Claims:1. A method (400) for recovering hydrogen from a crankcase (3) of a hydrogen internal combustion engine (1), the method (400) comprising:
monitoring, by an electronic control unit [ECU] (5), quantity of hydrogen in blow-by gases accumulated within the crankcase (3) of the hydrogen internal combustion engine (1), based on signals received from a hydrogen sensor (13) associated with the crankcase (3); and
operating, by the ECU (5), a valve (11) coupled to a ventilation path (24) of the crankcase (3), to selectively channelize and store the hydrogen in a storage tank (22), fluidly connected to the ventilation path (24).

2. The method (400) as claimed in claim 1, wherein the valve (11) is operated to open condition by the ECU (5), when the quantity of hydrogen in the crankcase (3) is more than a predefined limit.

3. The method (400) as claimed in claim 1, wherein the ventilation path (24) is structured to channelize the blow-by gases through a gas separator (7) to separate hydrogen from the blow-by gases.

4. The method (400) as claimed in claim 1, comprises operating by the ECU (5), a pump (12) to route the separated hydrogen from the gas separator (7) to the storage tank (22).

5. A system (100, 200) for recovering hydrogen from a crankcase (3) of a hydrogen internal combustion engine (1), the system (100, 200) comprising:
a hydrogen sensor (13), associated with the crankcase (3), wherein the hydrogen sensor (13) is configured to generate signals corresponding to quantity of hydrogen in blow-by gases accumulated within the crankcase (3);
an electronic control unit [ECU] (5), communicatively coupled to the hydrogen sensor (13), wherein the ECU (5) is configured to:
monitor quantity of hydrogen in the blow-by gases, based on signals received from the hydrogen sensor (13); and
operate a valve (11) coupled to a ventilation path (24) of the crankcase (3), to selectively channelize and store the hydrogen in a storage tank (22), fluidly connected to the ventilation path (24).

6. The system (100, 200) as claimed in claim 5, wherein the valve (11) is operated to open condition by the ECU (5), when the quantity of hydrogen in the crankcase (3) is more than a predefined limit.

7. The system (100, 200) as claimed in claim 5comprises a gas separator (7) fluidly connected to the ventilation path, wherein the gas separator (7) is adapted to separate hydrogen from the blow-by gases.

8. The system (100, 200) as claimed in claim 7, comprises a pump (12) operatively coupled to the ECU (5), to route the separated hydrogen from the gas separator (7) to the storage tank (22).

9. The system (100, 200) as claimed in 8, wherein the storage tank (22) is at least one of an auxiliary tank (8) and a main tank (9) associated with the hydrogen internal combustion engine (1).

10. A method (500) for maintaining temperature of a catalyst chamber (23) of an exhaust after treatment unit (4) for a hydrogen internal combustion engine (1), the method (500) comprising:
determining, by an electronic control unit [ECU] (5), quantity of nitrogen oxides [NOx] in an exhaust gas from the hydrogen internal combustion engine (1), based on a signal received from a NOx sensor (16) associated with the exhaust after treatment unit (4);
determining, by the ECU (5), temperature of the catalyst chamber (23) based on signals from a temperature sensor (14) associated with the exhaust after treatment unit (4), when the determined quantity of NOx in the exhaust gas exceeds a predefined value; and
operating, by the ECU (5), a pump (20) to inject hydrogen from a storage tank (22) to a pre-ignition chamber (6), wherein the injected hydrogen is combusted in the pre-ignition chamber (6) to heat the exhaust gas, when the determined temperature of the catalyst chamber (23) is less than a predefined limit.

11. The method (500) as claimed in claim 10, comprises operating by the ECU (5), a flow control valve (15) coupled the pre-ignition chamber (6), to direct combusted hydrogen to the catalyst chamber (23) for maintaining temperature of the catalyst chamber (23) above the predefined limit.

12. The method (500) as claimed in claim 10, wherein maintaining temperature of the catalyst chamber (23) above the predefined limit increases rate of reaction between catalyst in the catalyst chamber (23) and NOx in the exhaust gas.

13. The method (500) as claimed in claim 10, comprises triggering, by the ECU (5), an ignition element associated with the pre-ignition chamber (6), to selectively combust the hydrogen injected into the pre-ignition chamber (6).

14. A system (100, 300) for maintaining temperature of a catalyst chamber (23) of an exhaust after treatment unit (4) for a hydrogen internal combustion engine (1), the system (100, 300) comprising:
a NOx sensor (16) associated with the exhaust after treatment unit (4), wherein the NOx sensor (16) is configured to generate a signal corresponding to quantity of NOx in an exhaust gas from the hydrogen internal combustion engine (1);
a temperature sensor (14) associated with the exhaust after treatment unit (4), wherein the temperature sensor (14) is configured to generate signals corresponding to temperature of the catalyst chamber (23);
an electronic control unit [ECU] (5), communicatively coupled to the NOx sensor (16) and the temperature sensor (14), wherein the ECU (5) is configured to:
operate a pump (20) to inject hydrogen from a storage tank (22) to a pre-ignition chamber (6), wherein the injected hydrogen is combusted in the pre-ignition chamber (6) to heat the exhaust gas, when the determined temperature of the catalyst chamber (23) is less than a predefined limit.

15. The system (100, 300) as claimed in claim 14, comprises a flow control valve (15) coupled with the pre-ignition chamber (6) and wherein the pre-ignition chamber (6) is positioned upstream of the catalyst chamber (23).

16. The system (100, 300) as claimed in claim 15, wherein the flow control valve (15) is operated by the ECU (5), to direct combusted hydrogen to the catalyst chamber (23) for maintaining temperature of the catalyst chamber (23) above the predefined limit.

