Internal combustion engine with purge system

Abstract

Apparatuses, systems, and methods including an internal combustion engine are disclosed. The internal combustion engine can include an engine block defining a combustion cylinder and a crankcase, a piston movable within the combustion cylinder, a cylinder head coupled to the engine block adjacent to the combustion cylinder and in fluid communication therewith, and a purge system. The purge system can be in fluid communication with the crankcase. The purge system can supply air to the crankcase and the cylinder head. The purge system can include a valve cover coupled to the cylinder head, a breather coupled to the valve cover, and a flue gas treatment line coupled with the breather. The flue gas treatment line can transport flue gas from the breather away from the cylinder head.

Description

Technical Field

[0001] This disclosure relates to internal combustion engines, such as those used in vehicles or for stationary power generation. More specifically, this disclosure relates to internal combustion engines having a ventilation system for diluting unburned exhaust gases. Background Technology

[0002] Machinery, such as agricultural, industrial, construction, or other heavy machinery, can be propelled by one or more internal combustion engines. Internal combustion engines can also be used for other purposes, such as generating electricity. An internal combustion engine burns a mixture of air and fuel in cylinders, thereby producing driving torque and power. A portion of the combustion gases (referred to as "leakage") may escape from the combustion chamber across the piston and into undesirable areas of the engine, such as the crankcase. Leakage may contain unburned fuel and explosive gases. In rare cases, unburned fuel and / or explosive gases may accumulate within the engine, such as in the crankcase. If unburned fuel and / or explosive gases are not properly mitigated, such as by a safety valve, they may cause an explosion. Crankcase ventilation systems are known in internal combustion engines for venting leakage from the crankcase. For example, U.S. Patent Application Publication No. 2011 / 0277733 discloses an example of a crankcase ventilation system. However, U.S. Patent Application Publication No. 2011 / 0277733 recirculates leaked gas back into the combustion chamber of the engine block, preventing it from being transmitted to the environment from the cylinder head via specialized components such as a breather. Furthermore, the ventilation system in U.S. Patent Application Publication No. 2011 / 0277733 does not direct exhaust gases into the cylinder head. Summary of the Invention

[0003] In an example according to this disclosure, an internal combustion engine is disclosed. The internal combustion engine may include an engine block defining a combustion cylinder and a crankcase, a piston movable within the combustion cylinder, a cylinder head adjacent to and fluidly connected to the engine block, and a purging system. The purging system may be in fluid communication with the crankcase. The purging system may supply air to the crankcase and the cylinder head. The purging system may include a valve cover connected to the cylinder head, a breather connected to the valve cover, and a flue gas treatment line connected to the breather. The flue gas treatment line may deliver flue gas from the breather away from the cylinder head.

[0004] In another example according to this disclosure, a method for diluting combustion products with compressed air in an internal combustion engine is disclosed. The method may include directing compressed air from an intake manifold of the internal combustion engine to a crankcase of the internal combustion engine; conveying the compressed air from the crankcase to a plurality of cylinder heads of the internal combustion engine; conveying flue gas, together with the compressed air, from each of the plurality of cylinder heads through a dedicated breather among a plurality of breathers to a collection line; and conveying the flue gas along the collection line from the plurality of breathers to an outlet.

[0005] In another example according to this disclosure, a purging system for supplying compressed air to an internal combustion engine is disclosed. The system may include an inlet configured to connect to an intake manifold of the internal combustion engine and supply compressed air from the intake manifold to the crankcase of the internal combustion engine; a valve cover configured to connect to the cylinder head of the internal combustion engine; a breather configured to connect to the valve cover; and a flue gas treatment line configured to connect to the breather, wherein the flue gas treatment line is configured to deliver flue gas from the breather away from the cylinder head. Attached Figure Description

[0006] In accompanying drawings that are not necessarily drawn to scale, similar numbers may describe similar parts in different views. Similar numbers with different letter suffixes may represent different instances of similar parts. The accompanying drawings generally illustrate the various embodiments discussed in this document by way of example rather than limitation.

[0007] Figure 1 This is a schematic diagram depicting an exemplary internal combustion engine including a purging system according to an example of this disclosure.

[0008] Figure 2 yes Figure 1 The second schematic diagram of the engine and purging system.

[0009] Figure 3 It is based on the example of this disclosure. Figure 1 and 2 A perspective view of the engine section with a purging system.

[0010] Figure 3A yes Figure 3 Cross-sectional view of the engine and purging system.

