1 12 will define an L-shaped path to the outlet 130, but there is still no direct, line of sight, path for air between the inlet 1 12 and the outlet 130. Air passing through the outlet 130 is directed into the transit ducting 124 and into the air inlet 126 of the engine.

Noise generated by the engine and/or the forced induction system is restricted from exiting the container 104 via the air intake apparatus 108 by the baffle 132. In addition, placing the air intake apparatus 108 outside the container 104 means that the indirect air path through the air intake apparatus 108 is in a cooler environment and the air driven into the forced induction system is cooler and denser. The skilled person will be able to envisage other embodiments without departing from the scope of the appended claims.