17. The system (100, 300) as claimed in claim 16, wherein maintaining temperature of the catalyst chamber (23) above the predefined limit increases rate of reaction between catalyst in the catalyst chamber (23) and NOx in the exhaust gas.

18. The system (100, 300) as claimed in claim 14, wherein the ECU (5) is configured to trigger an ignition element associated with the pre-ignition chamber (6), to selectively combust hydrogen injected into the pre-ignition chamber (6).

19. The system (100, 300) as claimed in claim 14, wherein the ECU (5) is configured to operate a gas controller (10) associated with the pump (20) and the storage tank (22), to regulate hydrogen injection to the pre-ignition chamber (6) from the storage tank (22).

20. The system (100, 300) as claimed in claim 19, wherein the storage tank (22) is at least one of an auxiliary tank (8) and a main tank (9) associated with the hydrogen internal combustion engine (1).
, Description:TECHNICAL FIELD
The present disclosure, in general, relates to the field of automobiles. Particularly, but not exclusively, the present disclosure relates to a hydrogen internal combustion engine [that is, internal combustion engine being run by hydrogen as fuel]. Further, embodiments of the present disclosure relate to a system and a method for recovering hydrogen from a crankcase of a hydrogen internal combustion engine. In addition, embodiments of the present disclosure also relate to a system and a method for maintaining temperature of a catalyst chamber of an exhaust after treatment unit, based on the hydrogen recovered from the crankcase of such hydrogen internal combustion engine.

BACKGROUND OF THE DISCLOSURE
In general, internal combustion engines employ charge having air mixed with fuel such as, but not limited to, petroleum products or its derivatives, to suitably combust and produce energy leaving some by-products such as exhaust gases. With advent of technology, to minimize usage of non-renewable resources such as petroleum products in automotive industries at least for locomotive purposes, IC engines capable of running by alternative fuels including, but not limited to, hydrogen fuels, have been developed. The hydrogen fuel performs similar functions as that of petroleum products, however, the by-product of such IC engines includes nitrogen oxide, carbon dioxide, and water vapor traces after combustion.

Generally, IC engines including hydrogen internal combustion engines, suffer from unwanted leakage of gas under pressure into crankcase of such engines, which are generally termed as blow-by gases. Gas may leak from several sources in the hydrogen internal combustion engine, such as, but may not be limited to, cylinders, cylinder liners, piston rings, piston ring clearance, and the like. The blow-by which leak under pressure within the cylinder may generally intrude into the crankcase of the engine, and may include, but may not be limited to, hydrogen, air, burned and unburned gases, oil mist and other fluid substances that may be permeable through the piston rings, the cylinder lining and the piston. The blow-by gases, in general, cause variation in timing and/or functioning of the engine, which inherently may reduce efficiency of the engine and cause changes including, but not limited to, increase in oil/lubricant consumption. Such variation in timing and functioning of the engine may inadvertently lead to increase failure and/or safety parameters of such engine. Further, the blow-by gases may increase pressure within the crankcase, thereby affecting rate of reciprocation of pistons and other moving parts of the engine.

Conventionally, to mitigate such problems arising from blow-by gases, enclosed volume of the crankcase is periodically vented to atmosphere or may be vented during oil/lubricant replacement of engines. In hydrogen internal combustion engine, loss of hydrogen caused by blow-by, needs to be compensated with additional supply of hydrogen to the engine, which leads to increase in operational costs associated with the hydrogen internal combustion engine. In addition, to prevent problems such as, variation in timing and/or functioning of the engine and increase in oil/lubricant consumption, arising from blow-by gases accumulated in the crankcase, blow-by gases needs to be periodically vented from the crankcase.

Further, exhaust gas emitted by the IC engines include, but may not be limited to, carbon dioxide, nitrogen oxides, water vapor and other gases in negligible proportion, that may be produced due to elements and/or compounds in the air. Primarily, nitrogen oxides [or referred to as NOx] are produced as one of the by-products due to considerable amount of nitrogen gas in the air being used for combustion in the hydrogen internal combustion engine. Quantity of NOx allowable in the emission is dependent on regulatory norms of various countries in which the hydrogen internal combustion engine may be operated. In certain countries, NOx emissions from hydrogen internal combustion engines, are to be regulated to zero or a nearly zero-value that may be under regulatory pre-set value. Further, regulation of such NOx emissions needs to be performed without having to compromise on load capacity, and durability of such hydrogen internal combustion engine.

Conventionally, exhaust after treatment units are employed to reduce NOx content in exhaust gas. Exhaust after treatment units may include a catalyst chamber, configured to reduce and/or regulate quantity of NOx emissions in the exhaust gas. Temperature of the catalyst chamber greatly influences reduction and regulation of quantity of NOx emissions in the exhaust gas. To maintain an optimum reduction performance of the exhaust after treatment unit and to meet regulatory norms relating to quantity of NOx allowable in the emission, it is essential that the temperature of the catalyst chamber is maintained within a predefined temperature range. As known in the prior art, techniques such as electric heating of the catalyst chamber, varying combustion calibration strategy, adding fuel to exhaust gas, and other conventional process are employed to maintain temperature of the catalyst chamber. However, such conventional processes increase fuel consumption of the vehicle and necessitate additional equipment for power supply, which thereby leads to increase in manufacturing and operational costs associated with the hydrogen internal combustion engine. Also, accommodating such additional components in the exhaust after treatment units may render the same bulky, whereby leading to constricted environment either in an engine bay or underneath floor of the vehicle.

The present disclosure is directed to overcome one or more limitations stated above or any other limitations associated with the conventional configuration of the hydrogen internal combustion engines.

