GB2562228A

GB2562228A - Heat Retention apparatus and method

Info

Publication number: GB2562228A
Application number: GB1707312.3A
Authority: GB
Inventors: Richard Hutchins William
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2017-05-08
Filing date: 2017-05-08
Publication date: 2018-11-14
Anticipated expiration: 2037-05-08
Also published as: GB2562228B; GB201707312D0

Abstract

Apparatus suitable for use with an engine 121, the apparatus comprising (i) a thermal shell 131 at least partially surrounding a portion of the engine with a gap to allow air flow in between; and (ii) a chimney portion 144 with two air inlets 144A, 144B and an air outlet 144C located higher than the air inlets, wherein the second inlet 144B receives air from within the thermal shell, i.e. from the air gap. Preferably the engine is a vehicle engine and the first inlet 144A is coupled to the vehicles radiator pack, whereby the radiator fan 143 drives part of the air stream directly into the chimney; another part may be directed via a deflector 147 into the thermal shell structure to cool the covered portion of the engine. A valve 144V is preferably provided at the second inlet, being open to facilitate discharge of hot air from the shell to prevent overheating and being closed when engine heat needs to be retained, e.g. in order to facilitate cold start of the engine. The heat insulating shell 131 may be arranged around an engine block, a separate such shell 160 covering an exhaust system 122 and/or a turbocharger 123.

Description

HEAT RETENTION APPARATUS AND METHOD

FIELD OF THE INVENTION

Aspects of the present invention relate to improvements in the efficiency of vehicle operation. In particular, aspects of the present invention relate to an apparatus for promoting engine heat retention when the engine is not in use, to an engine, to a motor vehicle and to a method.

BACKGROUND

The efficiency of internal combustion engines is known to be dependent at least in part on the viscosity (and therefore the temperature) of the oil used to lubricate the cylinders of the engine. Accordingly, it is desirable for internal combustion engines to be able to attain their normal operating temperature as quickly as possible following a cold start.

It is known to provide a layer of thermal insulation over portions of an engine in order to reduce heat loss when the vehicle is parked for extended periods. However, it is desirable to further reduce heat loss whilst a vehicle is parked whilst still obtaining effective engine cooling during vehicle operations.

It is against this background that the present invention has been conceived. Embodiments of the invention provide a structure, a method or a vehicle which addresses the above problems. Other aims and advantages of the invention will become apparent from the following description, claims and drawings.

SUMMARY OF THE INVENTION

In one aspect of the invention for which protection is sought there is provided apparatus for use with an engine, the apparatus comprising: a shell structure configured to at least partially surround at least a first portion of the engine, the shell structure configured to provide thermal insulation of the at least a first portion of the engine to retain engine heat, the shell structure configured to be provided in a spaced apart relationship with the at least a portion of the engine to allow air flow between the shell structure and the at least a portion of the engine; and a chimney portion, the chimney portion having a first air inlet, a second air inlet and a first air outlet, the first air outlet being higher than the first and second air inlets, the chimney portion being configured to be provided with the second air inlet in fluid communication with air within the shell structure wherein air may flow from the shell structure into the chimney portion through the second air inlet.

Embodiments of the present invention have the feature that a flow rate of air over the engine within the shell structure may be enhanced due to the presence of an air outlet enabling air to flow out from within the shell structure and into the chimney portion through the second air inlet thereof. Furthermore, the flow rate of air through the chimney may be enhanced, in some embodiments, by the introduction of heated air into the chimney. The warm air from within the shell structure may rise within the chimney due to its buoyancy and increase the flow rate of air through the first air inlet of the chimney. The increased flow rate of air through the first air inlet may be exploited to enhance cooling of a portion of the vehicle such as an engine radiator.

Optionally, wherein the first air inlet of the chimney is provided in fluid communication with a blower, wherein at least some air driven by the blower is directed into the chimney.

Optionally, the first air inlet of the chimney is coupled to a radiator pack of the vehicle, the radiator pack comprising a radiator and a blower.

This feature has the advantage that a rate of flow of air over the radiator may be enhanced by the increase in flow rate of air through the chimney as warm air enters the chimney from within the shell structure via the second air inlet.