[0011] Figure 4 This is a perspective view of components of a purging system according to another example of this disclosure.

[0012] Figure 5This is a graph showing the breather flow rate of each of the four engines over both the new engine and end-of-life (EOL) timeframes, according to an example of this disclosure, with and without a purging system, in both the new engine and EOL scenarios.

[0013] Figure 6 This is a graph showing the fuel volume percentage of multiple rocker boxes having outlets leading to flue gas treatment pipelines at three different locations, according to an example of this disclosure. Detailed Implementation

[0014] Examples of this disclosure relate to internal combustion engines, and specifically to systems and methods for supplying air to an internal combustion engine to dilute volatile fumes within the engine. Examples of this disclosure are now described with reference to the accompanying drawings. The following description is merely exemplary in nature and is not intended to limit the disclosure, its application, or its use. The described examples illustrate specific components, apparatus, and methods to provide an understanding of embodiments of this disclosure. It will be apparent to those skilled in the art that specific details are not required and that examples may be embodied in many different forms. Therefore, the examples provided should not be construed as limiting the scope of the claims.

[0015] As used herein, a component referred to as “located at,” “engaged to,” “connected to,” or “attached to” another component may be directly located at, engaged to, connected to, or attached to another component without intermediate components, or may have intermediate components to be indirectly located at, engaged to, connected to, or attached to another component. In some cases, this disclosure distinguishes between components that are directly located at, engaged to, connected to, or attached to another component and components that are indirectly located at, engaged to, connected to, or attached to another component.

[0016] Figure 1 An example schematic diagram of an engine 100 according to this disclosure is depicted. Engine 100 can be used for power generation, such as for propulsion of vehicles or other machinery. Engine 100 can include various power generation platforms, including, for example, internal combustion engines (whether gasoline, natural gas, or diesel type). It should be understood that this disclosure is applicable to any number of piston-cylinder arrangements and various engine configurations, including but not limited to V-type engines, inline engines, and horizontally opposed engines, as well as overhead cam and body cam configurations.

[0017] In some applications, the internal combustion engine disclosed herein is intended for gas compression. Therefore, in some examples, the internal combustion engine can be used in stationary applications. In other applications, the disclosed internal combustion engine can be used with vehicles and machinery, including those relevant to various industries such as construction, agriculture, forestry, transportation, materials handling, waste management, etc.

[0018] Engine 100 may include a purge system 102, engine block 104, crankcase 106, combustion cylinders 108, cylinder head 110, rocker arm box 112, valve cover 114, breather 116, and flue gas treatment passage 118. Purge system 102 may include a turbocharger 120, aftercooler 122, intake manifold 124, and inlet passage 126. Inlet passage 126 may include a check valve 128 or other valves configured to prevent backflow when the pressure within intake manifold 124 is lower than the pressure within crankcase 106. However, a check valve 128 is not required in all examples due to operational standards such as load and boost levels.

[0019] exist Figure 1 In the example, the purge system 102 may be part of the original manufacture of the engine 100 or may be a retrofit system added to the engine 100 during maintenance, upgrades, etc. As will be discussed in further detail later, the purge system 102 may be in fluid communication with the crankcase 106, for example, via inlet passage 126. The purge system 102 may be configured to supply air to the crankcase 106 and to the cylinder head 110 via the engine block 104 or via other components (not shown). The air supplied by the purge system 102 may be used to ventilate the crankcase 106 and other components (e.g., cylinder head 110, rocker arm case 112, etc.). This ventilation may dilute unburned fuel, explosive gases, and / or volatiles below the lower explosive limit, thereby preventing or reducing the possibility of an explosion within the engine 100. For simplicity, unburned fuel, explosive gases, other volatiles, and air (including the air supplied by the purge system) are collectively referred to herein as “flue gas” in some cases.

[0020] The purging system 102 may include connection pathways (some in...) Figure 1 (As specifically shown and referenced herein), the passage is in fluid communication with the flue gas treatment passage 118 via engine block 104, crankcase 106, cylinder head 110, rocker arm box 112, valve cover 114, and / or breather 116. The terms “one passage,” “multiple passages,” “one connection,” “multiple connections,” “one line,” or “multiple lines” as used herein should be interpreted broadly. These terms may be features defined by the various components of the engine shown in the figures, or may be formed by additional components known in the art (e.g., hoses, pipes, manifolds, cavities, etc.). In some examples, these additional components may be external to engine 100. As further described herein, the passage may also connect turbocharger 120, aftercooler 122, and intake manifold 124.