SUMMARY OF THE DISCLOSURE

One or more shortcomings of the prior art are overcome by a method and a system as claimed and additional advantages are provided through the method and the system as claimed in the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

According to a first aspect of present disclosure, a method for recovering hydrogen from a crankcase of a hydrogen internal combustion engine is disclosed. The method includes monitoring, by an electronic control unit [ECU], quantity of hydrogen in blow-by gases accumulated within the crankcase of the hydrogen internal combustion engine, based on signals received from a hydrogen sensor associated with the crankcase. The method further includes operating, by the ECU, a valve coupled to a ventilation path of the crankcase, to selectively channelize and store the hydrogen in a storage tank, fluidly connected to the ventilation path.

In an embodiment of the present disclosure, the valve is operated to open condition by the ECU, when the quantity of hydrogen in the crankcase is more than a predefined limit.

In an embodiment of the present disclosure, the ventilation path is structured to channelize the blow-by gases through a gas separator to separate hydrogen from the blow-by gases.

In an embodiment of the present disclosure, the method includes operating by the ECU, a pump to route the separated hydrogen from the gas separator to the storage tank.

In a non-limiting embodiment of the first aspect of present disclosure, a system for recovering hydrogen from a crankcase of a hydrogen internal combustion engine, is disclosed. The system includes a hydrogen sensor, associated with the crankcase, in which the hydrogen sensor is configured to generate signals corresponding to quantity of hydrogen in blow-by gases accumulated within the crankcase. The system further includes an electronic control unit [ECU], communicatively coupled to the hydrogen sensor. The ECU is configured to monitor quantity of hydrogen in the blow-by gases, based on signals received from the hydrogen sensor. The ECU is further configured to operate a valve coupled to a ventilation path of the crankcase, to selectively channelize and store the hydrogen in a storage tank, fluidly connected to the ventilation path.

In an embodiment of the present disclosure, the valve is operated to open condition by the ECU, when the quantity of hydrogen in the crankcase is more than a predefined limit.

In an embodiment of the present disclosure, the system includes a gas separator fluidly connected to the ventilation path. The gas separator is adapted to separate hydrogen from the blow-by gases.

In an embodiment of the present disclosure, the system includes a pump operatively coupled to the ECU, to route the separated hydrogen from the gas separator to the storage tank.

In an embodiment of the present disclosure, the storage tank is at least one of an auxiliary tank and a main tank associated with the hydrogen internal combustion engine

According to a second aspect of the present disclosure, a method for maintaining temperature of a catalyst chamber of an exhaust after treatment unit for a hydrogen internal combustion engine is disclosed. The method includes determining, by an electronic control unit [ECU], quantity of nitrogen oxides [NOx] in an exhaust gas from the hydrogen internal combustion engine, based on a signal received from a NOx sensor associated with the exhaust after treatment unit. The method further includes determining, by the ECU, temperature of the catalyst chamber based on signals from a temperature sensor associated with the exhaust after treatment unit, when the determined quantity of NOx in the exhaust gas exceeds a predefined value. The method further includes operating, by the ECU, a pump to inject hydrogen from a storage tank to a pre-ignition chamber, in which the injected hydrogen is combusted in the pre-ignition chamber to heat the exhaust gas, when the determined temperature of the catalyst chamber is less than a predefined limit.

In an embodiment of the present disclosure, the method includes operating by the ECU, a flow control valve coupled with the pre-ignition chamber, to direct combusted hydrogen to the catalyst chamber for maintaining temperature of the catalyst chamber above the predefined limit.

In an embodiment of the present disclosure, maintaining temperature of the catalyst chamber above the predefined limit increases rate of reaction between catalyst in the catalyst chamber and NOx in the exhaust gas.

In an embodiment of the present disclosure, the method includes triggering, by the ECU, an ignition element associated with the pre-ignition chamber, to selectively combust the hydrogen injected into the pre-ignition chamber.

In a non-limiting embodiment of the second aspect of present disclosure, a system for maintaining temperature of a catalyst chamber of an exhaust after treatment unit for a hydrogen internal combustion engine is disclosed. The system includes a NOx sensor associated with the exhaust after treatment unit, in which the NOx sensor is configured to generate a signal corresponding to quantity of NOx in an exhaust gas from the hydrogen internal combustion engine. The system further includes a temperature sensor associated with the exhaust after treatment unit, in which the temperature sensor is configured to generate signals corresponding to temperature of the catalyst chamber. The system further includes an electronic control unit [ECU], communicatively coupled to the NOx sensor and the temperature sensor. The ECU is configured to operate a pump to inject hydrogen from a storage tank to a pre-ignition chamber, in which the injected hydrogen is combusted in the pre-ignition chamber to heat the exhaust gas, when the determined temperature of the catalyst chamber is less than a predefined limit.

In an embodiment of the present disclosure, the system includes a flow control valve coupled with the pre-ignition chamber and in which the pre-ignition chamber is positioned upstream of the catalyst chamber.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Figure 1 illustrates schematic view of an overall system for recovering hydrogen from a crankcase of a hydrogen internal combustion engine and maintaining temperature of a catalyst chamber of an exhaust after treatment unit for the hydrogen internal combustion engine, in accordance with an embodiment of the present disclosure.

Figure 2 illustrates a schematic view of the system for recovering hydrogen from the crankcase of the hydrogen internal combustion engine, in accordance with an embodiment of the present disclosure.

Figure 3 is a flow chart illustrating sequence of steps involved in a method for recovering hydrogen from the crankcase of the hydrogen internal combustion engine, in accordance with an embodiment of the present disclosure.

Figure 4 illustrates a schematic view of the system for maintaining temperature of the catalyst chamber of the exhaust after treatment unit, in accordance with an embodiment of the present disclosure.