Optionally, the at least some air driven by the blower is directed to flow within the shell structure between the shell structure and the at least a portion of the engine.

The air may be directed to flow within the shell structure by means of an air velocity deflector.

The apparatus may comprise a valve configured in an open condition to allow air to flow from the shell structure through the second air inlet and in a closed condition to prevent air flow through the second air inlet.

This feature has the advantage that the rate of air flow out from within the shell structure may be controlled in dependence on the state of the valve. It is to be understood that, in the open condition, the valve allows increased cooling of the engine and may allow an increased air flow rate through the chimney. In the closed condition the valve may enable the shell structure to trap air warmed by the engine within the shell structure, reducing the rate of cooling of the engine.

Optionally, the valve is configured automatically to open when a sufficient flow rate of air is generated by the blower.

Optionally, the at least a first portion of the engine comprises at least a portion of a block of the engine, the shell structure being configured to at least partially surround the block.

Optionally, the at least a first portion does not include an exhaust manifold; a turbocharger or a supercharger; or an exhaust system component.

Optionally the apparatus may further comprise a second shell structure configured to at least partially surround at least a second portion of the engine, the second shell structure configured to provide thermal insulation of the at least a second portion of the engine to retain engine heat, the second shell structure configured to be provided in a spaced apart relationship with the at least a portion of the engine to allow air flow between the second shell structure and the at least a portion of the engine, the at least a portion of the engine comprising at least one selected from amongst an exhaust manifold; a turbocharger or a supercharger; or an exhaust system component and not comprising a block of the engine.

Optionally, the at least a first portion of the engine includes at least one of: an exhaust manifold; a turbocharger or a supercharger; or an exhaust system component.

Optionally, the at least a first portion of the engine does not include a block of the engine.

The apparatus may further comprise a second shell structure configured to at least partially surround at least a second portion of the engine, the second shell structure configured to provide thermal insulation of the at least a second portion of the engine to retain engine heat, the second shell structure configured to be provided in a spaced apart relationship with the at least a second portion of the engine to allow air flow between the second shell structure and the at least a portion of the engine, the at least a second portion of the engine comprising a block of the engine and not comprising: an exhaust manifold; a turbocharger or a supercharger; or an exhaust system component.

In a further aspect of the invention for which protection is sought there is provided a motor vehicle engine provided with apparatus according to another aspect.

In an aspect of the invention for which protection is sought there is provided a motor vehicle comprising an engine and apparatus according to another aspect.

In one aspect of the invention for which protection is sought there is provided a method for use with an engine comprising: a shell structure configured to at least partially surround at least a first portion of the engine, the shell structure configured to provide thermal insulation of the at least a first portion of the engine to retain engine heat, the shell structure configured to be provided in a spaced apart relationship with the at least a portion of the engine to allow air flow between the shell structure and the at least a portion of the engine; and a chimney portion, the chimney portion having a first air inlet, a second air inlet and a first air outlet, the first air outlet being higher than the first and second air inlets, the chimney portion being configured to be provided with the second air inlet in fluid communication with air within the shell structure wherein air may flow from the shell structure into the chimney portion through the second air inlet.

Optionally, the method may comprise causing a flow of air into the shell structure, wherein air flowing into the structure displaces heated air within the structure.

The method may comprise retaining heated air within the shell structure when the flow of air into the structure ceases.

Some embodiments of the present invention have the feature that air surrounding the engine within the structures that becomes heated by the engine will remain trapped within the structures unless air is forced upwardly into the structures due to movement of the vehicle or the action of a fan device, as discussed below. However, advantageously, when the engine is switched off and air is no longer being forced upwardly into the structures due to movement of the vehicle, ambient air heated by the engine remains substantially trapped within the volumes defined by the structures. It is to be understood that this is due to the greater buoyancy of air warmed by the engine relative to ambient air. Thus embodiments of the present invention have the advantage that circulation of relatively cool, ambient air may take place over the engine block when the engine is in use. Whilst when the engine is switched off, relatively warm ambient air may be trapped between the engine and structures, reducing the rate of cooling of the engine. It is to be understood that, by reducing the rate of cooling of the engine, higher engine start-up temperatures may be enjoyed, depending on the time for which the engine remains switched off. Higher engine startup temperatures reduce losses associated with higher oil viscosity. Higher engine temperatures at start-up may also increase the rate at which an engine after-treatment system warms to its normal operating temperature