[0021] The purging system 102 may include channels / pipelines and other components, such as Figure 1The components shown. Air used for purging system 102 (in Figure 1 Air (designated "A") can be collected at the intake and delivered to turbocharger 120. Air from the intake can be obtained from the atmosphere or other sources. Air can be delivered to turbocharger 120, which can be configured to receive and compress air. Compressed air can be delivered from turbocharger 120 to aftercooler 122. Therefore, aftercooler 122 can be in fluid communication with turbocharger 120. Aftercooler 122 can be configured to receive and cool compressed air.

[0022] Air can be supplied from the aftercooler 122 to the intake manifold 124. The intake manifold 124 can be in fluid communication with the aftercooler 122. The intake manifold 124 can be configured to include intake air (in Figure 1 The first portion of the compressed air (designated as "IA") is delivered to the cylinder head 110 and the second portion of the compressed air, including ventilation or purging air, is delivered to the crankcase 106.

[0023] like Figure 1 As shown, the purging system 102 may include an inlet passage 126 that connects from the intake manifold 124 to the engine block 104 (in fluid communication with the crankcase 106). Therefore, the inlet passage 126 allows fluid communication between the intake manifold 124 and the crankcase 106. In addition to the crankcase 106 and the combustion cylinders 108, the engine block 104 may also form one or more internal passages 130A. These one or more internal passages 130A may communicate with the crankcase 106 and may allow some or all of the air from the purging system 102 to be delivered through the engine block 104 to the cylinder head 110 and / or the rocker arm box 112. For example, one or more internal passages 130A may include one or more drain chambers or other lines. For example, one or more internal passages 130A may be in fluid communication with one or more internal passages 130B of the cylinder head 110 and / or the rocker arm box 112. One or more internal passages 130B may include drain chambers, etc.

[0024] Engine block 104 may include a housing and may form a crankcase 106, a combustion cylinder 108, one or more internal passages 130A, and Figure 1 Other features not specifically shown herein. The combustion cylinder 108 may be configured to house one or more pistons (not shown). Each piston may be movable within the combustion cylinder 108 and may be coupled to a shaft (not shown) within the crankcase 106. Movement of the shaft may facilitate reciprocating movement of the piston within the combustion cylinder 108. Although referred to herein as a cylinder, the combustion cylinder 108 may have other shapes known in the art.

[0025] The cylinder head 110 may be connected to the engine block 104 adjacent to the piston and combustion cylinder 108. As is known in the art, the cylinder head 110 may define a portion of the combustion chamber (together with the combustion cylinder 108), intake passage, outlet passage for combustion products, valve housing, other passages, etc.

[0026] The rocker arm box 112 can be positioned on the cylinder head 110 such that the cylinder head 110 can be positioned between the rocker arm box 112 and the engine block 104, which includes the combustion cylinders 108. The rocker arm box 112 can be part of the cylinder head 110 or can be attached to the cylinder head directly or indirectly as an additional component. Therefore, according to some examples, the rocker arm box 112 can be configured to be attached to the cylinder head 110. Although in Figure 1 While shown as a separate component, this disclosure recognizes, based on other examples, that the rocker arm box 112 may be part of the cylinder head 110.

[0027] The rocker arm box 112 may include components, passages, and other features known in the art for an inlet valve and / or an outlet valve. A valve cover 114 may be directly or indirectly coupled to the rocker arm box 112. Therefore, the valve cover 114 may be configured to be coupled to the cylinder head 110 (if the rocker arm box 112 is connected to...). Figure 1 The example is a separate component, which is then via the rocker arm box 112. The valve cover 114 may include one or more passages that are in fluid communication with the passages of the purge system 102 via the cylinder head 110 and / or the rocker arm box 112 to allow flue gas to pass through.

[0028] Breather 116 can be directly or indirectly coupled to valve cover 114. Therefore, breather 116 can be configured to be coupled to valve cover 114. Breather 116 may include mechanisms for separating oil droplets and mist from leaks to prevent oil droplets and mist contained in the leak from being carried out with the leak flow. As an example, breather 116 may include one or more separation mechanisms, such as an oil separator valve, a splash guard, a serpentine channel, a mesh, or other obstruction. Breather 116 may differ from those typically used in that it may have an outlet / connection (shown subsequently) configured to be coupled to flue gas treatment passage 118. Flue gas treatment passage may be configured to be coupled to breather 116 and may be configured with outlet 132, thereby allowing flue gas 134 to be directed to the atmosphere or another location, such as away from engine 100.