Figure 5 is a flow chart illustrating sequence of steps involved in a method for maintaining temperature of the catalyst chamber of the exhaust after treatment unit for the hydrogen internal combustion engine, in accordance with an embodiment of the present disclosure.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the system and the method illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

While the embodiments in the disclosure are subject to various modifications and alternative forms, specific embodiments thereof have been shown by the way of example in the figures and will be described below. It should be understood, however that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.

The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusions, such that a device, assembly, mechanism, system, method that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a system proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or method.

Embodiments of the present disclosure disclose a system and a method for recovering hydrogen from a crankcase of a hydrogen internal combustion engine. The method includes monitoring quantity of hydrogen in blow-by gases accumulated within the crankcase of the hydrogen internal combustion engine. The quantity of hydrogen in blow-by gases is monitored by an electronic control unit [ECU], based on signals received from a hydrogen sensor associated with the crankcase. The method further includes operating a valve coupled to a ventilation path of the crankcase. The valve is operated by the ECU, to selectively channelize and store the hydrogen in a storage tank fluidly connected to the ventilation path.

Further, in another non-limiting embodiment of the present disclosure, a system and a method for maintaining temperature of a catalyst chamber of an exhaust after treatment unit for the hydrogen internal combustion engine is disclosed. The method includes determining quantity of NOx in an exhaust gas emitted by the hydrogen internal combustion engine. The quantity of NOx in the exhaust gas is determined by the electronic control unit [ECU], based on a signal received from a NOx sensor associated with the exhaust after treatment unit. The method further includes determining temperature of the catalyst chamber by the ECU. The temperature of the catalyst chamber is determined based on signals from a temperature sensor associated with the exhaust after treatment unit. The ECU is configured to determine temperature of the catalyst chamber, when the determined quantity of NOx in the exhaust gas exceeds a predefined value. The method further includes operating a pump by the ECU, to inject hydrogen from a storage tank to a pre-ignition chamber. The injected hydrogen is combusted in the pre-ignition chamber and is mixed with the exhaust gas to heat the exhaust gas when the determined temperature of the catalyst chamber is less than a predefined limit.

The term ‘exhaust gas’ as used herein refers to burnt gases that may be produced as a by-product of combustion in the hydrogen internal combustion engine (referred to as ‘engine’ hereinafter). The exhaust gas may include, but may not be limited to, carbon dioxide, nitrogen oxides, water vapor and other gases in negligible proportion that may be produced due to elements and/or compounds in the air. Primarily, nitrogen oxides [or referred to as NOx] are produced as one of the by-products due to considerable amount of nitrogen gas in the air, which is being used for combustion along with hydrogen in the hydrogen internal combustion engine. Also, pre-set quantity of NOx allowable in the emission is dependent on regulatory norms of jurisdictions in which the hydrogen internal combustion engine may be operated. As such, operating parameters for regulating NOx may be dependent on various factors based on the jurisdictions.

The term ‘blow-by gas’ [or simply referred to as ‘blow-by’ as used herein] refers to gas that leaks from several sources in the hydrogen internal combustion engine, such as, but not limited to cylinders, cylinder liners, piston rings, piston ring clearance, turbochargers, air compressors, valve stems of the engine. The blow-by gas may include, but may not be limited to air, burned and unburned gases, traces of fuel and oil mist.

The term ‘ventilation path’ as used herein refers to a structural conduit extending from the crankcase of the engine to remove unwanted gases therefrom. The ‘ventilation path’ may include, but may not be limited to, at least one tube, a one-way valve and a vacuum source (such as a pressure manifold) for communication of gases from the crankcase. The ventilation channel may also be defined integrally with the crankcase of the engine, where such ventilation channel may extend from or into the crankcase to channelize the gases therein.

The term ‘exhaust after treatment unit’ as used herein refers to an assembly of the vehicle configured to treat exhaust gases emitted by the engine, for reducing harmful exhaust emissions, such as, but not limited to, nitrogen oxides, particulate matter and the like. The term ‘catalyst chamber’ as used herein refers to a space or an enclosure defined within the exhaust after treatment unit, in which the suitable catalysts known in the art may be positioned for physical and/or chemical reactions with the exhaust gases passing through the exhaust after treatment unit. Also, one skilled in the art would appreciate that, efficiency of the “catalyst chamber” may be elevated with increase in temperature of such space and/or enclosure defined therewith, in view of physical and/or chemical reactions produced therein.

In an embodiment, combustion in the hydrogen internal combustion engine may be between the hydrogen injected as fuel and oxygen in the air being supplied, while other constituent gases in the air may also undergo sub-combustion due to energy and thermal elevation produced therefrom.

The disclosure is described in the following paragraphs with reference to Figures 1 to 5. In the figures, the same element or elements which have same functions are indicated by the same reference signs. It is to be noted that, the vehicle and the hydrogen internal combustion engine are not illustrated in the figures for the purpose of simplicity. One skilled in the art would appreciate that the systems and the methods as disclosed in the present disclosure may be used in any vehicles that is capable of being driven by the hydrogen internal combustion engine, where such vehicle may include, but not be limited to, light vehicles, passenger vehicles, commercial vehicles, and the like.

Figure 1 is an exemplary embodiment of the present disclosure, illustrating a system for recovering hydrogen from a crankcase of a hydrogen internal combustion engine, and utilizing such recovered hydrogen for maintaining temperature of a catalyst chamber of an exhaust after treatment unit associated with the hydrogen internal combustion engine. Further, while Figure 2 illustrates a schematic view of the system for recovering hydrogen from the crankcase of the hydrogen internal combustion engine, Figure 4 illustrates a schematic view of the system for maintaining temperature of the catalyst chamber of the exhaust after treatment unit. Accordingly, the system as illustrated in Figure 1 is a combination/incorporation of the systems as illustrated in Figures 2 and 4. Hence, a person skilled in the art would appreciate that the system, as illustrated in Figure 1, may be employed in hydrogen internal combustion engines, to recover hydrogen from blow-by gases and to utilize such recovered hydrogen for maintaining temperature of the catalyst chamber of the exhaust after treatment unit associated with the hydrogen internal combustion engine.