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: FIGURE 1 is a schematic illustration of a vehicle having an engine with apparatus according to an embodiment of the invention in cross-sectional side view; FIGURE 2 is a further schematic illustration of the vehicle engine with apparatus of the embodiment of FIG. 1 in perspective view showing an airflow path through the structure; FIGURE 3 is a schematic rear view of the engine with apparatus of the embodiment of FIG. 1; FIGURE 4 is a schematic illustration of a vehicle having an engine and apparatus according to a further embodiment of the invention in cross-sectional side view; and FIGURE 5 is a further schematic illustration of the vehicle engine with apparatus of the embodiment of FIG. 3 in perspective view showing an airflow path through the structure.

DETAILED DESCRIPTION FIG. 1 is a schematic illustration of a front portion of a vehicle 100 according to an embodiment of the present invention in cross-sectional form as viewed in a transverse direction, i.e. with the vehicle viewed from one side (in the present illustration, a right side).

The vehicle 100 has an engine compartment 120 covered by a bonnet (or hood) 103 and separated from a cabin of the vehicle by a cabin bulkhead 102. The engine compartment 120 houses an engine 121 having a head portion (or ‘head’) 121H, a block portion (or ‘block’) 121B and a sump portion (or ‘sump’) 121S. In the embodiment illustrated in FIG. 1 the engine 121 is located between a pair of front wheels 151 of the vehicle 100. An undertray 145 is provided below the engine 121 and spans at least part of a distance between a front bumper 104 and a cabin bulkhead 102. The tray 145 is discontinuous, allowing for flow of air downwardly out from the engine compartment 120. The engine 121 comprises an exhaust manifold 122, a turbocharger or a supercharger 123, a catalytic device 124 and a particulate filter 125, such as a diesel particulate filter or a gasoline particulate filter. In the embodiment shown in FIG. 1 the exhaust manifold 122, the turbocharger 123, the catalytic device 124 and the particulate filter 125 are located to one side ofthe engine block 121B and engine head portion 121H.

The engine 121 is provided with an apparatus 130 for promoting engine heat retention. The apparatus 130 comprises a first shell structure 131 and a second shell structure 160. The first and second shell structures 131, 160 may also be referred to as first and second structures, respectively. The first structure 131 is configured to at least partially surround, or encapsulate, a first portion of the engine 121. The first structure 131 is configured to provide thermal insulation of the first portion of the engine 121. The first structure 131 comprises insulating material. The first structure 131 can retain engine heat when the engine is switched off. The first structure 131 is provided in a spaced apart relationship with the engine 121 to allow air flow between the first structure and the engine 121. The first structure 131 has an open lower face. The first structure 131 is substantially in the form of an inverted cup that encloses the head 121H and substantially the entire block 121B of the engine 121. The sump 121S of the engine 121 protrudes below a lower edge of the shell structure 131 in the embodiment shown. In some alternative embodiments the lower edge of the first structure 131 may be substantially at or below a lower level of the sump 121S. In the embodiment of FIG. 1 the first structure 131 may be said to have an upper, or top, portion and a downwardly-directed skirt portion 132 that projects downwardly from the top portion.

The first structure 131 may be provided as a single integral piece (e.g. which can be lifted from the engine) or as a plurality of pieces which fit together to provide the first structure. Examples of suitable materials for the shell structure include cellular foam or matted fibres. The first 131 may comprise layered skins of material or a composite/bonded assembly of materials.

The first structure 131 and the second structure 160 may be provided in addition to any insulation lining a periphery of the engine compartment 120. For example, insulation material may be provided on one or more of: an underside of the bonnet 103; the cabin bulkhead 102; sides of the engine compartment 120. Alternatively, the first structure 131 and the second structure 160 may be provided instead of any insulation lining a periphery of the engine compartment 120. The structures 131, 160 provide thermal insulation at a closer distance to the engine 121 than insulation lining the engine compartment. The structures 131, 160 provide a more effective way of reducing heat loss from the engine 121.

