Engine system and crankcase ventilation system

Abstract

An engine system includes an engine, an intake manifold coupled to the engine, and a crankcase ventilation system coupled to the engine. The intake manifold includes a throttle valve disposed therein. The crankcase ventilation system includes a flow loop system including a first inlet and a first outlet. The first inlet is fluidly coupled to the engine and is configured to receive blow-by gas from the engine. The first outlet is fluidly coupled to the intake manifold downstream of the throttle valve.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to a gas-liquid separation system for an internal combustion engine system. More specifically, the present disclosure relates to a crankcase ventilation system for separating oil from engine crankcase blow-by gases (“blow-by”).

[0002] BACKGROUND

[0003] Internal combustion engine systems require oil to lubricate moving parts. During engine operation, blow-by is produced by combustion gases that leak past the piston rings and into the engine crankcase. Blow-by in the engine crankcase includes pressurized gases loaded with oil droplets (e.g., aerosols, etc.). Such blow-by can pressurize the crankcase, increasing the risk of particulate and gas emissions from the crankcase to the surrounding environment. The amount of blow-by produced by an engine system can depend on the arrangement of the crankcase ventilation system and can vary under different engine operating conditions (e.g., as a function of crankcase pressure).

[0004] In some jurisdictions, emissions regulations have been implemented that prohibit any gas from being emitted from the engine crankcase and limit the maximum pressure in the crankcase during engine system operation to be equal to or below atmospheric pressure (e.g., NS6 emissions requirements of GB 17691-2018). Existing engine systems can include a crankcase ventilation system and a device for filtering oil droplets from blow-by gases exiting the crankcase. These systems remove oil aerosols from the blow-by and return the separated oil to the engine crankcase. The separated blow-by, with a reduced amount of oil, can be released to the atmosphere (e.g., in an open crankcase ventilation system) or returned to the engine system, e.g., via an air inlet of the engine system (e.g., a closed crankcase ventilation system), as compared to the blow-by from the crankcase. However, these systems can not maintain the crankcase pressure below atmospheric pressure over the full range of engine operating conditions. SUMMARY

[0006] One embodiment of the present disclosure relates to an engine system. The engine system includes an engine, an intake manifold coupled to the engine, and a crankcase ventilation system coupled to the engine. The intake manifold includes a throttle valve disposed therein. The crankcase ventilation system includes a flow circuit system including a first inlet and a first outlet. The first inlet is fluidly coupled to the engine and configured to receive blow-by gases from the engine. The first outlet is fluidly coupled to the intake manifold downstream of the throttle valve.

[0007] In embodiments, the engine system further includes a turbocharger configured to direct air into the intake manifold, wherein the crankcase ventilation system further includes a second outlet coupled to an inlet of the turbocharger.

[0008] In embodiments, the crankcase ventilation system further includes a crankcase ventilation device configured to separate oil from the blow-by gas received from the engine to produce a separated blow-by gas, wherein, in a first operating mode, the crankcase ventilation system is configured to direct the separated blow-by gas to the second outlet while blocking the separated blow-by gas from passing through the first outlet, and wherein, in a second operating mode, the crankcase ventilation system is configured to direct the separated blow-by gas to the first outlet.

[0009] In embodiments, the crankcase ventilation system further includes: a crankcase ventilation device; and wherein the flow circuit system further includes: a first outlet conduit fluidly coupling the crankcase ventilation device to the first outlet; and a second outlet conduit fluidly coupling the crankcase ventilation device to a second outlet.

[0010] In embodiments, the crankcase ventilation system further includes: a second inlet fluidly coupled to the intake manifold upstream of the throttle valve; and a crankcase ventilation device including a nozzle downstream of the second inlet.

[0011] In embodiments, the crankcase ventilation system further includes a crankcase ventilation device including an ejector pump disposed between the second inlet and the first outlet.

[0012] Another embodiment of the present disclosure relates to a crankcase ventilation system. The crankcase ventilation system includes a crankcase ventilation device, a first outlet conduit, and a second outlet conduit. The crankcase ventilation device includes a housing and a separator element. The housing includes a device first inlet port and a device outlet port. The separator element is disposed within the housing and is configured to separate oil from a blow-by gas received from an engine system to produce a separated blow-by gas. The first outlet conduit is fluidly coupled to the device outlet port and is configured to direct the separated blow-by gas to a first location along the engine system. The second outlet conduit is fluidly coupled to the device outlet port and is configured to direct the separated blow-by gas to a second location along the engine system.

[0013] In embodiments, in a first operating mode, the separated blow-by gas is directed entirely to the second outlet conduit, and wherein, in a second operating mode, the separated blow-by gas is directed at least partially to the first outlet conduit.

[0014] In embodiments, the first location is a first outlet configured to release the separated blow-by gas into an intake manifold of the engine system, and wherein the second location is a second outlet configured to release the separated blow-by gas into an inlet of a turbocharger of the engine system.

[0015] In embodiments, a first end of the first outlet conduit is fluidly coupled to the second outlet conduit.

[0016] In embodiments, the crankcase ventilation system further comprises a flow control system including a check valve disposed in the second outlet conduit, the check valve configured to substantially prevent flow through the check valve in a direction toward the first outlet conduit.

[0017] In embodiments, the crankcase ventilation system further comprises a flow control system including a control valve disposed in the first outlet conduit, preferably wherein the control valve is a check valve having a spring element configured to open the check valve at a threshold differential pressure across the check valve.

[0018] In embodiments, the crankcase ventilation system is configured to maintain a negative pressure in a crankcase of the engine system across an entire range of engine operating conditions for the engine system.

[0019] In embodiments, the crankcase ventilation device includes a nozzle downstream of the device second inlet port, the nozzle positioned to direct flow toward the device outlet port.

[0020] In embodiments, the crankcase ventilation device further includes a jet pump coupled to the housing, wherein the device outlet port is disposed at a pump outlet of the jet pump.

[0021] In various embodiments, a crankcase ventilation system or engine system further comprises a flow control system including: an electronic flow control valve disposed in a first outlet conduit; and a flow control unit communicably coupled to the electronic flow control valve, the flow control unit configured to open the electronic flow control valve in response to at least one of: (i) a threshold differential pressure across the electronic flow control valve; or (ii) an indication of an engine operating condition in combination with an indication that a crankcase pressure is above atmospheric pressure.

[0022] Yet another embodiment of the present disclosure relates to an electronically-controlled flow control system for use with a crankcase ventilation system. The electronically-controlled flow control system includes an electronic flow control valve and a flow control unit communicably coupled to the electronic flow control valve. The flow control unit is configured to control the electronic flow control valve based on at least one of (i) a threshold differential pressure across the electronic flow control valve or (ii) an indication of engine operating conditions in combination with an indication that the crankcase pressure is above atmospheric pressure.