Figures 1 and 2 are exemplary embodiments of the present disclosure which illustrate a system (100, 200) for recovering hydrogen from a crankcase (3) of a hydrogen internal combustion engine (1). The system (100, 200) may include a hydrogen injector, configured to inject a determined quantity of hydrogen to each cylinder (2) of the engine (1). The engine (1) may be configured to receive hydrogen in a gaseous form from the hydrogen injector, where the hydrogen is configured to act as a fuel for operation of the engine (1). The hydrogen injector may be operatively coupled to an ECU (5), and the ECU (5) may be configured to control a quantity of hydrogen being injected into each cylinder (2) of the engine (1). In an embodiment, the hydrogen may be supplied from a hydrogen source (17) including, but not limited to, a hydrogen fuel cell, a hydrogen tank, and any other source capable of generating or storing hydrogen for selectively supplying to the engine (1) via the hydrogen injector. The engine (1) includes various components such as, but not limited to, cylinder, cylinder head, piston disposable in the cylinder, and a crankcase positioned downstream of the cylinder. The crankcase (3) provides an enclosed volume for operational movement of pistons, connecting rods and crankshaft of the engine (1). The enclosed volume of the crankcase (3) is usually vented for controlling air displacement caused by reciprocating pistons and other moving parts of the engine (1).

The system (100, 200) includes a hydrogen sensor (13) configured to generate signals corresponding to quantity of hydrogen in blow-by gases accumulated within the crankcase (3). The hydrogen sensor (13) may be mounted on the crankcase (3) of the engine (1) such that, signals generated by the hydrogen sensor (13) indicate quantity of hydrogen in the blow-by gases accumulated within the crankcase (3). The hydrogen sensor (13) may be externally coupled to the crankcase (3) by means including, but not limited to, mechanical or thermal joining methods. In an embodiment, the hydrogen sensor (13) may also be configured to indicate pressure within the crankcase (3) of the engine (1). The hydrogen sensor (13) may be configured to generate signals continuously and in real time, to enable constant monitoring of the quantity of hydrogen in the crankcase (3). Also, it should be noted that the hydrogen sensor (3) may be configured to selectively and periodically generate the signals, based on pre-set functioning of such hydrogen sensor (3). The hydrogen sensor (3) may be configured to detect quantity of hydrogen in the crankcase (3) by means including, but not limited to, chemical reactions, physical deposition or adsorption, optical interference, magnetic reaction, and the like, based on nature of sensory element being employed therein.

Further, as detailed in Figures 1 and 2, the system (100, 200) also includes the electronic control unit [ECU] (5), communicatively coupled to the hydrogen sensor (13). The ECU (5) may be configured to monitor quantity of hydrogen in the blow-by gases, based on signals received from the hydrogen sensor (13). The ECU (5) may be further configured to operate a valve (11) coupled to a ventilation path (24) of the crankcase (3). The valve (11) is operated to an open condition based on an operational signal from the ECU (5), when the quantity of hydrogen in the crankcase (3) is more than a predefined limit. In an exemplary embodiment, the predefined limit may be at least 1% of hydrogen per volume of the crankcase (3). The predefined limit may be based on at least one of the enclosed volume of the crankcase (3), substantially atmospheric pressure surrounding the crankcase (3), volumetric quantity of the hydrogen in the crankcase (3), pressure inside the crankcase (3), material characteristics of the crankcase (3), operating condition of the engine, and other parameters affecting volumetric capacity of the crankcase (3). By operating the valve (11) to the open condition, the blow-by gases including the hydrogen that may be accumulated in the crankcase (3), may be selectively channelized and stored in a storage tank (22). In the embodiment, the storage tank (22) may be fluidly connected to the ventilation path (24) of the crankcase (3). In an embodiment, the valve (11) may be a solenoid valve, a piezoelectric valve, a pneumatic valve, a hydraulic valve and any other valve that may be operable between an open condition and a closed condition on receiving the operational signal from the ECU (5), for channelizing fluid in one-direction. The ECU (5) may be configured to operate the valve (11) to the open condition, when the quantity of hydrogen in the crankcase (3) exceeds the predefined limit. However, the ECU (5) may also be configured to operate the valve (11) to the open condition, when pressure inside the crankcase (3) exceeds a predefined limit and/or when the pressure inside the crankcase (3), caused by the accumulation of blow-by gases, affects normal operation and operational efficiency of the engine (1). With such configuration, the ECU (5) may be configured to selectively operate the valve (11) based on signals from the hydrogen sensor (13), whereby recovering hydrogen from the crankcase (3) of the engine (1).

In an embodiment, the ventilation path (24) may be structured to channelize the blow-by gases through a gas separator (7), to separate hydrogen from the blow-by gases. The gas separator (7) may be positioned downstream of the valve (11) in the ventilation path (24) and may be configured to separate hydrogen from other constituent gases in the blow-by gas. In the embodiment, the gas separator (7) may include one or more filter materials to selectively bifurcate constituents of the blow-by gas. For example, the filter material may be including, but not limited to, micro-channel palladium alloy membranes, to separate hydrogen from the blow-by gases. The gas separator (7) may also be a sulfur-tolerant palladium alloy, for separation of hydrogen from blow-by gases containing sulfur compounds. In addition, a sweep gas, such as nitrogen or steam, may be selectively suppled to the gas separator (7), in order to increase rate at which hydrogen may be recovered from the blow-by gas. Subsequent to recovery of hydrogen from the blow-by gas, remaining constituent gases in the blow-by gas may continue through the gas separator (7) and may suitably be discharged to atmosphere (19) through exhaust after treatment unit (4).

