EP2180158A1

EP2180158A1 - Arrangement to control coolant flow in an engine

Info

Publication number: EP2180158A1
Application number: EP08167309A
Authority: EP
Inventors: Christopher John Holt; Paul Griffin
Original assignee: Perkins Engines Co Ltd
Current assignee: Perkins Engines Co Ltd
Priority date: 2008-10-22
Filing date: 2008-10-22
Publication date: 2010-04-28

Abstract

An arrangement (10) to control coolant flow in an engine comprising a coolant cavity (14) having a coolant inlet (34) and a coolant outlet 36 for flow of a coolant; an oil cooler matrix (16) positioned in the coolant cavity (14) and having a channel (46a, 46b) for circulation of oil; and at least one baffle (18) arranged in the coolant cavity (14) to direct the flow of the coolant (14) through the coolant cavity. A method of controlling coolant flow in an engine comprising circulating a coolant through a coolant cavity (14), the coolant cavity (14) having an oil cooler matrix (16); and directing flow of the coolant through the coolant cavity (14) by a baffle (18) arranged in the coolant cavity (14).

Description

Technical Field

This disclosure relates generally to engines of vehicles and machines, for instance generators. This disclosure relates particularly to coolant flow in engines of vehicles.

Background

Cooling of an internal combustion engine may be needed due to high temperatures which may be generated in the engine. Some of the heat generated in the combustion engine may be transferred to the walls of the engine. The high temperatures may damage parts of the engine or the materials within the engine.
During operation of an engine, the engine may be kept in operative mode by using a coolant. The coolant may transport the heat away from a heat source in order to prevent overheating of the engine. Some engines may have an oil cooler to cool the engine oil. Heat from the engine oil may be transferred to the coolant for dissipation of heat through a radiator.
An internal combustion engine may include an engine block. An engine block may be machine cast and are usually made from cast iron or, in modern engines, aluminium and magnesium. The engine block may contain cylindrically bored holes to accommodate the pistons of a multi-cylinder combustion engine. The engine block may comprise points of attachments or recesses for the attachment of engine components for instance the cylinder head, crankcase, engine mounts, drive housing, engine ancillaries and the oil cooler. The engine block may also comprise passages for coolants and lubricants and may have a cast pocket to receive the oil cooler.
Generally the size and shape of the points of attachments and recesses within the engine block may not be easily changed, as machining facilities would require extensive modification. Hence, an oil cooler and the cast pocket in the engine block may be produced with assembly clearances to prevent the oil cooler from fouling on the cast pocket during assembly of the engine block. However, the assembly clearance permits an easy flow of coolant away from the oil cooler in an assembled engine and the transfer of heat from the oil cooler to the coolant may not be optimal.
The present disclosure is directed, at least in part, to improving or overcoming one or more aspects of the prior art system.

Brief Summary of the Invention

In a first aspect, the present disclosure describes an arrangement to control a flow in an engine comprising a coolant cavity having a coolant inlet and a coolant outlet for flow of a coolant; an oil cooler matrix positioned in the coolant cavity and having a channel for circulation of oil; and at least one baffle arranged in the coolant cavity to direct the flow of the coolant through the coolant cavity.
In a second aspect, the present disclosure describes a method of controlling coolant flow in an engine comprising circulating a coolant through a coolant cavity, the coolant cavity having an oil cooler matrix; and directing flow of the coolant through the coolant cavity by a baffle arranged in the coolant cavity.
Other features and advantages of the present disclosure will be apparent from the following description of various embodiments, when read together with the accompanying drawings.

Brief Description of the Drawings

The foregoing and other features and advantages of the present disclosure will be more fully understood from the following description of various embodiments, when read together with the accompanying drawings, in which:

Fig. 1 is a schematic representation of an engine block according to the present disclosure;
Fig. 2 is a isometric view of an oil cooler matrix according to the present disclosure;
Fig. 3 is a first embodiment of a baffle according to the present disclosure;
Fig. 4 is a second embodiment of a baffle according to the present disclosure;
Fig. 5 is schematic representation of a first embodiment of a baffle arrangement in the coolant cavity;
Fig. 6 is schematic representation of a second embodiment of a baffle arrangement in the coolant cavity;
Fig. 7 is schematic representation of a third embodiment of a baffle arrangement in the coolant cavity; and
Fig. 8 is schematic representation of a fourth embodiment of a baffle arrangement in the coolant cavity.