[0023] In embodiments, the flow control system further includes a first pressure sensor communicably coupled to the flow control unit, the first pressure sensor configured to transmit an indication of engine crankcase pressure to the flow control unit.

[0024] In embodiments, the flow control system further includes at least one second pressure sensor communicably coupled to the flow control unit, the at least one second pressure sensor configured to transmit an indication of a differential pressure across the electronic flow control valve to the flow control unit.

[0025] In embodiments, the flow control system further includes a downstream pressure sensor communicably coupled to the flow control unit and configured to transmit an indication of intake manifold pressure to the flow control unit and an upstream pressure sensor communicably coupled to the flow control unit and configured to transmit an indication of pressure upstream of the electronic flow control valve, wherein the flow control unit is configured to transmit a control signal to the electronic flow control valve to open the electronic flow control valve based on a difference between the intake manifold pressure and the pressure upstream of the electronic flow control valve. BRIEF DESCRIPTION OF DRAWINGS

[0027] The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several embodiments in accordance with the disclosure and are not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through the use of the accompanying drawings.

[0028] Figure 1 is a schematic illustration of a crankcase ventilation system according to an embodiment.

[0029] Figure 2 is a side cross-sectional view of a crankcase ventilation device that can be used with the crankcase ventilation system of Figure 1

[0030] ​Figure 3 is a side sectional view of a check valve that can be used with Figure 1 a crankcase ventilation system and / or Figure 2 a crankcase ventilation device of

[0031] Figure 4 is a plot of engine crankcase pressure as a function of engine torque and operating speed for an open crankcase ventilation system according to an embodiment.

[0032] Figure 5 is a line plot of engine speed and engine crankcase pressure as a function of time for a closed crankcase ventilation system according to an embodiment.

[0033] Figure 6 is a plot of engine crankcase pressure as a function of engine torque and operating speed for an engine system of Figure 1

[0034] Figure 7 is a line plot of engine speed and differential pressure across a first check valve arrangement according to an embodiment that can be used with a crankcase ventilation system of Figure 1

[0035] Figure 8 is a line plot of engine speed and differential pressure across a first check valve arrangement according to an embodiment that can be used with a crankcase ventilation system of Figure 1

[0036] Figure 9 is a line plot of engine speed and differential pressure across a first check valve arrangement according to an embodiment that can be used with a crankcase ventilation system of Figure 8

[0037] Figure 10 is a schematic view of a portion of a crankcase ventilation system according to another embodiment.

[0038] Figure 11 is a block diagram of a flow control unit that can be used with a crankcase ventilation system of Figure 1 and / or Figure 10

[0039] Figure 12 is a flow chart of a method of controlling a crankcase ventilation system of Figure 1 or Figure 10

[0040] ​​​​​​In the following detailed description, reference is made to the accompanying drawings. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments can be utilized, and other changes can be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and with reference to the drawings, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and form part of this disclosure.

[0041] DETAILED DESCRIPTION

[0042] Embodiments described herein relate generally to crankcase ventilation systems and devices for internal combustion engine systems. The various concepts introduced above and below can be implemented in any of numerous ways, as the described concepts are not limited to any particular manner of implementation. Examples of specific implementations and applications are provided for illustrative purposes only.

[0043] I. OVERVIEW

[0044] Embodiments of the present disclosure relate to a crankcase ventilation system that can eliminate the need for a separate compressor to maintain the crankcase at a negative pressure (below atmospheric pressure) across the full range of engine operating conditions. The crankcase ventilation system includes a crankcase ventilation device and a jet pump configured to use a flow of pressurized air from an intake manifold to reduce the pressure in the crankcase device. The crankcase ventilation system can include two flow circuits extending from an outlet of the crankcase ventilation device. A first flow circuit extends from the outlet of the crankcase ventilation device to a location in the intake manifold of the engine system downstream of an intake valve. A second flow circuit extends from the outlet of the crankcase ventilation device to an inlet of a turbocharger for the engine system.

[0045] The crankcase ventilation system can also include a flow control valve (e.g., check valve, etc.) configured to control the flow of gas exiting through the intake manifold. At high engine speeds and / or loads, the valve is configured such that the majority of the flow passes from the crankcase ventilation device and into the turbocharger inlet. At these conditions, the turbocharger is operating at high speed and the pressure rise across the turbocharger can be greater than the case at engine idle conditions. Once the engine speed and / or load drops below a certain value, the valve is configured to switch to allow flow from the crankcase ventilation device to the intake manifold (downstream of the intake valve), which is maintained at a reduced pressure around engine idle conditions. In this way, a negative pressure can be maintained within the crankcase regardless of the operating state of the turbocharger.

[0046] It should be understood that in some embodiments, the crankcase ventilation system may include only a first flow loop, such that flow can be continuously directed to a location downstream of the intake valve in the intake manifold. Among other benefits, this will also ensure negative pressure in the crankcase near engine idling conditions without requiring a separate flow control valve downstream of the crankcase ventilation system.

[0047] II. Example Crankcase Ventilation System

[0048] Figure 1 A portion of an engine system 10 according to an embodiment is shown. The engine system 10 includes an engine 12, an intake manifold 14, and a crankcase ventilation system 100. The intake manifold 14 is coupled to the engine 12. The intake manifold 14 has a throttle valve 22 disposed therein. The crankcase ventilation system 100 is coupled to the engine 12.

[0049] Engine system 10 may also include a valve cover 13 coupled to engine 12 and a turbocharger 16 configured to deliver air 15 (e.g., filtered air, etc.) to engine 12 via intake manifold 14. Turbocharger 16 includes an inlet 17. Engine 12 includes an engine block 18 (e.g., cylinder block, etc.) and a crankcase 20 coupled to engine block 18. Engine 12 may be a diesel engine, gasoline engine, natural gas engine, dual-fuel engine, biodiesel engine, E85 engine, flex fuel engine, or another type of internal combustion engine or drive. Engine 12 can be used to power trucks, boats, locomotives, or other types of vehicles (e.g., on-road or off-road vehicles). In another embodiment, engine 12 can be used to power an electric generator (e.g., a generator set, etc.). In yet another embodiment, engine 12 can be used in industrial applications to power pumps, hydraulic systems, or other types of systems.

[0050] like Figure 1 As shown, engine block 18 defines a plurality of cylinders 19 for engine 12. Engine block 18 is coupled to crankcase 20. During operation, combustion gases can leak (e.g., blow-through) from cylinder 19 through piston rings and into crankcase 20, creating blow-through gas 21 that can pressurize crankcase 20. Over time, if blow-through gas 21 is not expelled from crankcase 20, it can cause engine oil to leak through crankshaft seals and other engine seals and gaskets. Figure 1As shown, blow-by gas 21 is discharged through a connection on valve cover 13, which is connected to the upper end of engine block 18 and encloses the overhead valve system for engine block 18. In another embodiment, blow-by gas 21 may be discharged from a connection on crankcase 20 or another suitable location.

