阅读说明：本技术 曲轴箱通风系统的受热入口 (Heated inlet for crankcase ventilation system ) 是由 L·D·克雷斯 R·A·劳伦斯 W·詹金斯 于 2020-01-23 设计创作，主要内容包括：本发明涉及曲轴箱通风系统的受热入口。一种用于使采用天然气作为燃料源的内燃机的曲轴箱通风的方法可包括通过空气过滤器过滤环境空气。该方法还可包括通过夹套式热交换器加热所过滤的环境空气。该方法可进一步包括将受热的环境空气引导通过曲轴箱的入口以吹扫来自曲轴箱的包括天然气的吹漏气。(The invention relates to a heated inlet of a crankcase ventilation system. A method for ventilating a crankcase of an internal combustion engine that employs natural gas as a fuel source may include filtering ambient air through an air filter. The method may further comprise heating the filtered ambient air by a jacketed heat exchanger. The method may further include directing heated ambient air through an inlet of the crankcase to purge blow-by gases including natural gas from the crankcase.)

1. A method for ventilating a crankcase of an internal combustion engine that employs natural gas as a fuel source, comprising:

filtering ambient air through an air filter;

heating the filtered ambient air by a jacketed heat exchanger; and

heated ambient air is directed through an inlet of the crankcase to purge blow-by gases including natural gas from the crankcase.

2. The method of claim 1 wherein the jacketed heat exchanger is coupled to a cooling system of the engine for receiving coolant from the cooling system to heat the filtered ambient air.

3. The method of claim 2 wherein the jacketed heat exchanger comprises:

a housing for receiving and directing the coolant through the heat exchanger; and

one or more tubes positioned inside the shell to receive and direct the filtered ambient air through the heat exchanger, wherein the coolant flows around the one or more tubes for heating the filtered ambient air.

4. The method of claim 3, wherein the shell includes an inlet coupled to the cooling system at a first location and an outlet coupled to the cooling system at a second location downstream of the first location.

5. The method of claim 4, wherein the coolant flows in a serpentine pattern around the one or more tubes from the inlet to the outlet.

6. The method of claim 5, wherein the inlet is coupled to the cooling system downstream of a pump of the cooling system, and

wherein the outlet is coupled to the cooling system upstream of an outlet of the cooling system.

7. The method of claim 6, wherein heating the filtered ambient air comprises heating the filtered ambient air to a temperature of at least fifty-five degrees Celsius (55 ℃).

8. The method of claim 1, wherein the blow-by gas further comprises at least one of air, fuel, or combustion gas.

9. The method of claim 1, further comprising:

the purged natural gas is discharged through an outlet and exits the engine.

10. A crankcase ventilation system for an internal combustion engine using natural gas as a fuel source, comprising:

an air filter for receiving and filtering ambient air;

a jacketed heat exchanger in fluid communication with and downstream of the air filter, the jacketed heat exchanger comprising:

a housing having an inlet and an outlet downstream of the inlet, the inlet and outlet coupled to a cooling system of the engine for flowing coolant through the housing; and

one or more tubes positioned inside the shell to receive and direct the filtered ambient air through the heat exchanger, wherein the coolant flows around the one or more tubes for heating the filtered ambient air; and

a crankcase of the internal combustion engine having an inlet in fluid communication with the heat exchanger for receiving heated ambient air.

Technical Field

The present disclosure relates generally to crankcases for internal combustion engines, and more particularly to heated inlets for crankcase ventilation systems for such internal combustion engines.

Background

Internal combustion engines typically include a crankcase to provide a housing for a crankshaft of the engine. During operation of the engine, blow-by gases (e.g., gaseous fuel, air, and/or combustion gases) may leak into the crankcase. Blow-by gases can contaminate the oil lubrication system of the engine, can pressurize the crankcase, and can affect overall engine emissions. Further, if the engine employs a gaseous fuel (e.g., natural gas or landfill gas) as the fuel source, the blow-by gases may include corrosive fumes, such as sulfur. The crankcase may include a ventilation system, such as an inlet/outlet ventilation system, to assist in purging blow-by gases from the crankcase using fresh ambient air. When the engine is used in a cold environment, the ambient air used in the ventilation system may be cooled such that condensate (e.g., water) is formed in the crankcase. The condensate may combine with corrosive fumes of natural gas that may form harmful acids in the crankcase.