[0029] Figure 2 With Figure 1 Different levels of detail provide schematic diagrams of the engine 100 and the purging system 102. Therefore, Figure 1 Some components and features are now in Figure 2 As shown in the image. Figure 2As shown, the engine 100 may include an intake manifold 124, an engine block 104, a crankcase 106, a combustion cylinder 108, a cylinder head 110, a rocker arm box 112, a valve cover 114, a breather 116, a flue gas treatment passage 118, and an outlet 132.

[0030] Figure 2 and Figure 1 The difference is that it shows an engine 100 and the purge system 102 can have multiple of the aforementioned components. These can be arranged in parallel. Therefore, the combustion cylinder 108 can include multiple combustion cylinders 108A, 108B, 108C, 108D, 108E, 108F, 108G, and 108H. The cylinder head 110 can include multiple cylinder heads 110A, 110B, 110C, 110D, 110E, 110F, 110G, and 110H. The rocker arm box 112 can include multiple rocker arm boxes 112A, 112B, 112C, 112D, 112E, 112F, 112G, and 112H. The valve cover 114 can include multiple valve covers 114A, 114B, 114C, 114D, 114E, 114F, 114G, and 114H. The respirator 116 may include multiple respirators 116A, 116B, 116C, 116D, 116E, 116F, 116G, and 116H. The number of these components is merely exemplary.

[0031] Each of the multiple cylinder heads 110A, 110B, 110C, 110D, 110E, 110F, 110G, and 110H can be (directly or indirectly) connected to one of the multiple valve covers 114A, 114B, 114C, 114D, 114E, 114F, 114G, and 114H, and one of the multiple breathers 116A, 116B, 116C, 116D, 116E, 116F, 116G, and 116H, and one of the multiple breathers.

[0032] The purging system 102 may include multiple fluidly connected passages (shown in dashed lines) extending in parallel between and / or through the aforementioned components. These passages allow flue gas to reach the flue gas treatment passage 118 and the outlet 132 through these components. Again, as... Figure 2 As shown, the intake manifold 124 can be configured to include intake ( Figure 1 The first portion of the compressed air (as specified in "IA") is delivered in parallel passages to cylinder heads 110A, 110B, 110C, 110D, 110E, 110F, 110G and 110H, and the second portion of the compressed air, including ventilation or purging air, is delivered, for example, via inlet passage 126 to crankcase 106.

[0033] like Figure 2As shown, the flue gas treatment passage 118 can be connected in series to each of a plurality of respirators 116A, 116B, 116C, 116D, 116E, 116F, 116G, and 116H. The outlet 132 of the flue gas treatment passage 118 can be located between the two innermost respirators (here, respirators 116D and 116E) in the series of respirators 116A, 116B, 116C, 116D, 116E, 116F, 116G, and 116H.

[0034] Figure 3 A perspective view of the engine 100 is shown, and the purging system 102 is illustrated. Figure 3A It shows Figure 3 A cross-sectional view of the engine 100 and the purge system 102 is shown, illustrating a piston 200 movable within one of a plurality of combustion cylinders 108A, 108B, 108C, 108D, 108E, 108F, 108G, and 108H. The purge system 102 can facilitate airflow through the engine 100, such as... Figure 3 As indicated by the arrow. As the arrow shows, air A can pass through inlet passage 126 (only when...). Figure 3 As shown in the diagram, the air passes through crankcase 106 and from crankcase 106 through cylinder block 104 to multiple cylinder heads 110A, 110B, 110C, 110D, 110E, 110F, 110G, and 110H. As previously described, the air is diluted and becomes exhaust gas. The exhaust gas can travel from multiple cylinder heads 110A, 110B, 110C, 110D, 110E, 110F, 110G, and 110H through multiple rocker arm boxes 112A, 112B, 112C, 112D, 112E, 112F, 112G, and 112H to multiple valve covers 114A, 114B, 114C, 114D, 114E, 114F, 114G, and 114H. Flue gas can pass through multiple valve covers 114A, 114B, 114C, 114D, 114E, 114F, 114G, and 114H to reach multiple breathers 116A, 116B, 116C, 116D, 116E, 116F, 116G, and 116H. Flue gas can also pass through multiple breathers 116A, 116B, 116C, 116D, 116E, 116F, 116G, and 116H to reach flue gas treatment passage 118. The flue gas can then be conveyed along flue gas treatment passage 118 to outlet 132, such as... Figure 3 As shown in the image.

