WO2014016554A1

WO2014016554A1 - Coolant separator

Info

Publication number: WO2014016554A1
Application number: PCT/GB2013/051704
Authority: WO
Inventors: Vivian PAGE; Ian NOLAN; Stuart WAGSTAFF; Jean-Yves TILLIER
Original assignee: Perkins Engines Co Ltd
Current assignee: Perkins Engines Co Ltd
Priority date: 2012-07-27
Filing date: 2013-06-27
Publication date: 2014-01-30
Anticipated expiration: 2015-01-27
Also published as: GB201213377D0; GB2504470B; GB2517103B; GB2517103A; GB201420563D0; CN204436567U; GB2504470A

Description

CQQLANT SEPARATOR

Technical Field

[0001] The present disclosure relates to a cooling system for an engine, and more particularly to a separator for separating gas and liquid in a coolant used in the cooling system.

Background

[0002] Coolant flowing in a cooling system for an engine can become aerated. The aerated coolant may cause a reduction in the efficiency of a pump, contributing to an overall reduction in the coolant flow in the cooling system. The reduced coolant flow may in turn result in inadequate cooling of various components present in the system. If unchecked, deterioration in performance of the pump may lead to thermal issues especially in an engine head or other heat exchanger elements present in the system.

[0003] Typically, high performance engines make use of swirl pots to separate air bubbles present in the coolant. Commercial engines use shunt tanks or radiator header tanks to provide an area of low coolant flow for the de-aeration of the coolant. However, these solutions are generally ineffective at separating relatively small air bubbles, which have a tendency to be easily re-entrained into the coolant. Also, these solutions take up considerable space, which may not be available on some machines.

[0004] For example, U.S. Published Application No. 2009/0134175 relates to a fuel tank that is made of a plastic material. The fuel tank includes, but is not limited to, an outer tank and a swirl pot arranged in the interior thereof. The edge of the swirl pot and the opening of the fuel tank are connected positively.

Summary of the Disclosure

[0005] The present disclosure provides a separator for separating gas and liquid in a coolant, the separator comprising a hollow body having a first end and a second end; an inlet arranged towards the first end; a gas outlet; a liquid outlet arranged towards the second end; and a conduit mounted in the hollow body and defining a gas flow path at least partway between the first end and the second end. [0006] Other features and aspects of this disclosure will be apparent from the following description and the accompanying figures.

Brief Description of the Figures

[0007] Figure 1 is a schematic view of a cooling system for an engine, including a separator, according to one embodiment of the present disclosure;

[0008] Figure 2 is a schematic view of another cooling system including the separator;

[0009] Figure 3 is a perspective view of the separator;

[0010] Figure 4 is a cross-sectional view of the separator shown in Figure 3; and

[0011] Figure 5 is another cross- sectional view of the separator shown in Figure 3.

Detailed Description

[0012] Wherever possible, the same reference numbers will be used throughout the figures to refer to the same or like parts. Figures 1 and 2 illustrate exemplary cooling systems 100, 200 respectively for an engine 102 according to various embodiments of the present disclosure. In one embodiment, the engine 102 may include for example, a diesel engine, a gasoline engine, a gaseous fuel powered engine such as a natural gas engine, a combination of known sources of power or any other type of power source apparent to one of skill in the art. Further, as shown in those figures, the engine 102 may include an engine head 104 and an engine block 106.

[0013] A heat exchanger or a radiator 108 may be fluidly connected to the engine 102, in order to dissipate heat from a coolant leaving the engine 102. A person of ordinary skill in the art will appreciate that any suitable coolant known in the art may be used, for example the coolant may include distilled water or a mixture of water, antifreeze and other additives. A first passageway 110 may supply a coolant flow from the engine head 104 to an inlet of the radiator 108. Further, a second passageway 112 may be connected to an outlet of the radiator 108 to permit flow of the coolant away from the radiator 108.

[0014] A thermostat controlled valve 114 may be disposed in the first passageway 110. The thermostat controlled valve 114 may control the coolant flow into the radiator 108. One of ordinary skill in the art will appreciate that the thermostat controlled valve 114 may be configured to re-circulate the coolant flow through a bypass circuit until a temperature of the coolant reaches a pre-determined threshold. On reaching the predetermined threshold, the coolant flow may be routed towards the radiator 108. It should be noted that the placement of the thermostat controlled valve 114 depicted in the accompanying figures illustrates an outlet controlled cooling system. An inlet controlled cooling system, wherein the thermostat controlled valve 114 may be placed within the second passageway 112 also lies within the scope of this disclosure.

[0015] As shown in Figures 1 and 2, a pump 116 may be disposed in the second passageway 112. The pump 116 is fluidly connected to the engine block 106 in order to circulate the coolant within the engine 102. The pump 116 may include a fixed displacement or variable displacement pump known in the art. Further, an expansion tank 118 may be fluidly connected to the radiator 108 via a third passageway 120. The expansion tank 118 may provide volume for the thermal expansion of the coolant. The expansion tank 118 may also serve as a coolant reservoir to ensure the presence of coolant despite evaporative losses over time.