German laid-open publication DE10323265a1 ("265 publication"), published 12, 16, 2004, describes a ventilation system for a crankcase of an internal combustion engine. The' 265 publication discloses a heat exchanger for heating filtered ambient air to dehumidify the crankcase and prevent water from freezing in the crankcase. The vent line is used to recirculate a mixture of vent gas (filtered and heated ambient air) and blow-by gases after the heated ambient air has passed through the crankcase. An oil bypass separator may be used to separate blow-by gases in the mixture, which are returned to the oil sump of the crankcase via a return line. However, the ventilation system of the' 265 publication may not adequately address components (e.g., sulfur) in the fuel that may form harmful acids in the crankcase. Furthermore, the ventilation system of the' 265 publication may not achieve some efficiency in heating the filtered ambient air.

The systems and methods of the present disclosure may solve or solve one or more of the problems set forth above and/or other problems in the art. However, the scope of the present disclosure is defined by the appended claims, not by the ability to solve any particular problem.

Disclosure of Invention

In one aspect, a method for ventilating a crankcase of an internal combustion engine that employs natural gas as a fuel source may include filtering ambient air through an air filter. The method may further comprise heating the filtered ambient air by a jacketed heat exchanger. The method may further include directing heated ambient air through an inlet of the crankcase to purge blow-by gases including natural gas from the crankcase.

In another aspect, a crankcase ventilation system for an internal combustion engine employing natural gas as a fuel source may include an air filter for receiving and filtering ambient air. The crankcase ventilation system may further include a jacketed heat exchanger in fluid communication with the air filter for heating the filtered ambient air. The crankcase ventilation system may further include a crankcase of the internal combustion engine having an inlet in fluid communication with the heat exchanger for receiving heated ambient air.

In yet another aspect, a crankcase ventilation system for an internal combustion engine employing natural gas as a fuel source may include an air filter for receiving and filtering ambient air. The crankcase ventilation system may also include a jacketed heat exchanger in fluid communication with and downstream of the air filter. The jacketed heat exchanger may include a shell having an inlet and an outlet downstream of the inlet. The inlet and outlet may be coupled to a cooling system of the engine for flowing coolant through the shell of the jacketed heat exchanger. The jacketed heat exchanger may also include one or more tubes located inside the shell for receiving and directing filtered ambient air through the heat exchanger. A coolant may flow around the one or more tubes for heating the filtered ambient air. The crankcase ventilation system may further include a crankcase of the internal combustion engine having an inlet in fluid communication with the heat exchanger for receiving heated ambient air.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various exemplary embodiments and together with the description, serve to explain the principles of the disclosure.

FIG. 1 is a perspective view of an internal combustion engine having an exemplary crankcase ventilation system according to aspects of the present disclosure.

FIG. 2 is a perspective view of a heated inlet of a crankcase ventilation system isolated from the engine of FIG. 1.

FIG. 3 is an exploded perspective view of an exemplary jacketed heat exchanger with a heated inlet isolated from the engine of FIG. 1.

FIG. 4 provides a flow chart depicting an exemplary method for ventilating a crankcase of the internal combustion engine of FIG. 1.

Detailed Description

Both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the features as claimed. As used herein, the terms "comprises," "comprising," "includes," "including," "has," "including," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, relative terms, such as, for example, "about," "substantially," and "approximately," are used to indicate a possible variation of ± 10% of the stated value.