Detailed Description

This disclosure generally relates to an arrangement to control coolant flow in an engine.
An arrangement 10 of the present disclosure may comprise a coolant cavity 14, an oil cooler matrix 16 and a baffle 18.
Fig. 1 illustrates an engine block 12. Engine block 12 may be machined cast and may have portions to receive engine components. The engine block 12 may be assembled with the engine components. The assembled engine block 12 may be used to assemble an engine, for instance a vehicle engine. Engine block 12 may have the coolant cavity 14 machined thereon and may include a coolant rail 20 for passage of coolant fluid.
Coolant cavity 14 may be formed, for instance through machine casting, according to predetermined requirements. Coolant cavity 14 may be of a suitable size and shape to accommodate the oil cooler matrix 16. Coolant cavity 14 may be substantially rectangular and may have a longitudinal axis. The coolant cavity 14 may have an opening 22 to receive the oil cooler matrix 16. The periphery of the opening 22 may be a contact portion 24 which may include holes 26 for locating and mounting the oil cooler matrix 16 to the engine block 12.
Opposite the opening 22, the coolant cavity 14 may have a side wall 28. The side wall 28 may have recesses 30 to accommodate protrusions from the oil cooler matrix 16. Circumventing the side wall 28 may be a enclosure wall 32. In an assembled engine block 12 the oil cooler matrix 16 may be spaced from the side wall 28 and the enclosure wall 32. A gap may be formed between the oil cooler matrix 16 and the enclosure wall 32. In an assembled engine, the coolant may flow through the gap.
Coolant rail 20 may be formed, for instance through machine casting, according to predetermined requirements. Coolant rail 20 may be a part of continuous coolant circuit. A portion of the coolant rail 20 may lead from the coolant cavity 14 to a radiator and another portion of the coolant rail 20 may lead from the radiator to the coolant cavity.
In an assembled engine, the coolant rail 20 may carry the coolant to and away from the coolant cavity 14. Coolant may be heated in the coolant cavity and coolant rail 20 may carry the heated coolant to a radiator for dissipation of the heat. Coolant rail 20 may return the cooled coolant to the coolant cavity 14. A pump may be connected to the coolant circuit and may propel the flow of coolant through the coolant rail 20 and coolant cavity 14.
Coolant rail 20 may be connected to the opposite ends of the coolant cavity 14. At an end of the coolant cavity 14 the coolant rail 20 may form a coolant inlet 34 at enclosure wall 32. At an opposite end of the coolant cavity 14 the coolant rail 20 may form a coolant outlet 36 at enclosure wall 32. In an assembled engine coolant may enter the coolant cavity 14 through the coolant inlet 34 flow through the coolant cavity 14 and may exit through the coolant outlet 36.
Coolant inlet 34 and coolant outlet 36 may be formed, for instance through machine casting, according to predetermined requirements. Coolant inlet 34 and coolant outlet 36 may be located along the longitudinal axis of the coolant cavity 14.
Fig. 2 illustrates an oil cooler matrix 16. Oil cooler matrix 16 may be supported on a frame 38. Frame 38 may include a reciprocal contact portion 40 to abut the contact portion 24 at the periphery of opening 22. The reciprocal contact portion 40 may be formed in the same shape and size as the contact portion 24. The reciprocal contact portion 40 may have reciprocal holes 42 that may correspond to holes 26 on the contact portion 24. Frame 38 may include locating fasteners 44. Locating fasteners 44 may assist in placement of frame 38 onto engine block 12. In an assembled engine block 12 the reciprocal contact portion 40 and the contact portion 24 may form a seal to prevent leakage of coolant and oil.
Oil cooler matrix 16 may include internally disposed channels 46a and 46b for flow of engine oil to and from the oil cooler matrix 16. In an assembled engine block 12, channels 46a and 46b may lead from the oil cooler matrix 16 into the engine block 12.
In an assembled engine, oil may be carried to the oil cooler matrix 16 for dissipation of heat to the coolant in the coolant cavity 14. Channel 46a may carry heated oil into the oil cooler matrix 16 and channel 46b may return the cooled oiled from the oil cooler matrix 16.
Oil cooler matrix 16 may comprise a series of hollow plates 48. Each plate 48 may be substantially rectangular with a linear side edges 50 and rounded terminal edges 52 and may have a thickness of some millimeters, for instance 3 mm. In an assembled engine, block 12 the longitudinal axis of the oil cooler matrix 16 may be aligned with the longitudinal axis of the coolant cavity 14. Terminal edges 52 may face coolant inlet 34 and coolant outlet 36 at enclosure wall 32.