[0051] The intake manifold 14 is connected to the engine block 18 and supplies air 15 to the cylinders 19 in the engine block 18 during engine operation. The intake manifold 14 includes conduits (e.g., passageways) that guide air 15 from other parts of the air intake system to the engine block 18. The intake manifold 14 includes a manifold inlet 26 and a manifold outlet 28 downstream of the manifold inlet 26. The intake manifold 14 also includes an intake air throttle valve, shown as a throttle valve 22, which is configured to control the amount of air 15 entering the intake manifold 14 (e.g., from the turbocharger 16), thereby regulating the pressure across the intake manifold 14. Figure 1 In one embodiment, the throttle valve 22 is positioned at an intermediate location (e.g., approximately the midpoint) between the manifold inlet 26 and the manifold outlet 28. The throttle valve 22 may include a solenoid-controlled butterfly valve. In another embodiment, the throttle valve 22 may include a torque motor (e.g., a direct-drive device) or another suitable actuator.

[0052] like Figure 1 As shown, the air intake system may further include a charge air cooler 24, which is disposed upstream of the intake manifold 14 and configured to cool the intake air 15 from the turbocharger 16. The turbocharger 16 is disposed upstream of the charge air cooler 24 and is configured to compress the intake air 15 to improve engine power output. The turbocharger 16 may include a turbine-driven forced-induction compressor driven by exhaust gases from the engine system 10. The turbocharger 16 includes an inlet 17 and an outlet 25 downstream of the inlet 17. The inlet 17 is coupled to the intake duct 30 and configured to receive air 15 from the intake duct 30. The outlet 25 of the turbocharger 16 is fluidly coupled to the charge air cooler 24.

[0053] The crankcase ventilation system 100 is configured to separate gases from blow-by gases 21 received from the engine 12 and return the separated fluid to the engine 12. The crankcase ventilation system 100 includes a flow loop system 150 having a combination of a loop, inlet, outlet, and duct. Figure 1As shown, the crankcase ventilation system 100 includes a first inlet 127, a second inlet 152, and a first outlet 129 as a flow circuit system 150. In some embodiments, as shown Figure 1 As shown, the flow circuit system 150 also includes a second outlet 133. The first inlet 127 is fluidly coupled to the engine 12 and is configured to receive blowby gas 21 from the engine 12. The second inlet 152 is fluidly coupled to the intake manifold upstream of the throttle valve 22. The first outlet 129 is fluidly coupled to the intake manifold 14 downstream of the throttle valve 22. The second outlet 133 is fluidly coupled to the intake conduit 30.

[0054] Alternatively or additionally, the crankcase ventilation system 100 includes a first outlet conduit 130 and a second outlet conduit 134 as the flow circuit system 150. The flow circuit system 150 can also include a second inlet conduit, shown as a boost line 126. The first outlet conduit 130 is fluidly coupled to the crankcase ventilation device 102 and is configured to direct the separated blowby gas 27 to a first location (e.g., the intake manifold 14 downstream of the throttle valve 22) along the engine system 10. The second outlet conduit 134 is fluidly coupled to the crankcase ventilation device 102 and is configured to direct the separated blowby gas 27 to a second location (e.g., the intake conduit 30) along the engine system 10.

[0055] The flow circuit system 150 can include a first flow circuit 128 and a second flow circuit 132, as described in more detail below. The flow circuits 128, 132 and the corresponding flow circuit system 150 can include the first inlet 127, the second inlet 152, the second outlet 133, the first outlet 129, the first outlet conduit 130, the boost line 126, and the second outlet conduit 134. The first outlet conduit 130 is connected to the second outlet conduit 134, for example, at a first end 136 of the first outlet conduit 130.

[0056] The crankcase ventilation system 100 can also include a crankcase ventilation device 102 (e.g., a gas-liquid separation assembly, a breather, etc.). The crankcase ventilation device 102 is configured to be coupled to the flow circuit system 150 that directs blowby gas 21 and separated fluid to / from the crankcase ventilation device 102. The crankcase ventilation device 102 is configured to separate liquid and gas from a fluid, such as a gas-liquid mixture, to produce separated blowby gas 27 (e.g., gas with reduced oil content compared to the blowby gas 21 from the engine 12) and liquid oil.

[0057] Figure 2 shown can be used with the crankcase ventilation system 100, the crankcase ventilation system 100, and / or the flow circuit system 150. Figure 1FIG. 1 illustrates an example of a crankcase ventilation device 102 for use with a crankcase ventilation system 100 of an engine 12. The crankcase ventilation device 102 includes a main body (shown as a housing 104) and a separator element 106. The crankcase ventilation device 102 can also include an eductor pump 108. The eductor pump 108 is coupled to the housing 104.

[0058] The housing 104 defines an internal cavity 110. The housing 104 includes a device first inlet port 112 and a device outlet port 118. The housing 104 can also define a device second inlet port 116 and a device drain 114. The device first inlet port 112 (e.g., a blow-by gas inlet, etc.) is configured to receive blow-by gas 21 (see also FIG. 1) from the engine 12. The device drain 114 is configured to return separated liquid oil to the crankcase 20. The device second inlet port 116 is configured to receive air 15 (e.g., charge air, compressed air, etc.) from the intake manifold 14, and the device outlet port 118 (e.g., a filtered gas outlet, etc.) is configured to discharge a mixture of separated blow-by gas 27 and air 15 from the housing 104. As shown, the housing 104 can be formed in multiple segments corresponding to different portions of the crankcase ventilation device 102. The segments can be welded (e.g., ultrasonically, spin welded, etc.) or otherwise coupled together to form a single component. Figure 1 Figure 2 The housing 104 defines an internal cavity 110. The housing 104 includes a device first inlet port 112 and a device outlet port 118. The housing 104 can also define a device second inlet port 116 and a device drain 114. The device first inlet port 112 (e.g., a blow-by gas inlet, etc.) is configured to receive blow-by gas 21 (see also FIG. 1) from the engine 12. The device drain 114 is configured to return separated liquid oil to the crankcase 20. The device second inlet port 116 is configured to receive air 15 (e.g., charge air, compressed air, etc.) from the intake manifold 14, and the device outlet port 118 (e.g., a filtered gas outlet, etc.) is configured to discharge a mixture of separated blow-by gas 27 and air 15 from the housing 104. As shown, the housing 104 can be formed in multiple segments corresponding to different portions of the crankcase ventilation device 102. The segments can be welded (e.g., ultrasonically, spin welded, etc.) or otherwise coupled together to form a single component.