The second structure 160 is configured to at least partially surround a second portion of the engine 121. In the embodiment shown in FIG. 1 the second portion of the engine includes the exhaust manifold 122, the turbocharger/supercharger 123 (or multiple turbochargers or superchargers), the catalytic device 124 and the particulate filter 125. These components of the engine have a very high operating temperature, e.g. 300-400°C, or up to 800°C. There is an advantage to retaining heat in these components of the engine after shut down. The second structure 160 has an open lower face. In the embodiment shown the second portion of the engine is located alongside the first portion of the engine, i.e. on a side of the engine. In other embodiments the second structure 160 may be configured to at least partially surround one or more of: the exhaust manifold 122, the turbocharger/supercharger 123 (or multiple turbochargers or superchargers), the catalytic device 124 and the particulate filter 125.

An example of a suitable construction of the second structure 160 is a twin-walled structure or a layered structure. An example of a suitable material of the second structure 160 is a metal such as stainless steel.

The vehicle 100 has a radiator pack 140 provided within the engine compartment 120 behind a front grille 105 of the vehicle 100. The front grille 105 optionally has active grill shutters 105S that are pivotable between an open condition and a closed condition. In the open condition the active grill shutters 105S permit a flow of ram air into the engine compartment 120 when the vehicle 100 travels in a forward direction. In the closed condition the active grill shutters 105S block a flow of ram air into the engine compartment 120 when the vehicle 100 travels in a forward direction. The active grill shutters 105S are caused to switch between the open and closed conditions by means of an actuator device under the control of a controller 100C in a known manner.

The radiator pack 140 has a fan device (or blower) 143 arranged to draw air through a radiator 141 and front grille 105 when the active grill shutters 105R are open. The fan device 143 blows the air rearwardly towards the first structure 131. In the present embodiment the fan device 143 is electrically powered although in some embodiments the device 143 may be engine driven.

Some of the air blown rearwardly by the fan device 143 is deflected downwardly by the first structure 131. A device is provided to deflect, or to guide, or to scoop, a portion of the air flowing rearwardly through the engine compartment 120. FIG. 1 shows a deflector 147. This may be called an air velocity deflector 147. The air velocity deflector 147 directs the air under the lower edge 133 of the skirt portion of the first structure 131 and upwardly between the engine 121 and first structure 131. Air drawn through the front grille 105 is thus introduced into the first structure 131 and forced in an upward direction between the engine block 121B and the first structure 131. Existing air within the first structure 131 is therefore displaced, being ultimately forced downwardly out from the first structure 131 and exhausted from the engine compartment 120.

The air velocity deflector 147 may be open or closed at the sides. In some alternative embodiments the deflector 147 may be in the form of an open air-deflecting surface arranged to direct air from the front of the vehicle 100 upwardly into the first structure 131. The deflector 147 may be referred to as a scoop in some embodiments. In some embodiments an air velocity deflector 147 may not be provided.

In FIG. 1 air flow lines are shown, illustrating the flow of air passing through the radiator grill 105, the radiator pack 140, the air velocity deflector 147 and within the first structure 131.

It is to be understood that, in the present embodiment, the flow rate of air through the deflector 147 and up within the first structure 131 may be controlled at least in part by means of the active grill shutters 105R of the front grille 105 (open or closed) and the state of the fan device 143 (on or off).

In the present embodiment, controller 100C is provided for controlling the state of the fan device (switching it on or off) and the state of the active grill shutters 105R (causing them to open and close). The controller 100C monitors the temperature of the engine 121 by means of a temperature sensor 101. When the temperature exceeds a first predetermined temperature the controller 100C causes the active grill shutters 105R to open. For example, the first predetermined temperature can be in the range from around 80-90°C. If the temperature exceeds a second predetermined temperature the controller 100C causes the fan device 143 to switch on in addition to maintaining the active grill shutters 105R in the open condition.