Fig. 1 is a perspective view of an internal combustion engine 10 having an exemplary crankcase ventilation system 20, according to aspects of the present disclosure. The engine 10 may be a stationary engine. As used herein, a "stationary engine" may be an engine having a frame that does not move. The stationary engine may be used to drive non-moving equipment such as pumps, generators, manufacturing or factory equipment. In one embodiment, engine 10 may be used in a landfill application to generate electricity. In this way, engine 10 may utilize gaseous fuel. As used herein, "gaseous fuel" may include fuel supplied to engine 10 in gaseous form. The gaseous fuel may include, for example, natural gas, propane, biogas, landfill gas, associated gas, carbon monoxide, hydrogen, or mixtures thereof. In an exemplary embodiment, the gaseous fuel may be natural gas, such as associated gas. Natural gas is an exemplary gaseous fuel having various purity levels. As used herein, "natural gas" refers to pure and relatively impure forms having various amounts of methane and other constituents. Furthermore, as used herein, "associated gas" is a form of natural gas that includes oil deposits. While the exemplary embodiment relates to a stationary engine, it should be understood that engine 10 may also be used in mobile applications (i.e., non-stationary), and may employ any type of fuel.

As shown in FIG. 1, engine 10 may include a frame 12. The frame 12 may support various components of the engine 10, such as a crankcase 14, an engine block 9, and one or more cylinder heads 16 for one or more cylinders 11 (shown schematically in FIG. 2). The engine 10 may include any number of cylinders 11 arranged in any configuration, such as in-line, radial, "V-shaped," or any configuration known in the art. The frame 12 may further support a fuel system, an air system, a cooling system, a turbocharger, or any other conventional engine component.

Referring to fig. 2, the crankcase 14 may provide a housing for the crankshaft 13. The crankshaft 13 may be connected to a plurality of pistons 15 via connecting rods 17. A piston 15 may be slidably and reciprocally disposed within one or more cylinders 11 (which may be integrated with the crankcase 14 as a single structure) and covered by a cylinder head 16. Each cylinder 11, piston 15, and cylinder head 16 may together form a combustion chamber 19. Engine valves, such as intake valve 21 and exhaust valve 23, may control the flow of gases into and out of combustion chamber 19, and may be timed to move relative to the movement of respective piston 15 during a stroke cycle of engine 10. For example, as piston 15 moves through an intake stroke, intake valve 21 may open to allow air and fuel mixture to be drawn or forced into combustion chamber 19. During the compression and power (combustion) strokes, both the intake valve 21 and the exhaust valve 23 may be closed to minimize gas leakage from the combustion chamber 19. During the exhaust stroke, the exhaust valve 23 may be opened to allow byproducts of combustion to be pushed out of the combustion chamber 19. Thus, as is known in the art, the piston 15 may power the crankshaft 13 to provide useful mechanical work motion to the flywheel 18.

During operation of the engine 10, blow-by gases may leak into the crankcase 14. As used herein, "blow-by" gas may include air, fuel, combustion gases, and/or mixtures thereof between the piston 15 and the cylinder wall of one or more cylinders 11 leaking into the crankcase 14. When gaseous fuel is used as the fuel source for engine 10, the blow-by gases may include, for example, sulfur, etc. The crankcase 14 may include a crankcase ventilation system 20 configured to purge blow-by gases from the crankcase 14. The crankcase ventilation system 20 may be an inlet/outlet breather system for purging blow-by gases from the crankcase 14. In one embodiment, the crankcase ventilation system 20 may be a non-ingestion ventilation system. As used herein, a "non-ingestion ventilation system" vents blow-by gases out of the engine (e.g., to the atmosphere). As such, the crankcase ventilation system 20 may include an inlet 22 for directing ambient air into the crankcase 14 and an outlet 24 for exhausting blow-by gases from the crankcase 14 and from the engine 10 to the atmosphere. Therefore, the discharged blow-by gas may not be reintroduced into the combustion process of the engine 10. The outlet 24 may include a filtration system that filters the blow-by gas prior to exiting the outlet 24. In one embodiment, as described in further detail below, the inlet 22 may be a heated inlet configured to direct heated ambient air into the crankcase 14. As shown in fig. 1, the inlet 22 may include a single inlet and the outlet 24 may include a first outlet 24a and a second outlet 24b such that the outlet 24 is a dual outlet. It should be appreciated that the crankcase ventilation system 20 may include any number of inlets and/or outlets (as desired).