In an embodiment, the system (100, 200) may further include a pump (12), operatively coupled to the ECU (5), to route the separated hydrogen from the gas separator (7) to the storage tank (22). The pump (12) may be fluidly connected between the gas separator (7) and the storage tank (22), to selectively channelize the separated hydrogen from the gas separator (7) to the storage tank (22), based on operational signal received from the ECU (5). In the embodiment, the pump (12) may be a positive displacement pump, which may be based on factors including, but not limited to, configuration in which power is supplied to the pump (12) [that is, either mechanical and/or electrical], and nature of power being supplied [that is, either electrical power or mechanical power], and the like.

In the illustrative embodiment, as detailed in Figure 2, the storage tank (22) may be positioned downstream of the pump (12). The storage tank (22) may be at least one of an auxiliary tank (8) and a main tank (9) associated with the engine (1). In the embodiment, the auxiliary tank (8) and the main tank (9) may be positioned downstream of the pump (12) and may be arranged in series thereof. A valve (21) may be fluidly connected and positioned between the auxiliary tank (8) and the main tank (9). The valve (21) may be operated by the ECU (5) and may be configured to regulate flow of separated hydrogen from the auxiliary tank (8) to the main tank (9). In the embodiment, the valve (21) may be a solenoid valve, a piezoelectric valve, and any other valve that may be operable between an open condition and a closed condition on receiving the operational signal from the ECU (5). In the embodiment, the ECU (5) may be configured to operate the valve (21) to the open condition, when the quantity of hydrogen in the auxiliary tank (8) exceeds the predefined limit. However, the ECU (5) may also be configured to operate the valve (21) to the open condition, when pressure inside the auxiliary tank (8) exceeds a predefined limit. In the embodiment, the separated hydrogen, that may be stored in the auxiliary tank (8) and the main tank (9), may be routed to the engine (1) to act as fuel for operation of the engine (1).

Referring now to Figure 3 which is an exemplary embodiment of the present disclosure illustrating a flow chart of a method (400) for recovering hydrogen from a crankcase (3) of the hydrogen internal combustion engine (1). In an embodiment, the method (400) may be implemented in any vehicle including, but not limited to, passenger vehicles, commercial vehicles, hovers, and the like, which may be operable by hydrogen internal combustion engine (1).

The method (400) may describe in the general context of processor executable instructions. Generally, the executable instructions may include routines, programs, objects, components, data structures, procedures, modules, and functions, which perform particular functions or implement particular abstract data types.

The order in which the method (400) is described is not intended to be construed as a limitation, and any number of the described method blocks may be combined in any order to implement the method (400). Additionally, individual blocks may be deleted from the method (400) without departing from the scope of the subject matter described herein. Furthermore, the method (400) can be implemented in any suitable hardware, software, firmware, or combination thereof.

As depicted at block 401, the method (400) includes monitoring, by an electronic control unit [ECU] (5), quantity of hydrogen in blow-by gases accumulated within the crankcase (3) of the hydrogen internal combustion engine (1). The quantity of hydrogen is monitored based on signals received from the hydrogen sensor (13) associated with the crankcase (3).

As depicted at block 402, the method (400) includes operating, by the ECU (5), a valve (11) coupled to the ventilation path (24) of the crankcase (3). The valve (11) is operated to selectively channelize and store the hydrogen in a storage tank (22), fluidly connected to the ventilation path (24). With such configuration, the ECU (5) may be configured to selectively operate the valve (11) based on signals from the hydrogen sensor (13), whereby recovering hydrogen from the crankcase (3) of the engine (1).

In an embodiment, the valve (11) may be operated to open condition by the ECU (5), when the quantity of hydrogen in the crankcase (3) is more than a predefined limit. In the embodiment, the ventilation path (24) may be structured to channelize the blow-by gases through the gas separator (7) to separate hydrogen from the blow-by gases. In the embodiment, the method (400) may further include operating the pump (12) by the ECU (5) to route the separated hydrogen from the gas separator (7) to the storage tank (22). The storage tank (22) may be at least one of an auxiliary tank (8) and a main tank (9) associated with the hydrogen internal combustion engine (1).

In an embodiment, the method (400) and the system (100, 200) is configured to recover hydrogen from blow-by gases accumulated in the crankcase (3) of the engine (1). Such recovery of hydrogen from blow-by gases, and then by supplying the recovered hydrogen to the auxiliary tank (8) and the main tank (9) of the engine (1), reduces need for additional supply of hydrogen, for compensating loss of hydrogen caused by blow-by.

Now referring to Figure 4 in conjunction with Figure 1, which illustrate a system (100, 300) for maintaining temperature of a catalyst chamber (23) of an exhaust after treatment unit (4) for the hydrogen internal combustion engine (1). The system (100, 300) includes a NOx sensor (16) associated with the exhaust after treatment unit (4) and may be configured to determine NOx emissions in the exhaust gas treated by the exhaust after treatment unit (4). The system (100, 300) may include an exhaust manifold (18) configured to route exhaust gas to the exhaust after treatment unit (4), and subsequently to be discharged to atmosphere (19). It may also be inherent that, by increasing number of NOx sensors (16), the quantity of NOx emissions in the exhaust gas at various positions may be determined, which should be construed within operation of the system (100, 300). The NOx sensor (16) may be configured to generate a signal corresponding to quantity of NOx in the treated exhaust gas. The exhaust after treatment unit (4) may include a catalyst chamber (23) including a catalytic convertor and/or reductant injector unit, configured to reduce and/or regulate quantity of NOx emissions in the exhaust gas.