It is to be understood that, in use, the engine 121 and first structure 131, which is fixedly coupled to the engine 121, experience movement within the engine bay 120 such as a rocking movement during acceleration and deceleration. Whilst in some embodiments the air velocity deflector 147 could be coupled to the radiator pack 140 to increase the flow of air through the deflector 147, the fact that the engine 121, first structure and air velocity deflector 147 are decoupled from the radiator pack 140 in the present embodiment eliminates problems associated with direct coupling such as wear. In the present embodiment the air velocity deflector 147 is positioned such that a flow of air is maintained therethrough from the radiator pack 140, when the blower device is running, even at the extremes of movement ofthe engine 121 within the engine bay 120 in normal use.

The apparatus 130 also has a chimney 144. The chimney 144 is provided in front of the first structure 131. The chimney 144 has a first air inlet 144A arranged to receive air blown by blower 143 and an air outlet 144C provided above the level of the first air inlet 144A and first structure 131. In addition the chimney 144 has a second air inlet provided in a wall of the chimney 144 between first air inlet 144A and air outlet 144C. The second inlet 144B is arranged to receive air flowing out from the first structure 131 from an uppermost (or almost uppermost) interior region of the first structure, at or near a front edge thereof in the present embodiment. The first structure 131 and chimney 144 are arranged to be provided in fluid communication via a valve 144V provided within a linking conduit 144L. The valve 144V is switchable by the controller 100C between open and closed conditions.

In use, the controller 100C causes the valve 144V to assume the open condition when either (a) the vehicle engine 121 is switched off and the engine temperature is above a predetermined upper threshold temperature, to prevent overheating, or (b) the engine is running and the engine temperature is above a predetermined lower threshold temperature. If the engine 121 is switched off, or running at a temperature below the predetermined lower threshold temperature, the controller 100C causes the valve to assume the closed condition.

When the valve is opening, a flow path is provided for air warmed by the engine to exit the first structure. When the air enters the chimney, it will typically be at a temperature higher than that of the air blown through the chimney 144 by the blower 143. The air entering the chimney 144 through the second air inlet 144B may be more buoyant than the air within the chimney and tend to rise at a faster rate as a consequence. This may result in an increased flow rate of air through the first air inlet 144A, enhancing air flow through the radiator pack 141.

In the embodiment of FIG. 1, engine sump 121S protrudes below the first structure 131 and is exposed to air flowing between the undertray 145 and first structure 131.

In the embodiment shown, the sump 121S is provided with close-coupled thermal insulation thereover in the form of a sprayed-on foam insulation layer. Other forms of thermal insulation may be useful such as sheet-form insulation bonded to the sump by means of an adhesive, or attached thereto by means of mechanical fixing elements such as screws, bolts, clips or the like. In some embodiments thermal insulation is not provided in contact with the sump 121S. FIG. 2 shows just the structures 131, 160 and chimney 144 with other features being omitted for clarity. A deflector or scoop 161 is provided proximate a forward edge 163 of the second structure 160. The deflector 161 may also be called an air velocity deflector or director. Some of the air blown rearwardly by the fan device 143 (FIG. 1) is collected by the deflector 161. The deflector 161 directs the air under the forward lower edge 163 of the second structure 160 and upwardly into the second structure 160. Air drawn through the front grille 105 is thus introduced into the second structure 160 and forced into the second structure 160. Existing air within the second structure 160 is therefore displaced, being ultimately forced downwardly out from the second structure 160 and exhausted from the engine compartment 120. When the vehicle is at rest, and any fan device 143 is switched off, heated air is retained within the second structure 160. This allows the engine components within the second structure 160 to more quickly reach an optimum operating temperature. For example, the catalytic device may require a shorter time to return to an optimum operating temperature.

The air velocity deflector 161 may be open or closed at the sides. The deflector 161 may be in the form of an open air-deflecting surface arranged to direct air from the front of the vehicle 100 upwardly into the second structure 160. In some embodiments the deflector 161 may not be provided.