[0016] The coolant flowing in the cooling system 100, 200 may contain gas in the form of air bubbles. In the present disclosure, as shown in Figures 1 and 2, a separator 122 may be provided in the cooling systems 100, 200, for separating the gas and liquid in the coolant. Figures 1 and 2 illustrate different locations in the cooling systems 100, 200 where the separator 122 may be disposed. The separator 122 may include a hollow body 124. The separator 122 may also include an inlet 126, a gas outlet 128 and a liquid outlet 130 to connect the separator 122 to various components in the cooling systems 100, 200. In one embodiment, the separator 122 may be made of metal or any other suitable material. The detailed structure of the separator 122 will be explained in connection with Figure 3.

[0017] Referring to Figure 1, in one embodiment, the separator 122 may be disposed in the first passageway 110, more specifically between the radiator 108 and the thermostat controlled valve 114. It should be noted that in this arrangement, the separator 122 is disposed in series with respect to the radiator 108 of the cooling system 100. As shown, the inlet 126 of the separator 122 may be fluidly connected to the thermostat controlled valve 114. Further, the liquid outlet 130 of the separator 122 may be fluidly connected to the inlet of the radiator 108. In this case, the gas outlet 128 of the separator 122 may be connected to the expansion tank 118 via a communication line 132. [0018] In another embodiment, as shown in Figure 2, the separator 122 may be positioned in parallel with respect to the radiator 108. In this case, the separator 122 may be disposed in the bypass branch 202, more specifically between the thermostat controlled valve 114 and the pump 116. The inlet 126 of the separator 122 may be connected to a fluid junction downstream of the thermostat controlled valve 114 and the liquid outlet 130 of the separator 122 may be connected to a fluid junction upstream of the thermostat controlled valve 114. Further, the gas outlet 128 of the separator 122 may be connected to the expansion tank 118 via the communication line 132. In yet another embodiment, the separator 122 may be disposed in both the first passageway 110 as well as in the bypass branch 202.

[0019] Moreover, it should be understood that parameters related to the separator 122 such as size of the inlet 126, the liquid outlet 130 and the gas outlet 128, length of the hollow body 124, material used, and the like, may vary depending on the application. For example, the separator 122 used in the cooling system 200 may have a relatively shorter hollow body 124 than that used in the cooling system 100. This may be because a smaller portion of the coolant flows through the separator 122 located in the bypass branch 202 as against a full flow arrangement provided in the cooling system 100. A person of ordinary skill in the art will appreciate that the positioning of the separator 122 depicted in the accompanying figures is merely exemplary and may vary without any limitation.

[0020] Figure 3 illustrates an exploded view of the separator 122. The separator 122 may include the hollow body 124 having a first end 302 and a second end 304. The hollow body 124 may be generally cylindrical so as to define a longitudinal axis AA. Further, the inlet 126 of the separator 122 may be arranged towards the first end 302 of the hollow body 124. In one embodiment, the inlet 126 may have a substantially rectangular cross section. The inlet 126 may be configured to receive at least a portion of the coolant flowing through the cooling systems 100, 200. As shown in the accompanying figures, the inlet 126 may be located substantially tangentially to the hollow body 124. Also, the gas outlet 128 may be located towards the first end 302 of the hollow body 124. It should be noted that the gas outlet 128 may alternatively be located towards a rear middle portion of the hollow body 124. In one embodiment, the gas outlet 128 may include an opening 306 provided at the first end 302 of the separator 122. [0021] The gas outlet 128 may be provided substantially coaxially to the hollow body 124, along the longitudinal axis AA. Further, the liquid outlet 130 of the separator 122 may be arranged towards the second end 304 of the hollow body 124. As shown in the accompanying figures, the liquid outlet 130 may be arranged laterally with respect to the longitudinal axis AA of the hollow body 124. In an embodiment, based on the application, the liquid outlet 130 may be arranged substantially axially or parallel to the longitudinal axis AA of the hollow body 124. Moreover, the hollow body 124 may define an hour glass chamber such that there is a reduction in throat diameter partway along the length of the hollow body 124.

[0022] Figures 4 and 5 depict different cross sectional views of the separator 122, according to an embodiment of the present disclosure. As shown, the separator 122 may include a conduit 402 mounted in the hollow body 124. The conduit 402 may define a gas flow path at least partway between the first end 302 and the second end 304 of the hollow body 124. In one embodiment, the conduit 402 may include an outlet end 404 proximal to the gas outlet 128 and an inlet end 406 distal to the gas outlet 128. Moreover, the conduit 402 may have a hollow cylindrical shape or a hollow conical shape. Figures 4 and 5 depict two different variations of mounting the conduit 402 in the hollow body 124.