In an embodiment, the NOx sensor (16) may an yttria stabilized zirconia (YSZ) electrochemical sensor of amperometric type. In the embodiment, the NOx sensor (16) may include a ceramic sensor element that operates according to amperometric double chamber principle, for detecting quantity of NOx in the treated exhaust gas.

The system (100, 300) further includes a temperature sensor (14) to determine temperature of the catalyst chamber (23) of the exhaust after treatment unit (4). The temperature sensor (14) may be associated with the exhaust after treatment unit (4) and may be configured to generate signals corresponding to temperature of the catalyst chamber (23). Temperature of the catalyst chamber (23) influences reduction and regulation of quantity of NOx emissions in the exhaust gas. To maintain an optimum reduction performance of the exhaust after treatment unit (4) and to meet regulatory norms relating to quantity of NOx allowable in the emission, it is essential that the temperature of the catalyst chamber (23) is maintained within a predefined range or above a predefined limit. In an exemplary embodiment, the predefined range of the temperature of the catalyst chamber (23) may be about 150 °C to about 600 °C, in accordance with quantity of NOx required to be treated for a defined load being operated by the engine (1). The predefined range of the temperature of the catalyst chamber (23) may be based on chemical compounds involved in catalyst coating, type of catalyst coating employed in the catalyst chamber (23), operating temperature range of the engine (1), load carrying capacity of the engine (1), allowable NOx limit as per location in which the engine (1) is operated and any other parameters affecting operation of the exhaust after treatment unit (4). By maintaining temperature of the catalyst chamber (23) above the predefined limit, rate of reaction between catalyst in the catalyst chamber (23) and NOx in the exhaust gas, may be increased. Both the NOx sensor (16) and the temperature sensor (14) may be disposed within the exhaust after treatment unit (4). The temperature sensor (14) may be positioned upstream of the NOx sensor (16).

In an embodiment, the temperature sensor (14) may be including, but not limited to, thermocouples, resistive temperature devices (RTDs, thermistors), infrared radiators, bimetallic devices, liquid expansion devices, molecular change-of-state and silicon diodes, that may be configured to determine temperature of the catalyst chamber (23) of the exhaust after treatment unit (4).

The NOx sensor (16) and the temperature sensor (14) may be communicatively coupled to the electronic control unit [ECU] (5). The ECU (5) may be configured to operate a pump (20) to inject hydrogen from the storage tank (22) to a pre-ignition chamber (6). The injected hydrogen is combusted in the pre-ignition chamber (6) to heat the exhaust gas, when the determined temperature of the catalyst chamber (23) is less than a predefined limit. The pump (20) may be fluidly connected to the storage tank (22) and may be positioned upstream of the pre-ignition chamber (6). The storage tank (22) may be at least one of an auxiliary tank (8) and a main tank (9) associated with the engine (1). The pre-ignition chamber (6) may be positioned upstream of the catalyst chamber (23). The pump (20) may be operated by the ECU (5), to channelize hydrogen in the storage tank (22) to the pre-ignition chamber (6). In the embodiment, the pump (20) may be a positive displacement pump, which may be based on factors including, but not limited to, configuration in which power is supplied to the pump (20) [that is, either mechanical and/or electrical], and nature of power being supplied [that is, either electrical power or mechanical power], and the like. In the embodiment, the system (100, 300) may include a gas controller (10) that may be associated with the pump (20) and the storage tank (22). The gas controller (10) may be operatively coupled to the ECU (5). The ECU (5) may be configured to operate the gas controller (10), to regulate hydrogen injection to the pre-ignition chamber (6) from the storage tank (22). In an embodiment, the gas controller (10) may be a part of the ECU (5). However, the gas controller (10) may also be separate from the ECU (5) and may be operatively coupled to the ECU (5).

In the illustrative embodiment, the system (100, 300) may include a flow control valve (15) that may be coupled to the pre-ignition chamber (6). The pre-ignition chamber (6) may include an ignition element (not shown in figures) operatively coupled to the ECU (5). The ECU (5) may be configured to trigger the ignition element associated with the pre-ignition chamber (6), to selectively combust hydrogen injected into the pre-ignition chamber (6). The flow control valve (15) may be operated by the ECU (5), to direct combusted hydrogen to the catalyst chamber (23) for maintaining temperature of the catalyst chamber (23) above the predefined limit. In an embodiment, the flow control valve (15) may be a solenoid valve, a piezoelectric valve, flap valve, and any other valve that may be operable between an open condition and a closed condition on receiving the operational signal from the ECU (5). In the embodiment, the ECU (5) may be configured to operate the flow control valve (15) to the open condition, when the temperature of the catalyst chamber (23) falls below the predefined limit. In addition, the ECU (5) may be configured to operate the flow control valve (15) to the open condition, only after the combusted hydrogen in the pre-ignition chamber (6) attains a particular temperature and/or pressure value. With such configuration, the ECU (5) may be configured to selectively operate the flow control valve (15) based on signals from the NOx sensor (16) and the temperature sensor (14), whereby maintaining temperature of the catalyst chamber (23) above the predefined limit.

In an embodiment, the ECU (5) may be a centralized control unit of the vehicle or may be a dedicated control unit to the system (100, 200, 300) associated with the centralized control unit of the vehicle. The ECU (5) may also be associated with other control units including, but not limited to, body control unit, engine control unit, and the like. The ECU (5) may be comprised of a processing unit. The processing unit may comprise at least one data processor for executing program components for executing user- or system generated requests. The processing unit may be a specialized processing unit such as integrated system (bus) controllers, memory management control units, floating point units, graphics processing units, digital signal processing units, etc. The processing unit may include a microprocessor, such as AMD Athlon, Duron or Opteron, ARM’s application, embedded or secure processors, IBM PowerPC, Intel’s Core, Itanium, Xeon, Celeron, or other line of processors, etc. The processing unit may be implemented using a mainframe, distributed processor, multi-core, parallel, grid, or other architectures. Some embodiments may utilize embedded technologies like application-specific integrated circuits (ASICs), digital signal processors (DSPs), Field Programmable Gate Arrays (FPGAs), etc.