As may be seen in FIG. 2, the second structure 160 comprises a forward face 165, a rear face 166, a side face 167 and a top face 168. In other embodiments the second structure may have a rounded shape. The forward face 165 and the rear face 166 are inclined at an acute angle to a horizontal reference. The inclined angle of the forward face 165 and the rear face 166 can assist flow of cooling air through the second structure 160. FIG. 3 shows the engine 121, the first structure 131 and the second structure 160 as viewed from behind. Other components such as the front grille 105 and bonnet 103 are omitted for clarity. The first structure 131 is provided on a side and on a top of the engine 121, in addition to the front and the back of the engine (shown in FIG. 1). In this embodiment, the first portion of the engine 121 can be considered as the engine block 121B and the engine head 121H, and the first structure 131 surrounds the engine block 121B and the engine head 121H on a total of three sides of the engine (front, rear, side) in addition to the top. The first structure 131 includes a portion 134 which terminates alongside the head portion 121H of the engine 121. In this embodiment the first structure 131 does not contact the second structure 160 to prevent any damage due to the high surface temperature of the second structure 160 during operation. In another embodiment, the first structure 131 may contact the second structure 160. The first structure 131 may be formed of a heat resistant material in the region where it contacts the second structure 160. FIG. 3 shows a gap between the second structure 160 and the first structure 131. This gap may provide a function of allowing thermal expansion of the second structure 160 and avoiding contact between the first structure 131 and the (much hotter) second structure 160. The size of the gap may be minimised to avoid thermal loss from the exposed engine 121. FIG. 4 is a side view showing apparatus 230 according to a further embodiment of the present invention. Like features of the embodiment of FIG. 4 to those of the embodiment of FIG.’s 1 to 3 are shown with like reference signs incremented by 100. FIG. 4 shows a similar view to FIG. 1 and FIG. 5 shows a similar view to FIG. 2. In the embodiment of FIG. 4 the chimney 244 of the apparatus 230 is arranged in front of the second structure 260 instead of the first 231 (as in the case of the embodiment of FIG. 1). The second air inlet 244B of the chimney is coupled to the second structure 260 at the top of front side 265 of the second structure 260. A valve 244V is provided in a conduit 244L that directs air flowing out from within the second structure 260 to the chimney 244. The valve 244V is caused to open and close in dependence on the state of the engine 221 (running or not running) and temperature of the engine 221 in a similar manner to the embodiment of FIG.’s 1 to 3.

It is to be understood that the predetermined upper threshold temperature of the second embodiment may be the same as or different from the predetermined upper threshold temperature of the first embodiment. Similarly, the predetermined lower threshold temperature of the second embodiment may be the same as or different from the predetermined lower threshold temperature of the first embodiment.

It is to be understood that, in each of the first and second embodiments, the first structure 131, 231 and the second structure 160, 260 can each be optimised for the portion of the engine that it surrounds. The first portion of the engine (e.g. engine block 121B, 221B) is water-cooled and therefore has a lower operating temperature than the second portion of the engine. The first structure 131, 231 can be formed of a material such as a soft material with a high insulating rating while the second structure 160, 260 can be formed of a material which is better suited to high operating temperatures. The second structure 160, 260 provides thermal insulation to the second portion of the engine, but is engineered to survive high operating temperatures. In any of the embodiments, airflow into each of the first structure 131, 231 and the second structure 160, 260 can be independently controlled. For example, the inlet deflector 161, 261 and the shape of the second structure 160, 260 can be configured to provide a higher flow of cooling air during operation compared to inlet deflector 147, 247 and the first structure 131, 231. A fan device may be provided for each of the structures 131, 161 or 231, 261, and each of the fan devices may be independently controlled to provide a flow of cooling air during operation.

In some embodiments, one or more fan devices may be provided for directing air into the first structure 131, 231 substantially directly and not via the radiator pack 140, 240. Additionally, or alternatively, one or more fan devices may be provided for directing air into the second structure 160, 260 substantially directly and not via the radiator pack 140, 240.

In some embodiments, one or more baffles or other wall-like structures may be provided for controlling the direction of flow of air between the engine 221 and the first structure 131, 231.

It is to be understood that a first structure 131, 231 according to an embodiment of the invention may itself have a lower edge 133, 233 that is any suitable depth (distance) below the top of the engine block 121B, 221 such as 50%, 75%, 80, 90%, 100%, 110%, 120% or the height of the engine 121 or any other suitable depth.

It will be understood that the embodiments described above are given by way of example only and are not intended to limit the invention, the scope of which is defined in the appended claims.

Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of the words, for example “comprising” and “comprises”, means “including but not limited to”, and is not intended to (and does not) exclude other moieties, additives, components, integers or steps.

Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith.

Claims

CLAIMS:

1. Apparatus for use with an engine, the apparatus comprising: a shell structure configured to at least partially surround at least a first portion of the engine, the shell structure configured to provide thermal insulation of the at least a first portion of the engine to retain engine heat, the shell structure configured to be provided in a spaced apart relationship with the at least a portion of the engine to allow air flow between the shell structure and the at least a portion of the engine; and a chimney portion, the chimney portion having a first air inlet, a second air inlet and a first air outlet, the first air outlet being higher than the first and second air inlets, the chimney portion being configured to be provided with the second air inlet in fluid communication with air within the shell structure wherein air may flow from the shell structure into the chimney portion through the second air inlet.

2. Apparatus according to claim 1 wherein the first air inlet of the chimney is provided in fluid communication with a blower, wherein at least some air driven by the blower is directed into the chimney.

3. Apparatus according to claim 2 wherein the first air inlet of the chimney is coupled to a radiator pack of the vehicle, the radiator pack comprising a radiator and a blower.

4. Apparatus according to claim 2 or claim 3 wherein the at least some air driven by the blower is directed to flow within the shell structure between the shell structure and the at least a portion of the engine.

5. Apparatus according to any preceding claim comprising a valve configured in an open condition to allow air to flow from the shell structure through the second air inlet and in a closed condition to prevent air flow through the second air inlet.

6. Apparatus according to claim 5 as depending through claim 2 wherein the valve is configured automatically to open when a sufficient flow rate of air is generated by the blower.

7. Apparatus according to any preceding claim wherein the at least a first portion of the engine comprises at least a portion of a block of the engine, the shell structure being configured to at least partially surround the block.

8. Apparatus according to claim 7 wherein the at least a first portion does not include an exhaust manifold; a turbocharger or a supercharger; or an exhaust system component.

9. Apparatus according to claim 8 further comprising a second shell structure configured to at least partially surround at least a second portion of the engine, the second shell structure configured to provide thermal insulation of the at least a second portion of the engine to retain engine heat, the second shell structure configured to be provided in a spaced apart relationship with the at least a portion of the engine to allow air flow between the second shell structure and the at least a portion of the engine, the at least a portion of the engine comprising at least one selected from amongst an exhaust manifold; a turbocharger or a supercharger; or an exhaust system component and not comprising a block of the engine.

10. Apparatus according to any one of claims 1 to 6 wherein the at least a first portion of the engine includes at least one of: an exhaust manifold; a turbocharger or a supercharger; or an exhaust system component.

11. Apparatus according to claim 10 where the at least a first portion of the engine does not include a block of the engine.

12. Apparatus according to claim 11 further comprising a second shell structure configured to at least partially surround at least a second portion of the engine, the second shell structure configured to provide thermal insulation of the at least a second portion of the engine to retain engine heat, the second shell structure configured to be provided in a spaced apart relationship with the at least a second portion of the engine to allow air flow between the second shell structure and the at least a portion of the engine, the at least a second portion of the engine comprising a block of the engine and not comprising: an exhaust manifold; a turbocharger or a supercharger; or an exhaust system component.

13. A motor vehicle engine provided with apparatus according to any one of the preceding claims.

14. A motor vehicle comprising an engine and apparatus according to any one of claims 1 to 12.

15. A method for use with an engine comprising: a shell structure configured to at least partially surround at least a first portion of the engine, the shell structure configured to provide thermal insulation of the at least a first portion of the engine to retain engine heat, the shell structure configured to be provided in a spaced apart relationship with the at least a portion of the engine to allow air flow between the shell structure and the at least a portion of the engine; and a chimney portion, the chimney portion having a first air inlet, a second air inlet and a first air outlet, the first air outlet being higher than the first and second air inlets, the chimney portion being configured to be provided with the second air inlet in fluid communication with air within the shell structure wherein air may flow from the shell structure into the chimney portion through the second air inlet.

16. A method according to claim 15 comprising causing a flow of air into the shell structure, wherein air flowing into the structure displaces heated air within the structure.

17. A method according to claim 16 comprising retaining heated air within the shell structure when the flow of air into the structure ceases.