FIG. 2 is a perspective view of a heated inlet 22 of a crankcase ventilation system 20 isolated from engine 10. As shown in fig. 2, the heated inlet 22 may include an air filter 26, a jacketed heat exchanger 28, and an inlet hose 30. As used herein, a "jacketed heat exchanger" includes an outer shell that surrounds a component to form a cavity between the outer shell and the component such that a fluid may flow through the cavity to transfer heat between the fluid and the component. The heated inlet 22 may further include a positive pressure system 32 for directing ambient air into the air filter 26. The positive pressure system 32 may be, for example, a blower, fan, or the like, such that ambient air is "pushed" through the crankcase ventilation system 20. Air filter 26 may be in fluid communication with positive pressure system 32 and may be located downstream of positive pressure system 32. For example, air filter 26 may include an inlet 25 coupled to an outlet of positive pressure system 32. Air filter 26 may include a fibrous or porous material for removing solid particulates (e.g., dust, pollen, mold, bacteria, etc.) from ambient air. For example, the air filter 26 may include a paper filter, a foam filter, a cotton filter, and the like. The air filter 26 may also include an outlet 27 located downstream of the fibrous or porous material. It should be appreciated that air filter 26 may include any type of filter known in the art for removing solid particulates from ambient air. Further, although the exemplary embodiment includes a positive pressure system 32, the crankcase ventilation system 20 may include a negative pressure system for directing ambient air into the air filter 26 and through the crankcase ventilation system 20. For example, a vacuum (e.g., a fan or pump) may be coupled to and in fluid communication with the outlet 24 of the crankcase ventilation system 20 such that air is "drawn" from the heated inlet 22 through the crankcase ventilation system 20, passes through the crankcase 14, and exits from the outlet 14.

The jacketed heat exchanger 28 may be in fluid communication with the air filter 26 and may be located downstream of the air filter 26. Jacketed heat exchanger 28 may be, for example, a shell and tube heat exchanger. As such, the jacketed heat exchanger 28 may include a shell inlet 34, a shell outlet 36, a tube-side inlet 38, and a tube-side outlet 40. The tube-side inlet 38 may be coupled (directly or through a hose/conduit) to the outlet 27 of the air filter 26 and thus in fluid communication with the air filter 26. The jacketed heat exchanger 28 may also include a tube-side inlet plenum 42 and a tube-side outlet plenum 44. As described in further detail below with reference to fig. 3, the tube-side inlet plenum 42 and the tube-side outlet plenum 44 may comprise a generally frustoconical shape for directing ambient air into and out of the one or more tubes 54. As described in further detail below, the shell inlet 34 may be coupled to and in fluid communication with the hose 46, and the shell outlet 36 may be coupled to and in fluid communication with the hose 48 for circulating a fluid through the jacketed heat exchanger 28 to heat the filtered ambient air to a desired temperature. In one embodiment, the fluid may be engine coolant. As used herein, an "engine coolant" is a water-based liquid that may be mixed with an antifreeze additive. For example, hoses 46, 48 may be coupled to a cooling system 47 of engine 10 for providing engine coolant to jacketed heat exchanger 28 to heat the filtered ambient air. The cooling system 47 may be a first cooling system of the engine 10, and the engine 10 may include a second cooling system. The cooling system 47 may be a high temperature cooling system such that the temperature of the engine coolant may include high temperatures throughout the cooling system 47. For example, during operation of the engine 10, the temperature of the engine coolant in the cooling system 47 may be in the range of eighty degrees Celsius (80℃.) to one hundred twenty degrees Celsius (120℃.) throughout the cooling system 47.

Hose 46 may be coupled to and in fluid communication with cooling system 47 at a first location, and hose 48 may be coupled to and in fluid communication with cooling system 47 at a second location downstream of the first location. For example, the hose 46 may be coupled to a casting of the cooling system 47 downstream of and adjacent to a water pump of the cooling system 47 (e.g., for pumping engine coolant). The hose 48 may be coupled to a water manifold of the cooling system 47 upstream of an outlet of the cooling system 47. Thus, engine coolant may flow in one direction from the hose 46 through the jacketed heat exchanger 28 and then through the hose 48. Further, the hose 46 may be positioned and arranged below the shell inlet 34 of the jacketed heat exchanger 28, and the hose 48 may be positioned and arranged above the shell outlet 36 of the jacketed heat exchanger 28. In this way, air pockets are prevented from forming in the hose 48, the jacketed heat exchanger 28 and the hose 46 when the engine 10 is in operation. Further, when the engine 10 is off, engine coolant may be discharged from the hose 48, the jacketed heat exchanger 28, and the hose 46 (from hose 48 to hose 46).