[0035] Figure 4A perspective view of a purge system 300 according to another example is shown. This purge system 300 can be retrofitted to an existing engine to provide the benefits of diluting and removing engine exhaust gases as discussed herein. The purge system 300 may include an inlet passage 126, multiple valve covers 114A, 114B, 114C, 114D, 114E, and 114F, multiple breathers 116A, 116B, 116C, 116D, 116E, and 116F, and one or more exhaust gas treatment passages 118A and / or 118B, and an outlet 132. The purge system 300 can be configured as previously referenced. Figure 1-3A As shown and described, they are assembled together. Figure 4 As shown, inlet passage 126 and flue gas treatment passages 118A and / or 118B may include lines such as hoses, tubes, etc. The number of valve covers, breathers, etc., can be varied as needed to match the number of cylinder heads of the engine. When multiple breathers 116A, 116B, 116C, 116D, 116E, and 116F are connected in series by flue gas treatment passage 118B, outlet 132 may be located in a central position, for example, between the two innermost connections of the two innermost breathers (e.g., 116C and 116D). Alternatively, outlet 132 may be located more adjacent to the end of the engine (e.g., the back / rear of the engine) between the two outermost connections of the two outermost breathers (e.g., 116E and 116F), as shown in flue gas treatment passage 118A.

[0036] Industrial applicability

[0037] In operation, engine 100 can be configured to burn fuel to generate power. Although generally efficient, a small amount of leaking air may escape from the combustion chamber across the piston and into undesirable areas of the engine, such as crankcase 106. This disclosure contemplates that purge system 102 may be in fluid communication with crankcase 106, for example, via inlet passage 126 from intake manifold 124. Purge system 102 may be configured to supply air from intake manifold to crankcase 106 and through engine block 104 or through other components (not shown) to cylinder head 110. The air supplied by purge system 102 can be used to ventilate crankcase 106 and other components (e.g., cylinder head 110, rocker arm case 112, etc.). This ventilation can dilute exhaust gases (unburned fuel, explosive gases, and / or volatiles) below the lower explosive limit, thereby preventing or reducing the possibility of an explosion within engine 100.

[0038] Figure 5 and 6Results of the inventors' research using the structures disclosed herein are provided. These studies show that, for example, the purge system 102 can be configured to supply air to the rocker arm box 112 to reduce the fuel volume percentage within the rocker arm box 112 to between 4.5% and 0% (inclusive). This can be below the lower explosive limit of the engine 100. According to some examples, the purge system 102 can be configured to supply compressed air to the crankcase 106 at a flow rate between about 8 g / s and about 30 g / s (inclusive).

[0039] Figure 5 A study is shown, graphically representing four engines with different capacities and leakage rates (measured in cumulative cubic feet per hour). The leakage rates of these engines were measured against both new and EOL engines, with and without the purge system 102. As shown, the new engine resulted in approximately a two-fold increase in engine leakage compared to the EOL engine. The graph indicates that the purge air added to the engine by the purge system 102 can be constant in the new engine compared to the EOL engine. The purge system 102 can increase leakage through the breather, as shown in Table 1. Figure 5 The respirator flow rate is measured and represented graphically in the middle.

[0040] Table 1

[0041]

[0042] The inventors also determined that the location of outlet 132 could be such that the fuel volume percentage inside rocker arm box 112 is reduced below the lower explosive limit (in Figure 6 The factors shown are LEL. Figure 6 The outlet 132 is shown in different positions, including a front position (between the two foremost respirators in a series of multiple respirators), a middle position (between the two innermost respirators in a series of multiple respirators), and a rear position (between the two last respirators in a series of multiple respirators). Figure 6 It is shown that in some cases, and for certain engines where the outlet 132 is located in the front position, the fuel volume percentage in the foremost rocker arm box 112 can exceed LEL. However, Figure 6 The middle and rear positions of outlet 132 are shown to keep the fuel volume percentage in the foremost rocker arm box 112 below LEL.

[0043] The detailed description above is intended to be illustrative, not restrictive. Therefore, the scope of this disclosure should be determined by reference to the appended claims and the full scope of their equivalents.