[0059] The separator element 106 is disposed within the housing 104, such as in the internal cavity 110. The separator element 106 is configured to separate liquid oil from the blow-by gas 21 received from the engine 12 to produce separated blow-by gas 27. The separated blow-by gas 27 has a reduced oil content compared to the blow-by gas 21. The separator element 106 can include a centrifugal separator, an inertial separator, or other gas-liquid separation device.

[0060] In embodiments of the crankcase ventilation device 102, the separator element 106 includes a centrifugal pre-separator that is partially integrally formed with a lower segment of the housing 104. The blow-by gas 21 enters the lower segment tangentially to an outer periphery of the housing 104 via the device first inlet port 112. Centripetal forces separate liquid oil (e.g., oil particles and aerosols) from the blow-by gas 21 to produce partially separated blow-by gas that exits the lower segment through an axially extending fluid conduit of the separator element 106. As shown, Figure 2 Figure 2 The partially separated blow-by gas is axially moved along a middle segment (e.g., intermediate segment, etc.) of the housing 104 through the separator element 106 to an impingement separator 120 and a pressure regulator at an upper end of the separator element 106. The partially separated blow-by gas is directed against the impingement separator 120, which separates additional oil from the fluid to produce the separated blow-by gas 27. ​​

[0061] The injection pump 108 (e.g., a booster pump, etc.) is configured to reduce the pressure at the upper end of the cavity 110 to draw blow-by gas 21 from the crankcase 20, thereby maintaining the crankcase 20 at a negative pressure during engine operation. As used herein, "negative pressure" or "reduced pressure" refers to a pressure at which the engine 12 is operating that is less than or equal to atmospheric pressure (e.g., less than or equal to about 101.3 kPa at mean sea level, etc.). Figure 1 As shown, the injection pump 108 is configured to use the flow of air 15 from the intake manifold 14 to reduce the pressure at the upper end of the cavity 110. The injection pump 108 includes a pump outlet 154. A device outlet port 118 is provided at the pump outlet 154.

[0062] The crankcase ventilation device 102 includes a nozzle 122 downstream of the device's second inlet port 116. More specifically, and as... Figure 2 As shown, the jet pump 108 includes a nozzle 122. The nozzle 122 is located downstream of and near the second inlet port 116 of the device. The nozzle 122 is positioned (e.g., oriented, etc.) within the housing 104 to release gas toward the outlet port 118 of the device. Figure 2 In one embodiment, nozzle 122 is positioned to release gas from a second inlet port 116 toward a venturi element 124, which is disposed between the second inlet port 116 and the outlet port 118. Venturi element 124 includes a diverging section spaced apart from nozzle 122, which reduces the velocity of the gas exiting housing 104.

[0063] During operation, nozzle 122 increases the velocity of the pressurized gas entering the jet pump 108 through the second inlet port 116 of the device. Nozzle 122 also reduces the gas pressure at the outlet 156 of nozzle 122 (see...). Figure 2 This reduces the pressure at the upper end of the housing 104 in the space between the nozzle 122 and the venturi element 124, thereby reducing the pressure at the upper end of the housing 104.

[0064] The decrease in static pressure at the upper end of the cavity 110 of housing 104 draws blow-by gas 21 through separator element 106 into the fluid flow entering venturi element 124. The separated blow-by gas 27 then mixes with the incoming air 15 at the upper end of housing 104, and the mixture is discharged from the crankcase ventilation device 102 at the upper end of housing 104.

[0065] like Figure 1As shown, the crankcase ventilation system 100 is configured as a closed crankcase ventilation (CCV) system in which the separated blow-by gas 27 is returned to the engine 12 via an air intake system (e.g., intake manifold 14). As described above, the crankcase ventilation system 100 includes a blow-by gas inlet conduit 125 fluidly coupling the valve cover 13 to the device first inlet port 112 and configured to direct the blow-by gas 21 from the engine 12 to the crankcase ventilation device 102. The crankcase ventilation system 100 also includes an inlet fluid conduit (shown as a boost line 126) that directs air 15 (e.g., compressed air) from the intake manifold 14 to the crankcase ventilation device 102 to power the jet pump 108. As Figure 1 As shown, the inlet fluid conduit of the boost line 126 fluidly couples the device second inlet port 116 to the intake manifold 14 at a location upstream of the throttle valve 22.

[0066] In Figure 1 embodiments, the crankcase ventilation system 100 includes two flow circuits 128, 132 in a flow circuit system 150. The two flow circuits 128, 132 re-direct the separated blow-by gas 27 from the crankcase ventilation device 102 to one of the inlet 17 of the turbocharger 16 or the intake manifold 14 downstream of the throttle valve 22.

[0067] The first flow circuit 128 of the crankcase ventilation system 100 is configured to direct (e.g., channel, etc.) the separated blow-by gas 27 to a first location along the engine system 10, and the second flow circuit 132 is configured to direct the separated blow-by gas 27 to a second location along the engine system 10 that is different than the first location. In Figure 1 embodiments, the first flow circuit 128 directs the separated blow-by gas 27 from the crankcase ventilation device 102 (e.g., device outlet port 118) to a first outlet 129 of the crankcase ventilation system 100. The first outlet 129 releases the separated blow-by gas 27 into the intake manifold 14.

[0068] As Figure 1 shown, the first flow circuit 128 includes a first outlet conduit 130 (e.g., a first outlet line, a vacuum line, etc.) fluidly coupling the crankcase ventilation device 102 (e.g., device outlet port 118) to the intake manifold 14 at a location downstream of the throttle valve 22, at about half way between the throttle valve 22 and the manifold outlet 28.

[0069] The second flow circuit 132 directs the separated blow-by gas 27 from the crankcase ventilation device 102 to a second outlet 133 of the crankcase ventilation system 100. The second outlet 133 releases the separated blow-by gas 27 into the inlet 17 of the turbocharger 16.

[0070] In Figure 1 In embodiments, the second flow circuit 132 includes a second outlet conduit 134 (e.g., a second outlet line, etc.) that fluidly couples the device outlet port 118 to the intake conduit 30 upstream of the turbocharger 16 (e.g., upstream of the inlet 17 of the turbocharger 16, etc.). In Figure 1 In embodiments, the first end 136 of the first outlet conduit 130 is fluidly coupled to the second outlet conduit 134 at a location proximate the device outlet port 118. In another embodiment, the arrangement can be reversed.

[0071] In yet another embodiment, the first end 136 of the first outlet conduit 130 and the first end 155 of the second outlet conduit 134 can be fluidly coupled to an intermediate conduit that extends from the device outlet port 118. For example, the intermediate conduit can be a Y-shaped pipe or another conduit shape having a first end coupled to the device outlet port 118 and a second end coupled to both the first outlet conduit 130 and the second outlet conduit 134.