A crankcase inlet hose 30 may be in fluid communication with the jacketed heat exchanger 28 and located downstream of the jacketed heat exchanger 28. As such, the inlet hose 30 may be coupled at one end to the tube-side outlet 40 of the jacketed heat exchanger 28. The inlet hose 30 may also be coupled at another end to an inlet 50 or air intake of the crankcase 14. Accordingly, as described in further detail below, the inlet hose 30 may be configured to direct heated ambient air from the jacketed heat exchanger 28 into the crankcase 14. The inlet hose 30 may comprise a material such as silicone or the like for providing insulation to the heated ambient air. It should be appreciated that any type of material may be used for the inlet hose 30 to provide insulation for the heated ambient air.

Fig. 3 is an exploded perspective view of jacketed heat exchanger 28 isolated from engine 10. As shown in fig. 3, the jacketed heat exchanger 28 may include a shell 52 for receiving coolant and directing the coolant through the jacketed heat exchanger 28 via the shell inlet 34 and the shell outlet 36. For example, the shell inlet 34 may be located at a first end and on a first side of the shell 52. The shell outlet 36 may be located at a second end and on a second side of the shell 52, the second end and the second side being opposite the first end and the first side, respectively. The jacketed heat exchanger 28 may further comprise a bundle of one or more tubes 54 or conduits for receiving and directing filtered ambient air through the jacketed heat exchanger 28.

The bundle of one or more tubes 54 may include end plates 55, 57 and one or more baffles 56 for directing coolant flow through the shell 52 and around each of the one or more tubes 54. Each of the end plates 55, 57 and the one or more baffles 56 may include one or more apertures 58 for receiving a respective one of the one or more tubes 54, thereby binding the one or more tubes 54 into a single structure. Each of the one or more baffles 56 may comprise a generally semi-circular shape. The one or more baffles 56 may be arranged such that the semicircular openings are offset with respect to each other. For example, the first and third baffles 56 may be arranged such that the semicircular openings are oriented in a first direction, and the second and fourth baffles 56 may be arranged such that the semicircular openings are oriented in a second direction opposite the first direction. Thus, the one or more baffles 56 may provide a serpentine path for the coolant from the shell inlet 34 to the shell outlet 36 to distribute the coolant around each of the one or more tubes 54. It should be appreciated that any number of baffles 56 including any shape may be used and may be arranged in any pattern for directing the flow of coolant through the shell 52 and around the one or more tubes 54.

The bundle of one or more tubes 54 may be sized to be inserted into the shell 52 such that there is a gap between the shell 52 and the one or more tubes 54, and between the individual tubes 54. Further, the end plates 55, 57 may be sized to fit within the shell 52 with minimal clearance to seal against the inner surface of the shell 52. For example, when a bundle of one or more tubes 54 is inserted into the shell 52, the end plates 55, 57 may be positioned behind the shell inlet 34 and shell outlet 36, respectively, such that coolant does not flow into the inlet or outlet of the one or more tubes 54. A shell 52 having one or more tubes 54 may be coupled at one end to the tube-side inlet plenum 42 and at the other end to the tube-side outlet plenum 44. For example, the tube-side inlet plenum 42 may be located near the shell outlet 36 and the tube-side outlet plenum 44 may be located near the shell inlet 34. It should be understood that the shell 52, the tube-side inlet plenum 42, and the tube-side outlet plenum 44 may be separate components of the jacketed heat exchanger 28 such that the bundle of one or more tubes 54 may be removed from the shell 52 for maintenance or replacement. However, the shell 52, the tube-side inlet plenum 42, and the tube-side outlet plenum 44 may be formed as a single structure. Thus, the jacketed heat exchanger 28 may be a straight tube heat exchanger including a single pass tube side flow (e.g., the tube side inlet 38 is on a first side and the tube side outlet 40 is on a second side different from the first side). However, the jacketed heat exchanger 28 may be a U-tube heat exchanger, wherein one or more tubes 54 comprise a "U" shape such that the tube-side inlet 38 and the tube-side outlet 40 are on the same side. The jacketed heat exchanger 28 may also be a straight tube heat exchanger comprising a two pass tube side flow, wherein the tube side inlet 38 and the tube side outlet 40 are located on the same side, and ambient air enters through the first set of tubes 54 and exits through the second set of tubes 54.