Channels 46a and 46b may connect plates 48. Each plate 48 may be spaced from one another and may communicate be positioned at terminal edges 52. Channel 46a may be positioned at a terminal edge 52 and the channel 46b may be positioned at opposite terminal edge 52. Oil may flow through plates comprised in oil cooler matrix 16 may vary according to requirements. In one embodiment, the number of plates may be between 9 and 13 plates.
In an assembled engine, coolant flow through the coolant cavity 14 may be directed at the oil cooler matrix 16. The coolant may be directed through the oil cooler matrix 16 between plates 48.
In another embodiment, oil cooler matrix 16 may comprise of a solid body internally segmented by plates or channels.
In a further embodiment, oil cooler matrix 16 may comprise of a solid body having clefts or recesses on the body.
Baffle 18 may be positioned in the coolant cavity 14. The baffle 18 may be positioned along the enclosure wall 32 in the cavity. Baffle 18 may be mounted to a position along the enclosure wall 32. In another embodiment the baffle may be mounted to the side wall 28.
In another embodiment baffle 18 may be mounted to the oil cooler matrix 16. Baffle 18 may be mounted to a position along the side edges 50 or the terminal edges 52 of the oil cooler matrix 16.
Baffle 18 may be mounted mechanically for instance by rivets or mechanical coupling. Baffle 18 may be mounted chemically, for instance by adhesives. Baffle 18 may be composed of suitable heat resistant material and may be composed of resilient material for instance, rubber.
In an embodiment, baffle 18 may be flexible. A flexible baffle 18 may facilitate mounting thereof to the coolant cavity 14 or the oil cooler matrix 16. The flexible baffle 18 may be again composed of rubber, or plastic. During assembly of the engine block 12, a flexible baffle 18 may deform and thereby allow an efficient assembly.
In the assembled engine block 12, baffle 18 may be located between the oil cooler matrix 16 and the walls of coolant cavity 14. Baffle 18 may be located between a side edge 50 or a terminal edge 52 of the oil cooler matrix 16 and the enclosure wall 32.
In the assembled engine, baffle 18 may direct the flow of the coolant through the coolant cavity. Baffle 18 may direct the flow of the coolant at the oil cooler matrix 16.
Fig. 3 illustrates a first embodiment of baffle 18. Baffle 18 may comprise an arcuate portion 54 and a base portion 56. Arcuate portion 54 may have a support end 58 and tapered end 60. Support end 58 may connect the arcuate portion 54 to the base portion 56. Width of tapered end 60 may substantially equal to the height of the oil cooler matrix 16.
Baffle 18 may be mounted to the coolant cavity 14 through the base portion 56. Base portion 56 may comprise rivet holes 62 and a mounting plate 64 for mechanical attachment to the coolant cavity 14. In an embodiment base portion 56 may be bonded to the coolant cavity 14.
In an assembled engine block 12, base portion 56 may be mounted to enclosure wall 32 of the coolant cavity 14 and tapered end 60 of arcuate portion 54 may abut the oil cooler matrix 16.
In another embodiment, tapered end 60 of arcuate portion 54 may be mounted to the oil cooler matrix 16, for instance by adhesive or mechanical coupling, and base portion 56 may abut enclosure wall 32.
In an assembled engine, arcuate portion 54 may direct the flow of coolant. Coolant flowing through coolant cavity 14 may impact the arcuate portion 54 and the flow may be diverted towards oil cooler matrix 16.
Fig. 4 illustrates a second embodiment of baffle 18. Baffle 18 may comprise a guide portion 66, a link portion 68 and a base portion 70. Link portion 68 may connect the guide portion 66 to the base portion 70. Width of guide portion 66 may be substantially greater than the width of the link portion 68. Width of guide portion 66 may substantially equal to the height of the oil cooler matrix 16.
Baffle 18 may be mounted to the coolant cavity 14 through the base portion 70. Base portion 70 may be mechanically or chemically attached to the coolant cavity 14.
In an assembled engine block 12, base portion 70 may be mounted to enclosure wall 32 of the coolant cavity 14 and guide portion 66 may abut the oil cooler matrix 16.
In another embodiment, guide portion 66 may be mounted to the oil cooler matrix 16, for instance by adhesive or mechanical coupling, and base portion 70 may abut enclosure wall 32.
Link portion 68 may be supported from enclosure wall 32, for instance a projection from the enclosure wall 32 or from the link portion 68.
In an assembled engine, guide portion 66 may direct the flow of coolant. Coolant flowing through coolant cavity 14 may abut the guide portion 66 and the flow may be diverted towards oil cooler matrix 16.