[0072] The crankcase ventilation system 100 further includes a flow control system 138 that is structured to control the flow of gas (e.g., separated blow-by gas 27) through the first flow circuit 128 and the second flow circuit 132 (e.g., to the first outlet 129 and the second outlet 133). In a first mode of operation (e.g., a first operational mode, etc.), the flow control system 138 is structured to direct the separated blow-by gas 27 to the second outlet 133 while blocking flow through the first outlet 129 (e.g., substantially independent of the first outlet 129 directing to the second outlet 133). In a second mode of operation (e.g., a second operational mode, etc.), the flow control system 138 is structured to direct the separated blow-by gas 27 to the first outlet 129 (e.g., substantially independent of the second outlet 133 directing to the first outlet 129, but not blocking flow to the second outlet 133).

[0073] The flow control system 138 can be structured to switch from the first mode of operation to the second mode of operation in response to an indication that the engine 12 is at low load and / or near idle conditions. Under these conditions, the pressure rise across the turbocharger 16 can be less than the pressure drop across the throttle valve 22. The flow control system 138 can be structured to switch from the second mode of operation to the first mode of operation in response to an indication that the engine 12 is operating at high load and / or high speed conditions. At high load and / or speed, the increased pressure rise across the turbocharger 16 provides more power to the jet pump 108 to further reduce the pressure within the crankcase 20.

[0074] As Figure 1As shown, the flow control system 138 includes a control valve 140 configured to switch the flow control system 138 between the first mode of operation and the second mode of operation. In Figure 10 In embodiments, the control valve 140 is disposed in the first outlet conduit 130, for example between the crankcase ventilation device 102 and the intake manifold 14. The control valve 140 can include a spring-actuated check valve that prevents separated blow-by gases from flowing back toward the crankcase ventilation device 102. In other embodiments, the control valve 140 can include an electronically-actuated valve (e.g., solenoid valve, etc.), such as the electronic flow control valve 202 shown in Figure 3

[0075] Figure 1 An example control valve 140 is shown in FIG. 4. The control valve 140 can be a check valve having a spring element 146 configured to open the check valve at a threshold differential pressure across the check valve. As shown, the control valve 140 includes an outer body 142 defining a passageway, a plunger 144 disposed within and movably engaged with the passageway, and a spring element 146 biasing the plunger 144 against an interior ledge of the passageway to selectively block fluid flow through the control valve 140. It will be appreciated that the design of the control valve 140 can be different in various embodiments. For example, the control valve 140 can include an electronically-actuated solenoid valve or other valve type.

[0076] As shown in FIG. 5, the flow control system 138 also includes a check valve 148 disposed in the second outlet conduit 134 downstream of the location where the first outlet conduit 130 connects to the second outlet conduit 134. The check valve 148 can include any form of mechanical or electromechanical valve that prevents backflow through the second outlet conduit 134 to ensure that sufficient air 15 is always supplied to the turbocharger. In at least one embodiment, the check valve 148 has a low opening pressure with negligible resistance to flow toward the inlet 17 of the turbocharger 16. Among other benefits, the use of a check valve 148 with a low opening pressure increases the total power available to draw blow-by gases 21 from the crankcase 20. Figure 1 In

[0077] Figures 4-7 ​​In embodiments, the flow control system 138 is configured to switch from the first operating mode to the second operating mode in response to a change in engine operating conditions (e.g., from a high load / speed engine operating condition to a low load / speed engine operating condition) and prevent the static pressure in the crankcase 20 from exceeding ambient pressure. In this way, the crankcase ventilation system 100 can adjust to changing operating conditions without the need for supplemental compressors or pumps to maintain the crankcase 20 at a negative pressure across the full range of engine operating conditions (e.g., torque, speed, load, etc.) of the engine system 10 and without the loss of efficiency of the engine 12 due to the need for electric and / or hydraulic powered compressors. The crankcase ventilation system 100 can also eliminate the need to direct power and / or hydraulic fluid to a separate compressor to maintain the crankcase 20 at a negative pressure.

[0078] The crankcase ventilation system 100 of the present disclosure has many advantages over alternative system designs. Figure 4 is a plot of observed performance data from engine testing with various arrangements of the crankcase ventilation system 100. Referring to Figure 4 , a plot of engine crankcase pressure across multiple engine operating conditions for an engine system equipped with an open crankcase ventilation system is shown. Filled (e.g., closed) circles indicate positive (e.g., above ambient) crankcase pressure, and unfilled (e.g., open) circles indicate negative (e.g., below ambient) crankcase pressure. Larger circles represent larger positive or negative pressures, respectively. The open crankcase ventilation system is configured to vent separated blow-by gases from the engine to the atmosphere, rather than returning the separated blow-by to the engine. As shown in Figure 5 , the blow-by from the engine offsets the resistance of the crankcase ventilation system, resulting in a positive crankcase pressure across the full operating range of the engine.

[0079] Figure 6 A line plot of engine speed and crankcase pressure (relative to elapsed time) for an engine including a closed crankcase ventilation system that does not include the first flow circuit 128 (e.g., returning separated blow-by to the inlet of the turbocharger of the engine system only) is shown. As shown, the turbocharger generates sufficient vacuum at high operating speeds to maintain a negative pressure in the crankcase. However, at engine idle, the vacuum generated by the turbocharger (at the turbocharger inlet) is no longer sufficient to maintain the crankcase at a negative pressure (e.g., the pressure rise across the turbocharger is very low).

[0080] Figure 7 and Figure 4 Performance of an engine system equipped with the crankcase ventilation system 100 of the present disclosure is shown. As referenced in Figure 5The filled (e.g., closed) circle indicates a positive value of crankcase pressure, while the unfilled (e.g., open) circle indicates a negative value of crankcase pressure. Larger circles represent larger positive or negative pressures, respectively. As shown, in a first operating mode (e.g., at high engine operating torque and / or speed), the flow control system directs separated blow-by gases to the turbocharger inlet, similar to the reference... Figure 6 The described layout. However, as Figure 6 As shown, once the engine operating torque and / or speed decreases sufficiently, the flow control system switches from a first operating mode to a second operating mode to redirect the flow from the crankcase ventilation system back to the first flow loop 128. Figure 7 and Figure 1 As shown, the pressure drop across the throttle valve at idle speed is sufficient to maintain the crankcase at a negative pressure.