INDUSTRIAL APPLICABILITY

The disclosed heated inlet 22 of the crankcase ventilation system 20 of the present disclosure may be used with the crankcase 14 of any internal combustion engine 10 that utilizes gaseous fuel as a fuel source.

Fig. 4 provides a flow chart depicting an exemplary method 400 for ventilating the crankcase 14 of the internal combustion engine 10 that employs natural gas as a fuel source. In step 405, ambient air may be filtered through air filter 26. For example, ambient air may be directed into air filter 26 by a positive pressure system 32 (e.g., a fan or blower) or a negative pressure system (e.g., a fan or pump).

In step 410, the filtered ambient air may be heated by the jacketed heat exchanger 28. For example, filtered ambient air may be directed from the air filter 26 through the tube-side inlet 38 into the tube-side inlet plenum 42. The tube-side inlet plenum 42 may direct filtered ambient air into each of the one or more tubes 54. As the filtered ambient air passes through the one or more tubes 54, the filtered ambient air may be heated by directing engine coolant through the shell 52 and around the one or more tubes 54. In this way, coolant may be directed from the engine cooling system into the shell 52 and into the shell inlet 34. The coolant may flow from the shell inlet 34 around the one or more tubes 54 and exit the shell 52 through the shell outlet 36. As detailed above, the coolant may be directed around the one or more tubes 54 by one or more baffles 56. Thus, as the filtered ambient air flows through the one or more tubes 54, the coolant may heat the filtered ambient air. In this way, the temperature of the filtered ambient air at the tube-side outlet 40 may be higher than the temperature of the filtered ambient air at the tube-side inlet 38. In one embodiment, the filtered ambient air may be heated by the jacketed heat exchanger 28 such that the temperature of the filtered ambient air at the tube-side outlet 40 is at least fifty-five degrees celsius (55 ℃). In one embodiment, the filtered ambient air may be heated by the jacketed heat exchanger 28 such that the temperature of the filtered ambient air at the tube-side outlet 40 is in the range of fifty-five degrees Celsius (55 ℃) to one hundred and ten degrees Celsius (110 ℃).

In step 415, heated ambient air may be directed through the inlet 50 of the crankcase 14 to purge blow-by gases, including natural gas, from the crankcase. For example, heated ambient air may exit one or more tubes 54 into the tube-side outlet plenum 44. The tube-side outlet plenum 44 may direct heated ambient air through the tube-side outlet 40 into the inlet hose 30. The inlet hose 30 may direct heated ambient air through the inlet 50 and into the crankcase 14. The heated ambient air may mix with the blow-by gases in the crankcase 14 to purge the blow-by gases from the crankcase 14, and the air-gas mixture may then exit the engine 10 through the outlet 24.

The heated inlet 22 of the crankcase ventilation system 20 of the present disclosure may help purge corrosive fumes (e.g., sulfur) from the crankcase 14, including blow-by gases of natural gas. In addition, the jacketed heat exchanger 28 of the heated inlet 22 may heat the filtered ambient air to prevent the formation of harmful acids in the crankcase 14 from the corrosive fumes blowing out of the gas (including natural gas). Additionally, utilizing the coolant of the existing cooling system 47 of the engine 10 may provide a system that automatically maintains the proper temperature of the jacketed heat exchanger 28 by using existing engine cooling controls. Further, the disclosed system may avoid the need for a separate heating system to heat the filtered ambient air for the jacketed heat exchanger 28.

It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed system without departing from the scope of the disclosure. Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.