In a further embodiment, baffle 18 may be a flat panel which may be mounted to the side wall 28, enclosure wall 32 or oil cooler matrix 16. In an assembled engine, the flat panel may direct the flow of coolant. Coolant flowing through coolant cavity 14 may abut the flat panel and the flow may be diverted towards oil cooler matrix 16.
The baffle 18 may be suitably arranged to direct the flow of coolant through the coolant cavity 14 in an assembled engine. In further embodiments, more than one baffle may be provide to direct the flow of coolant through the coolant cavity 14.
Baffles 18 may be suitably provided. Baffles 18 may be positioned to direct the flow of coolant at the oil cooler matrix 16. Baffles 18 may be mounted to the oil cooler matrix 16 or to the coolant cavity 14 as described in the foregoing paragraphs.
Fig. 5 illustrates a first embodiment of a baffle arrangement in an assembled engine. A first baffle 18 and a second baffle 18 may be positioned between side edge 50 of the oil cooler matrix 16 and the enclosure wall 32 of coolant cavity 14. The baffles 18 may be located proximate to the coolant inlet 34. The baffles 18 may be located proximate to a terminal edge 52 facing the coolant inlet 34.
Coolant flowing from the coolant inlet 34 may flow towards the oil cooler matrix 16 and into gaps in the coolant cavity 14 between the oil cooler matrix 16 and the enclosure wall 32.
Baffles 18 located between the oil cooler matrix 16 and the enclosure wall 32 may direct the coolant flow from the gaps to the oil cooler matrix 16. Coolant may be directed by the baffles to flow through the oil cooler matrix 16 comprising a series of plates 48. Coolant may be directed to flow between plates 48.
Fig. 6 illustrates a second embodiment of a baffle arrangement in an assembled engine. A first baffle 18 and a second baffle 18 may be positioned between terminal edge 52 of the oil cooler matrix 16 and the enclosure wall 32 of coolant cavity 14. The baffles 18 may be located proximate to the coolant inlet 34. The baffles 18 may be located between terminal edge 52 and the coolant inlet 34.
Coolant flowing from the coolant inlet 34 may flow towards baffles 18. Baffles 18 may direct the coolant flow at the oil cooler matrix 16. Coolant may be directed by the baffles to flow through the oil cooler matrix 16 comprising a series of plates 48. Coolant may be directed to flow between plates 48.
Fig. 7 illustrates a third embodiment of a baffle arrangement in an assembled engine. A first baffle 18 and a second baffle 18 may be positioned between side edge 50 of the oil cooler matrix 16 and the enclosure wall 32 of coolant cavity 14. The baffles 18 may be located proximate to the coolant inlet 34. The baffles 18 may be located proximate to a terminal edge 52 facing the coolant inlet 34. Baffles 18 may extend along side edges 50 towards the opposite terminal edge 52. The opposite terminal edge 34 may face coolant outlet 36.
Coolant flowing from the coolant inlet 34 may flow towards the oil cooler matrix 16 and into gaps in the coolant cavity 14 between the oil cooler matrix 16 and the enclosure wall 32.
Baffles 18 located between the oil cooler matrix 16 and the enclosure wall 32 direct the coolant flow from the gaps to the oil cooler matrix 16. Coolant may be directed by the baffles to flow through the oil cooler matrix 16 comprising a series of plates 48. Coolant may be directed to flow between plates 48. Coolant flow between the plates 48 may be maintained by the extended baffles 18.
Fig. 8 illustrates a fourth embodiment of a baffle arrangement in an assembled engine. A first baffle 18 and a second baffle 18 may be positioned between side edge 50 of the oil cooler matrix 16 and the enclosure wall 32 of coolant cavity 14. The first and second baffles 18 may be located proximate to the coolant inlet 34. The first and second baffles 18 may be located proximate to a terminal edge 52 facing the coolant inlet 34.
A third and fourth baffles 18a may be positioned between side edge 50 of the oil cooler matrix 16 and the enclosure wall 32 of coolant cavity 14. The third and fourth baffles 18a may be located proximate to the coolant outlet 36. The third and fourth baffles 18a may be located proximate to a terminal edge 52 facing the coolant outlet 36.
Coolant flowing from the coolant inlet 34 may flow towards the oil cooler matrix 16 and into gaps in the coolant cavity 14 between the oil cooler matrix 16 and the enclosure wall 32.
First and second baffles 18 located between the oil cooler matrix 16 and the enclosure wall 32 direct the coolant flow from the gaps to the oil cooler matrix 16. Coolant may be directed by the first and second baffles 18 to flow through the oil cooler matrix 16 comprising a series of plates 48. Coolant may be directed to flow between plates 48.
Coolant may flow through the plates 48 and may flow towards the gaps in the coolant cavity 14 between the oil cooler matrix 16 and the enclosure wall 32. Coolant flow may be diverted by the third and fourth baffles 18a to the oil cooler matrix 16.