The ECU (5) may be disposed in communication with one or more memory devices (e.g., RAM, ROM etc.) via a storage interface. The storage interface may connect to memory devices including, without limitation, memory drives, removable disc drives, etc., employing connection protocols such as serial advanced technology attachment (SATA), integrated drive electronics (IDE), IEEE-1394, universal serial bus (USB), fiber channel, small computing system interface (SCSI), etc. The memory drives may further include a drum, magnetic disc drive, magneto-optical drive, optical drive, redundant array of independent discs (RAID), solid-state memory devices, solid-state drives, etc.

Referring now to Figure 5 which is an exemplary embodiment of the present disclosure illustrating a flow chart of a method (500) for maintaining temperature of a catalyst chamber (23) of an exhaust after treatment unit (4) for the hydrogen internal combustion engine (1). In an embodiment, the method (500) may be implemented in any vehicle including, but not limited to, motorcycles, cars, trucks, gliders, hovers, and the like, which may be operable by hydrogen internal combustion engine (1).

The method (500) may describe in the general context of processor executable instructions. Generally, the executable instructions may include routines, programs, objects, components, data structures, procedures, modules, and functions, which perform particular functions or implement particular abstract data types.

The order in which the method (500) is described is not intended to be construed as a limitation, and any number of the described method blocks may be combined in any order to implement the method (500). Additionally, individual blocks may be deleted from the method (500) without departing from the scope of the subject matter described herein. Furthermore, the method (500) can be implemented in any suitable hardware, software, firmware, or combination thereof.

As depicted at block 501, the method (500) includes determining, by the electronic control unit [ECU] (5), quantity of NOx in the exhaust gas from the hydrogen internal combustion engine (1). The quantity of NOx in the exhaust gas is determined based on a signal received from the NOx sensor (16) associated with the exhaust after treatment unit (4).

As depicted at block 502, the method (500) includes determining, by the ECU (5), temperature of the catalyst chamber (23) of the exhaust after treatment unit (4). Temperature of the catalyst chamber (23) may be determined based on signals from the temperature sensor (14) associated with the exhaust after treatment unit (4). The temperature of the catalyst chamber (23) may be determined when the determined quantity of NOx in the exhaust gas exceeds a predefined value.

As depicted at block 503, the method (500) includes operating, by the ECU (5), a pump (20) to inject hydrogen from a storage tank (22) to a pre-ignition chamber (6). The injected hydrogen is combusted in the pre-ignition chamber (6) to heat the exhaust gas. The combusted hydrogen is mixed with the exhaust gas, when the determined temperature of the catalyst chamber (23) is less than a predefined limit.

In an embodiment, the method (500) includes operating by the ECU (5), the flow control valve (15) associated with the pre-ignition chamber (6). The flow control valve (15) may be operated to direct combusted hydrogen to the catalyst chamber (23), for maintaining temperature of the catalyst chamber (23) above the predefined limit. By maintaining temperature of the catalyst chamber (23) above the predefined limit, rate of reaction between catalyst in the catalyst chamber (23) and NOx in the exhaust gas is increased. In the embodiment, the method (500) includes operating the pump (20) by the ECU (5) to the pre-ignition chamber (6) from the storage tank (22). Further, the method (500) includes triggering, by the ECU (5), an ignition element associated with the pre-ignition chamber (6). The ignition element (500) may be triggered to selectively combust the hydrogen injected into the pre-ignition chamber (6). With such configuration, the ECU (5) may be configured to selectively operate the flow control valve (15) based on signals from the NOx sensor (16) and the temperature sensor (14), whereby maintaining temperature of the catalyst chamber (23) above the predefined limit.

In an embodiment, the method (500) and the system (100, 400) enable utilization of the recovered hydrogen to heat the exhaust gas. The heated exhaust gas maintains temperature of the catalyst chamber (23) above a predefined limit. By maintaining the temperature of the catalyst chamber (23) above the predefined limit, NOx emissions from the engine (1) may be regulated, without having to compromise on load capacity, and durability of such hydrogen internal combustion engine (1). Further, such configuration of the methods (400, 500) and system (100, 200, 300) reduces operational costs associated with the hydrogen internal combustion engine (1).

EQUIVALENTS

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system (100) having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system (100) having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

REFERRAL NUMERICALS
Particulars Numerical
System 100, 200, 300
System for recovering hydrogen from a crankcase of a hydrogen internal combustion engine 200
System for maintaining temperature of a catalyst chamber of an exhaust after treatment unit for the hydrogen internal combustion engine 300
Engine 1
Cylinders 2
Crankcase
3
Exhaust after treatment unit 4
Electronic Control Unit (ECU) 5
Pre-ignition chamber 6
Gas separator 7
Auxiliary tank 8
Main tank 9
Gas Controller 10
Valve
11
Pump 12
Hydrogen sensor 13
Temperature sensor 14
Flow control valve 15
NOx sensor 16
Intake 17
Exhaust manifold 18
Atmosphere 19
Pump 20
Valve 21
Storage tank 22
Catalyst chamber 23
Ventilation path 24
Method for recovering hydrogen from a crankcase of a hydrogen internal combustion engine 400
Steps included in method 400 401-402
Method for maintaining temperature of a catalyst chamber of an exhaust treatment unit 500

Steps included in method 500 501-503