Claims

1. An internal combustion engine, comprising: Engine blocks that limit the number of combustion cylinders and crankcases; A movable piston within each of the plurality of combustion cylinders; A plurality of cylinder heads, each of the plurality of cylinder heads being adjacent to at least one of the plurality of combustion cylinders and being fluidly connected to the engine block with respect to at least one of the plurality of combustion cylinders; as well as A purging system in fluid communication with the crankcase, wherein the purging system supplies air to the crankcase and the plurality of cylinder heads, the purging system comprising: Multiple valve covers, each of the multiple valve covers being connected to one of the multiple cylinder heads; Multiple respirators, each of the multiple respirators being coupled to one of the multiple valve covers; and A flue gas treatment line connected in series with all of the plurality of breathers, wherein the flue gas treatment line delivers flue gas from all of the plurality of breathers away from each of the plurality of cylinder heads to an outlet that releases the flue gas away from the engine.

2. The internal combustion engine according to claim 1, wherein the purging system further comprises: A turbocharger configured to receive and compress air; An aftercooler that is in fluid communication with the turbocharger and receives compressed air therefrom; An intake manifold in fluid communication with the aftercooler, wherein the intake manifold delivers a first portion of compressed air, including intake air, to the cylinder head and a second portion of compressed air, including air, to the crankcase. as well as Air is delivered from the intake manifold to the crankcase through the intake lines around the end of the engine.

3. The internal combustion engine according to claim 2, wherein the intake line includes a check valve.

4. The internal combustion engine of claim 1, wherein the flue gas treatment line has an outlet located between the two innermost breathers in a series of the plurality of breathers.

5. The internal combustion engine according to claim 1, wherein the cylinder head includes a rocker arm box, and wherein the valve cover is directly connected to the rocker arm box.

6. The internal combustion engine of claim 5, wherein the purging system supplies air to the rocker arm box to reduce the fuel volume percentage in the rocker arm box to between 4.5% and 0%, including the extreme values.

7. The internal combustion engine of claim 1, wherein the purging system supplies air to the crankcase at a flow rate between 8 g / s and 30 g / s, the numerical range of 8 g / s to 30 g / s including the extreme values.

8. A method for diluting combustion products with compressed air in an internal combustion engine, the method comprising: Compressed air is directed from the intake manifold of the internal combustion engine to the crankcase of the internal combustion engine. Compressed air is delivered from the crankcase to multiple cylinder heads of the internal combustion engine; The flue gas, along with compressed air, is delivered from each of the plurality of cylinder heads through a dedicated breather among the plurality of breathers to a collection line, which is connected in series with all of the plurality of breathers. as well as The flue gas is conveyed along the collection line from the plurality of breathers to the outlet and away from the engine.

9. The method of claim 8, wherein the outlet is located between the two innermost respirators of the plurality of respirators.

10. The method of claim 8, wherein delivering compressed air from the crankcase to the plurality of cylinder heads comprises maintaining the fuel volume percentage in the rocker arm box of each of the plurality of cylinder heads between 4.5% and 0%, including end values.

11. The method of claim 8, wherein directing compressed air from the intake manifold of the internal combustion engine to the crankcase comprises supplying compressed air to the crankcase at a flow rate between 8 g / s and 30 g / s, the numerical range between 8 g / s and 30 g / s including the extreme values.

12. A purging system for supplying compressed air to an internal combustion engine, the system comprising: An inlet, configured to connect to the intake manifold of the internal combustion engine and supply compressed air from the intake manifold to the crankcase of the internal combustion engine; A plurality of valve covers, each of the plurality of valve covers being configured to be connected to one of a plurality of cylinder heads of the internal combustion engine; A plurality of respirators, each of the plurality of respirators being configured to be coupled to one of the plurality of valve covers; as well as A flue gas treatment line configured to be connected in series with all of the plurality of breathers, wherein the flue gas treatment line is configured to deliver flue gas from all of the plurality of breathers away from each of the plurality of cylinder heads to an outlet that releases the flue gas away from the engine.

13. The purging system of claim 12, wherein the inlet includes a check valve.

14. The purging system of claim 12, wherein the flue gas treatment line has an outlet located between the two innermost breathers in a series of the plurality of breathers.

15. The system of claim 12, wherein the purging system is configured to supply compressed air to the rocker arm box to reduce the fuel volume percentage in the rocker arm box of each cylinder head to between 4.5% and 0%, including end values.

16. The system of claim 12, wherein the purging system is configured to supply compressed air to the crankcase at a flow rate between 8 g / s and 30 g / s, the numerical range of 8 g / s to 30 g / s including the extreme values.

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