Industrial Applicability

This disclosure describes at least one baffle 18 for control of coolant flow through a coolant cavity 14.
Heat transfer from oil in the oil cooler matrix 16 may depend on the flow rate and flow path of the coolant. A greater heat transfer may occur with an increased flow rate at the oil cooler matrix 16. A greater heat transfer may occur with a coolant flowing through the oil cooler matrix 16 between plates 48. Further heat transfer may be achieved with an increased coolant flow rate between the plates 48.
The arrangement of baffle 18 and oil cooler matrix 16 in a coolant cavity may be used in engines of vehicles to achieve increased heat transfer rates for the engine oil to the coolant.
Tests have shown that the volume of coolant flowing between the plates may be increased by baffles. A baseline cooler has shown slow moving flow over much of the surface, with some areas of higher velocity flow near to the edges of the plates. The addition of baffles has shown jets of higher velocity flow extending over much of the plates. Results have been compared indicating a noticeable increase of flow rate. Particularly, a baseline model showed a low flow rate at the entry to the cooler, which reduced gradually along the cooler length. A model with baffles according to the disclosure has shown greatly increased flow at the upstream end of the cooler, which decreases as the flow redistributes and enters the gaps around the cooler.
Additionally, a baseline cooler generally shows fairly uniform Heat Transfer Coefficient (HTC) on plates of the oil cooler matrix over the surfaces of the plates. The HTCs are raised near the front of the cooler and along the edges, as high velocity coolant enters the cooler. The jets of high velocity fluid generated by the baffles create regions with very high HTC values. The jets dissipate as they pass through the cooler, significantly increasing the HTCs over the rear part of the cooler.
The industrial applicability of the baffle arrangement for control of coolant flow through a coolant cavity 14 as described herein will have been readily appreciated from the foregoing discussion.
Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims in any claim are followed by references signs, the reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, neither the reference signs nor their absence have any limiting effect on the technical features as described above or on the scope of any claim elements.
One skilled in the art will realise the disclosure may be embodied in other specific forms without departing from the disclosure or essential characteristics thereof. The foregoing embodiments are therefore to be considered in all respects illustrative rather than limiting of the disclosure described herein. Scope of the invention is thus indicated by the appended claims, rather than the foregoing description, and all changes that come within the meaning and range of equivalence of the claims are therefore intended to be embraced therein.

Claims

An arrangement (10) to control coolant flow in an engine comprising:
a coolant cavity (14) having a coolant inlet (34) and a coolant outlet 36 for flow of a coolant;

an oil cooler matrix (16) positioned in the coolant cavity (14) and having a channel (46a, 46b) for circulation of oil; and
at least one baffle (18) arranged in the coolant cavity (14) to direct the flow of the coolant (14) through the coolant cavity.
The arrangement (10) according to claim 1 wherein the baffles are arranged to direct the flow of the coolant at the oil cooler matrix (16).
The arrangement (10) according to claims 1 or 2 wherein oil cooler matrix (16) comprises a series of plates (48).
The arrangement (10) according to claim 3 wherein the baffles are arranged to direct the flow of the coolant through the plates (48).
The arrangement (10) according to any of the preceding claims wherein the at least one baffle (18) is mounted to at least one of the oil cooler matrix (16) or the coolant cavity (14).
The arrangement (10) according to claim 5 wherein at least one baffle (18) is mechanically or chemically mounted.
The arrangement (10) according to any of the preceding claims wherein at least a first baffle (18) is located proximate to the coolant inlet (34).
The arrangement (10) according to claim 7 further comprising a second baffle (18) located proximate to the coolant inlet (34).
The arrangement (10) according to claim 8 wherein the first and second baffles (18) are located along opposite side edges (50) of the oil cooler matrix (16).
The arrangement (10) according to claim 9 wherein the first and second baffles (18) extend along the side edges (50) towards the coolant outlet (36).
The arrangement (10) according to claim 9 further comprising a third and a fourth baffle (18a) located along the side edges (50) of the oil cooler matrix (16) spaced from the first and the second baffles (18) and proximate to the coolant outlet (36).
The arrangement (10) according to any of the preceding claims wherein the baffle is flexible.
The arrangement (10) according to claim 12 wherein the baffle is composed of rubber or plastic.
A vehicle comprising the arrangement (10) according to any one of the preceding claims.
A method of controlling coolant flow in an engine comprising:
circulating a coolant through a coolant cavity (14), the coolant cavity (14) having an oil cooler matrix (16); and

directing flow of the coolant through the coolant cavity (14) by at least one baffle (18) arranged in the coolant cavity (14).