[0081] The maximum pressure experienced in crankcase 20 during engine operation will depend in part on the opening pressure of control valve 140. The opening pressure is the pressure differential across control valve 140 when it opens (e.g., to allow detectable flow through the valve) (e.g., between device outlet port 118 and intake manifold 14 downstream of throttle valve 22). Figure 8 In this embodiment, the opening pressure of the control valve 140 depends on the design of the spring element 146 (e.g., spring load setting). The required spring load setting for the control valve 140 depends on the operating characteristics of the engine 12. For example, Figure 9 and Figure 1 A line graph showing the observed crankcase pressure and the pressure drop across control valve 140 installed in the engine system is shown. The spring load setting of control valve 140 is set to provide an opening pressure less than or equal to approximately 20 kPa, which ensures that the crankcase remains at approximately negative pressure across the entire range of engine operating conditions. Note that increasing the spring load setting of spring element 146 increases the maximum pressure in the crankcase at idle, while decreasing the spring load setting results in decreased engine idle stability (due to excessive bypass across the throttle valve).

[0082] refer to Figure 10 The design and arrangement of the components described in the embodiments should not be considered limiting. Many alternatives and combinations are possible without departing from the inventive concept disclosed herein. For example, in some embodiments, portions of the first flow loop 128 and / or the second flow loop 132 may be integrated with the crankcase ventilation device 102 (e.g., control valve 140, a flow divider between the first flow loop 128 and the second flow loop 132, etc.) (e.g., built into the crankcase ventilation device 102 (e.g., control valve 140, a flow divider between the first flow loop 128 and the second flow loop 132, etc.)).

[0083] refer toFigure 1 An alternative engine system 34 is shown, which is similar to the engine system 10 of Figure 1 and includes at least some of the same components as the engine system 10 of Figure 1 The engine system 34 includes a crankcase ventilation system 200 that includes an electronically controlled flow control system 210. The crankcase ventilation system 200 is similar to the crankcase ventilation system 100 of Figure 10 but includes an electronic flow control valve 202 (e.g., solenoid valve, etc.) in place of or in combination with the spring actuated control valve 140.

[0084] The electronically controlled flow control system 210 includes the electronic flow control valve 202 and a flow control unit 212. Thus, the crankcase ventilation system 200 includes the flow control unit 212 and a sensor system 240 used by the flow control unit 212 to control actuation of the electronic flow control valve 202.

[0085] As shown in Figure 11 , the sensor system 240 includes three separate pressure sensors that are communicably coupled to the flow control unit 212. More specifically, the sensor system 240 includes a first pressure sensor 204 (e.g., first outlet pressure sensor, downstream pressure sensor, etc.) disposed in the intake manifold 14 at a location downstream of the throttle valve 22, a second pressure sensor 206 (e.g., crankcase pressure sensor) disposed in the valve cover 13, and a third pressure sensor 208 (e.g., outlet pressure sensor, upstream pressure sensor, etc.) disposed proximate the device outlet port 118. Thus, the first pressure sensor 204 is structured to monitor and transmit an indication of the static pressure in the intake manifold downstream of the throttle valve 22. The second pressure sensor 206 is structured to monitor and transmit an indication of the static pressure in the crankcase 20. The third pressure sensor 208 is structured to monitor and transmit an indication of the static pressure at the device outlet port 118.

[0086] In example embodiments, the first pressure sensor 204 is communicably coupled to the flow control unit 212 and structured to transmit an indication of the intake manifold pressure of the intake manifold 14 to the flow control unit 212. The third pressure sensor 208 is communicably coupled to the flow control unit 212 and structured to transmit an indication of the pressure upstream of the electronic flow control valve 202. The flow control unit 212 is structured to transmit a control signal to the electronic flow control valve 202 to open the electronic flow control valve 202 based on a difference between the intake manifold pressure and the pressure upstream of the electronic flow control valve 202.

[0087] In other embodiments, the number and / or location of the pressure sensors in the sensor system 240 may vary. For example, the second pressure sensor 206 and the third pressure sensor 208 may be replaced by a single differential pressure sensor arranged to directly measure the pressure drop across the electronic flow control valve 202. The crankcase ventilation system 200 may also be configured to receive data from various sensors in the engine system 10, such as sensors that monitor the operating speed of the engine 12 (e.g., engine speed sensor 209 and / or other sensors)).

[0088] refer to Figure 11 The diagram illustrates a flow control system 210 for a crankcase ventilation system 200. The flow control system 210 is configured to control the operation of an electronic flow control valve 202 based on the operating conditions of the engine system 34. The flow control system 210 includes an electronic control unit, shown as a flow control unit 212. The flow control unit 212 includes a memory 214, a communication interface 216, and a processor 218. In other embodiments, the flow control unit 212 may include additional, fewer, and / or different components. In one embodiment, the flow control unit 212 is a separate control unit of the crankcase ventilation system 200. In another embodiment, the flow control unit 212 is a control circuit (e.g., a control module, etc.) that forms part of an engine control unit of the engine system 34.

[0089] Memory 214 may be configured to store machine-readable instructions for the flow control unit 212. The machine-readable instructions may include instructions for monitoring and storing sensor data from one or more sensors of the engine system. Additionally, the machine-readable instructions may include instructions for determining the operating conditions of the engine system 34 (such as the operating conditions of engine 12) and controlling the actuation of the electronic flow control valve 202 to maintain negative pressure in the crankcase 20. Memory 214 may also store threshold parameters of the crankcase ventilation systems 100, 200, such as the threshold pressure differential across the electronic flow control valve 202, at or above which the electronic flow control valve 202 should open.

[0090] Communication interface 216 is configured to connect flow control unit 212 to crankcase ventilation system 200 and / or other components of the engine system. For example... Figure 12 As shown, communication interface 216 is communicatively connected to electronic flow control valve 202 and configured to transmit signals (e.g., control signals) to control the operation of electronic flow control valve 202. Communication interface 216 is also communicatively connected to sensor system 240, which includes a first pressure sensor 204, a second pressure sensor 206, a third pressure sensor 208, and an engine operating speed sensor. Communication interface 216 is configured to receive sensor data from sensor system 240.

[0091] The communication interface 216 can include any type and any number of wired or wireless connections. For example, the wired connections can include serial cables, fiber optic cables, CAT5 cables, or any other form of wired connection. The wireless connections can include the internet, Wi-Fi, cellular, radio, Bluetooth, ZigBee, etc. In one embodiment, the flow control unit 212 forms part of a controller area network (CAN) bus that provides for the exchange of signals, information, and / or data between vehicle components for the engine system 34. The CAN bus includes any number of wired and wireless connections.

[0092] The processor 218 can be communicably coupled to each component of the flow control unit 212 and can be configured to control the interaction between the components. For example, the processor 218 can be configured to control the collection, processing, and transmission of sensor data for the flow control unit 212. Additionally, the processor 218 can be configured to retrieve and interpret control parameters stored in the memory 214 and control the operation of the electronic flow control valve 202 based on the sensor data and the control parameters.