[0023] Referring to Figure 4, a plurality of ribs 408 extending radially from an inner surface of the hollow body 124 may be used to mount the conduit 402 in the hollow body 124. The plurality of ribs 408 may be provided proximal to the first end 302 of the hollow body 124, such that the conduit 402 extends into the gas outlet 128. Alternatively, as shown in Figure 5, the outlet end 404 of the conduit 402 may be integral with the first end 302 of the hollow body 124. In this arrangement, the conduit 402 may be integral with the gas outlet 128 of the hollow body 124. A person of ordinary skill in the art will appreciate that the variations of mounting the conduit 402 described herein are merely exemplary and do not limit the scope of this disclosure. Moreover, in one embodiment, a plurality of perforations in the form of holes or slots (not shown in figures) may be provided on the conduit 402.

[0024] The present disclosure relates to providing an effective design for the separation of the relatively small air bubbles, having a diameter of approximately 100 microns and above, from the coolant flowing through the separator 122. The conduit 402 is configured to provide the gas flow path for the separated air bubbles to rise under the inf uence of the buoyancy forces and pass out of the separator 122 via the gas outlet 128. A person of ordinary skill in the art will appreciate that the separator 122 may be easily installed into standard cooling systems 100, 200. In some cases, the separator 122 may be used as a replacement for the shunt tank in the system. Industrial Applicability

[0025] The working of the separator 122 will now be described in detail. During operation, at least a portion of the coolant may be received by the inlet 126. Due to the substantially tangential positioning of the inlet 126 with respect to the hollow body 124, the coolant flow may adopt a cyclonic or swirl flow from the first end 302 towards the second end 304 of the hollow body 124. It should be understood that typically, the velocity of the swirl flow of the coolant within the hollow body 124 may be relatively high in the core of the separator 122.

[0026] The conduit 402 mounted within the hollow body 124 may be configured to generate a low velocity region in the core of the separator 122 to facilitate the separation of the gas and liquid in the coolant. It should be noted that the liquid present in the coolant flow is comparatively heavier and may be urged outwardly in the swirl flow. Also, the liquid may fall downwardly towards the second end 304, due to the effect of gravity and the centrifugal force generated within the hollow body 124. Whereas, the gas may be present inwardly of the swirl flow and may collect in the form of air bubbles at the inlet end 406 of the conduit 402. This may result in the separation of the gas and liquid in the coolant. In an embodiment, the separated gas may enter the separator 122 via the plurality of perforations provided along at least a portion of a length of the conduit 402. The air bubbles may then rise within the gas flow path towards the outlet end 404 of the conduit 402 under effect of buoyancy forces.

[0027] Thereafter, the separated gas may exit the separator 122 via the gas outlet 128 which is connected to the conduit 402. The separated gas may then enter the expansion tank 118 via the communication line 132 which extends from the gas outlet 128 of the separator 122. Moreover, the separated liquid may exit the separator 122 via the liquid outlet 130. The separated liquid may enter the radiator 108 in the cooling system 100 or the pump 116 in the cooling system 200.

[0028] One of ordinary skill in the art will appreciate that the conduit 402 may promote better swirling characteristics in a flow field within the separator 122, thereby leading to improved separation efficiency. Moreover, the centrifugal force generated within the separator 122 may be directly proportional to the velocity of the coolant flowing within the separator 122 and inversely proportional to a radius of the hollow body 124. Thus, a rectangular shaped inlet 126, as shown in the accompanying figures, may provide a reduction in flow area of the inlet 126 and thereby cause an increase in the velocity of the coolant flow into the separator 122. Also, the reduction in the throat radius of the hollow body 124 may facilitate higher levels of swirl and therefore provide improved separation efficiency.

[0029] Although the embodiments of this disclosure as described herein may be incorporated without departing from the scope of the following claims, it will be apparent to those skilled in the art that various modifications and variations can be made. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.

Claims

Claims What is claimed is:

1. A separator for separating gas and liquid in a coolant, the separator comprising:

a hollow body having a first end and a second end;

an inlet arranged towards the first end;

a gas outlet;

a liquid outlet arranged towards the second end; and

a conduit mounted in the hollow body and defining a gas flow path at least partway between the first end and the second end.

2. The separator of claim 1, wherein the conduit includes an outlet end proximal to the gas outlet and an inlet end distal to the gas outlet.

3. The separator of claim 1, wherein the inlet is arranged substantially tangentially to the hollow body.

4. The separator of claim 1, wherein the gas outlet is arranged substantially axially to the hollow body.

5. The separator of claim 1 further including ribs for mounting the conduit within the hollow body.

6. The separator of claim 1, wherein the conduit is integral with the first end of the hollow body.

7. The separator of claim 1, wherein the hollow body has a substantially uniform cross section.

8. The separator of claim 1, wherein the hollow body includes a diametrically smaller portion to affect coolant speed.

9. The separator of claim 1, wherein the conduit is configured to generate a low velocity region in coolant flow for the separation of the gas and the liquid in the coolant.

10. The separator of claim 9, wherein the gas flow path directs the separated gas towards the gas outlet of the hollow body.

11. The separator of claim 1, wherein the conduit is configured to have a hollow cylindrical shape or a hollow conical shape.

12. The separator of claim 1, wherein the gas outlet is arranged towards the first end of the hollow body.

13. The separator of claim 1 further including a plurality of holes provided along at least a portion of a length of the conduit.