[0093] Referring to Figure 11 , a flowchart illustrating a method 300 of controlling a crankcase ventilation system (such as the crankcase ventilation system 100, 200) by a flow control system (such as the flow control system 210) according to an embodiment is shown. As shown, the flow control system (e.g., the flow control system 210 of the engine system 34) Figure 12 is configured to control the electronic flow control valve 202 based on (i) a threshold differential pressure across the electronic flow control valve 202 and / or (ii) an indication of engine operating conditions in combination with an indication that the crankcase pressure is above atmospheric pressure. The algorithm for controlling the valve operation based on the differential pressure across the electronic flow control valve 202 is shown in branch 302. The flow control unit 212 receives an indication of the intake manifold pressure from the first pressure sensor 204. The flow control unit 212 also receives an indication of the CCV outlet pressure from the third pressure sensor 208 proximate the device outlet port 118.

[0094] At 304, the flow control unit 212 determines the differential pressure between the intake manifold pressure and the CCV outlet pressure (e.g., the pressure upstream of the electronic flow control valve 202), for example, by subtracting the CCV outlet pressure from the intake manifold pressure. At 306, the flow control unit 212 compares the differential pressure to a threshold differential pressure stored in a memory (e.g., the memory 214). The flow control unit 212 (e.g., using the processor 218) is configured to transmit a control signal to the electronic flow control valve 202 to open the electronic flow control valve 202 based on a determination that the differential pressure satisfies (e.g., is greater than or equal to) the threshold differential pressure.

[0095] Simultaneously, the flow control unit 212 is configured to control the electronic flow control valve 202 based on the pressure in the crankcase 20 and the engine operating speed, as indicated by the algorithm shown in branch 308. For example, the flow control unit 212 may (e.g., periodically during engine operation) receive indications from the second pressure sensor 206 regarding the pressure in the crankcase 20 and from the engine speed sensor 209 regarding the engine speed. The flow control unit 212 (e.g., using processor 218) is configured to transmit a control signal to the electronic flow control valve 202 to open the electronic flow control valve 202 based on indications that the engine 12 is running (e.g., the engine speed is above 0 RPM or at another suitable threshold) and that the pressure in the crankcase 20 has risen above atmospheric pressure.

[0096] In addition to other benefits, ​ Method 300 can also improve system performance by ensuring that the electronic flow control valve 202 opens only when necessary to keep the pressure in the crankcase 20 below atmospheric pressure, thereby reducing the risk to engine stability at idle caused by excessive bypass of the throttle valve 22 across the engine system 34.

[0097] III. Structure of Example Implementation

[0098] It should be noted that the term "example" used herein to describe various embodiments is intended to indicate that such embodiments are possible examples, representations and / or illustrations of possible embodiments (and such terms are not intended to mean that such embodiments must be particular or excellent examples).

[0099] As used herein, the term "substantially" and similar terms are intended to have a broad meaning consistent with common and accepted use by one of ordinary skill in the art to which the subject matter of this disclosure pertains. Those skilled in the art upon reviewing this disclosure will understand that these terms are intended to allow for the description of certain features described and claimed, without limiting the scope of those features to the precise numerical ranges provided. Therefore, these terms should be interpreted as indicating that non-substantial or irrelevant modifications or alterations to the described and claimed subject matter (e.g., within plus or minus five percent of a given angle or other value) are considered to be within the scope of the invention as set forth in the appended claims.

[0100] The terms "coupled," "connected," and "in communication with" and similar terms as used herein mean the joining of two members directly or indirectly. The joining can be stationary in nature (e.g., fixed attachment) or moveable in nature (e.g., removable or releasable). The joining can be achieved with the two members or the two members and any additional intermediate member being integrally formed as a single unitary body or with the two members or the two members and any additional intermediate member being attached to one another.

[0101] While the term "processor" is briefly defined above, the terms "processor" and "processing circuitry" are intended to be interpreted broadly. In this regard and as described above, a "processor" can be implemented as one or more general purpose processors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), or other suitable electronic data processing components constructed to execute instructions provided by memory. The one or more processors can take the form of a single core processor, multi-core processor (e.g., dual-core processors, tri-core processors, quad-core processors, etc.), microprocessors, etc. In some embodiments, the one or more processors can be external to the device, e.g., the one or more processors can be remote processors (e.g., cloud-based processors). Alternatively or additionally, the one or more processors can be internal and / or local to the device. In this regard, a given circuit or component thereof can be disposed locally (e.g., as part of a local server, local computing system, etc.) or remotely (e.g., as part of a remote server such as a cloud-based server). To this end, a "circuit" as described herein can include components distributed over one or more locations.

[0102] It is important to note that the constructions and arrangements of the various exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications (e.g., variations of sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) can be made without materially departing from the novel teachings and advantages of the subject matter described herein. Accordingly, all such modifications are intended to be included within the scope of the embodiments described herein. The aims and objectives of the exemplary embodiments can similarly be achieved by other specifically structured embodiments that are not expressly mentioned herein. Other substitutions, modifications, changes, and omissions can be made in the design, operating conditions, and arrangement of the various exemplary embodiments without departing from the scope of the embodiments described herein.

[0103] While the specification contains many specific implementation details, these should not be construed as limiting the scope of any embodiments or of what can be claimed, but as describing specific implementations that can be directed to particular embodiments. Certain features that are described in the context of separate implementations can also be implemented in combination. Conversely, various features that are described in the context of a single implementation can also be implemented separately or in any suitable subcombination. Moreover, although features can be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination can then be directed to a subcombination or variation of a subcombination.

Claims

1. An engine system comprising: an engine; an intake manifold (14) coupled to the engine, the intake manifold having a throttle valve disposed therein; a turbocharger configured to direct air into the intake manifold; and a crankcase ventilation system coupled to the engine, the crankcase ventilation system comprising a crankcase ventilation device and a flow circuit system, the flow circuit system comprising: - a first inlet (127) fluidly coupled to a first inlet port (112) of a housing of the crankcase ventilation device and to the engine, the first inlet configured to receive blow-by gas from the engine; - a second inlet (152) fluidly coupled to a second inlet port (116) of the housing of the crankcase ventilation device and to the intake manifold; - a first outlet (129) that is (i) fluidly coupled to the intake manifold downstream of the throttle valve, and (ii) fluidly coupled to a device outlet port (118) of the housing; and - a second outlet (133) fluidly coupled to (i) an inlet of the turbocharger, and (ii) the device outlet port of the housing, the crankcase ventilation device comprising a Venturi element disposed between the second inlet port and the device outlet port of the housing. the crankcase ventilation device configured to separate oil from the blow-by gas received from the engine to produce separated blow-by gas, 2. The engine system of claim 1, wherein, wherein, in a first mode of operation, the crankcase ventilation system is configured to direct the separated blow-by gas to the second outlet while blocking the separated blow-by gas from passing through the first outlet, and wherein, in a second mode of operation, the crankcase ventilation system is configured to direct the separated blow-by gas to the first outlet. the flow circuit system further comprising:

3. The engine system of claim 1, wherein, a first outlet conduit fluidly coupling the crankcase ventilation device to the first outlet; and a second outlet conduit fluidly coupling the crankcase ventilation device to the second outlet. the crankcase ventilation device comprising a nozzle downstream of the second inlet.

4. The engine system according to any one of claims 1 to 3, wherein, the crankcase ventilation device further comprising an ejector pump disposed between the second inlet and the first outlet.

5. The engine system of claim 4, wherein, a first end of the first outlet conduit is fluidly coupled to the second outlet conduit.

6. The engine system of claim 3, wherein, the crankcase ventilation system further comprising a flow control system comprising a check valve disposed in the second outlet conduit, the check valve configured to substantially prevent flow through the check valve in a direction toward the first outlet conduit.

7. The engine system of claim 3, wherein, the crankcase ventilation system further comprising a flow control system comprising a control valve disposed in the first outlet conduit.

8. The engine system of claim 3, wherein, the control valve is a check valve having a spring element configured to open the check valve at a threshold differential pressure across the check valve.

9. The engine system of claim 8, wherein, ​ 10. The engine system of any one of claims 1-3 and 5, wherein, The crankcase ventilation system is configured to maintain the crankcase of the engine system at a negative pressure across a full range of engine operating conditions for the engine system.

11. The engine system of claim 3, further comprising a flow control system, the flow control system comprising: an electronic flow control valve disposed in the first outlet conduit; and a flow control unit communicably coupled to the electronic flow control valve, the flow control unit configured to open the electronic flow control valve in response to at least one of: (i) a threshold differential pressure across the electronic flow control valve; or (ii) an indication of an engine operating condition in combination with an indication of a crankcase pressure above atmospheric pressure.

12. A crankcase ventilation system, comprising: a crankcase ventilation device, the crankcase ventilation device comprising: a housing comprising a device first inlet port, a device second inlet port, and a device outlet port; a separator element disposed within the housing, the separator element configured to separate oil from blow-by gas received from an engine to produce separated blow-by gas; a first outlet conduit fluidly coupled to the device outlet port and configured to direct the separated blow-by gas to a first location along an engine system; a second outlet conduit fluidly coupled to the device outlet port and configured to direct the separated blow-by gas to a second location along the engine system; and a Venturi element disposed between the device second inlet port and the device outlet port.

13. The crankcase ventilation system according to claim 12 wherein, in a first operating mode, the separated blow-by gas is directed entirely to the second outlet conduit, and wherein, in a second operating mode, the separated blow-by gas is directed at least partially to the first outlet conduit.

14. The crankcase ventilation system according to claim 12 or 13, wherein the first location is a first outlet configured to release the separated blow-by gas into an intake manifold of the engine system, and wherein the second location is a second outlet configured to release the separated blow-by gas into an inlet of a turbocharger of the engine system.

15. The crankcase ventilation system according to claim 12 or 13, wherein a first end of the first outlet conduit is fluidly coupled to the second outlet conduit.

16. The crankcase ventilation system according to claim 12 or 13, wherein the crankcase ventilation system further comprises a flow control system, the flow control system comprising a check valve disposed in the second outlet conduit, the check valve configured to substantially prevent flow through the check valve in a direction toward the first outlet conduit.

17. The crankcase ventilation system according to claim 12 or 13, wherein, the crankcase ventilation system further comprises a flow control system, the flow control system comprising a control valve disposed in the first outlet conduit.

18. The crankcase ventilation system according to claim 17 wherein, the control valve is a check valve having a spring element configured to open the check valve at a threshold differential pressure across the check valve.

19. The crankcase ventilation system according to claim 12 or 13 wherein, the crankcase ventilation system is configured to maintain the crankcase of the engine system at a negative pressure across a full range of engine operating conditions for the engine system.

20. The crankcase ventilation system according to claim 12 or 13 wherein, The crankcase ventilation device includes a nozzle downstream of the second inlet port of the device, the nozzle positioned to direct flow toward the outlet port of the device.

21. The crankcase ventilation system according to claim 12 or 13 wherein, The venturi element is part of an eductor pump coupled to the housing, wherein the device outlet port is provided at a pump outlet of the eductor pump.

22. The crankcase ventilation system of claim 12 or 13, further comprising a flow control system, the flow control system comprising: an electronic flow control valve provided in the first outlet conduit; and a flow control unit communicably coupled to the electronic flow control valve, the flow control unit configured to open the electronic flow control valve in response to at least one of: (i) a threshold differential pressure across the electronic flow control valve; or (ii) an indication of engine operating conditions in combination with an indication that the crankcase pressure is above atmospheric pressure.

23. An electronically controlled flow control system for use with the crankcase ventilation system of any of claims 12-22, the flow control system comprising: an electronic flow control valve provided in the first outlet conduit and configured to control flow between a crankcase ventilation device of the crankcase ventilation system and an intake manifold; a pressure sensor configured to generate pressure data indicative of engine-crankcase pressure; an engine speed sensor configured to generate speed data indicative of engine operating speed; and a flow control unit communicably coupled to the electronic flow control valve, the pressure sensor, and the engine speed sensor, the flow control unit configured to control the electronic flow control valve based on speed data in combination with the pressure data being above atmospheric pressure, such that in a first operating mode the separated blow-by gas is directed entirely to the second outlet conduit, and in a second operating mode the separated blow-by gas is directed at least partially to the first outlet conduit.

24. The flow control system of claim 23, further comprising at least one third pressure sensor communicably coupled to the flow control unit, the at least one third pressure sensor configured to transmit an indication of a differential pressure across the electronic flow control valve to the flow control unit, wherein the flow control unit is further configured to control the electronic flow control valve based on the differential pressure across the electronic flow control valve and a threshold differential pressure.

25. The flow control system of claim 23, further comprising: a downstream pressure sensor communicably coupled to the flow control unit and configured to transmit an indication of intake manifold pressure to the flow control unit; and a differential pressure sensor communicably coupled to the flow control unit and configured to transmit an indication of a differential pressure across the electronic flow control valve to the flow control unit. an upstream pressure sensor communicably coupled to the flow control unit and configured to transmit an indication of a pressure upstream of the electronic flow control valve, wherein the flow control unit is configured to transmit a control signal to the electronic flow control valve to open the electronic flow control valve based on a difference between the intake manifold pressure and the pressure upstream of the electronic flow control valve.

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