KR20170124450A - An internal combustion engine with fuel gas property measurement system - Google Patents

Abstract

The present invention relates to an internal combustion engine including one or more cylinders (1), a combustion cell (40), and a fuel gas supply system (30) configured to supply a flow of fuel gas to the cylinder (1) at a given pressure and temperature and to supply a flow of fuel gas to a combustion cell (40) at a given pressure and temperature. At least one gas inlet valve (31) is provided in each of the one or more cylinders (1), and a nozzle (30) is provided in the combustion cell (40) for injecting the flow of fuel gas from the fuel gas supply system (1) to the combustion cell (40). The internal combustion engine further includes: a supply line (42) for supplying a flow of oxidizing gas to the combustion cell (40); an exhaust conduit (47) for transferring the flow of the combustion gas from the combustion cell (40); and a sensor for measuring an oxygen ratio in the combustion gas flow.

Description

TECHNICAL FIELD [0001] The present invention relates to an internal combustion engine equipped with a fuel gas characteristic measuring system,

       The present disclosure relates to an internal combustion engine that is operated with fuel gas.

      An internal combustion engine such as a two-stroke engine and a four-stroke engine using the Otto principle or the diesel principle can be operated as a liquid fuel or a gaseous fuel. For proper operation of a modern engine, you must know the exact load of the engine. The engine load information includes the injection timing (and exhaust valve opening timing) and length, variable turbocharger setting, SCR setting, EGR setting, injection gas pressure, hydraulic system pressure, exhaust gas bypass opening, cooling fan speed, And so on. The previous example is not exhaustive and depends on the engine type. In any case, all internal combustion engines have a commonality that they must accurately measure the engine load for proper operation.

      In the prior art it is known to measure the torque and rotational speed of the crankshaft and derive the engine load from this information. It is also known to measure the amount of fuel consumed to determine the load. However, this requires that the characteristics of the fuel, in particular the exothermic character and density, are known or can be determined precisely. In the case of gaseous fuels, it is more difficult to measure the density of the delivered fuel due to changes in pressure and temperature, and it is also generally more difficult to determine the exothermic characteristics due to the compositional change of the gas delivered to the combustion chamber of the engine.

      One way to determine the characteristics of gaseous fuels is to use a gas chromatograph to collect samples at regular intervals. By analyzing the gas composition, the necessary information about the characteristics of the gas can be assessed. However, taking samples over time using gas chromatographs, for example, is costly, time-consuming, and does not provide immediate results, so the engine always works with outdated information (usually at least a few minutes past). Delayed emissions of measured results relative to actual gas sampling reduce the accuracy of engine operation.

Other instruments available measure or output the standard wobble index. The Weber index is an indicator of fuel gas compatibility. The Weber's index I _W is defined as: I _W = V _C / (square root G _S ), where V _C is the higher calorific value and G _S is the specific gravity.

      The Weber index is used to compare the combustion energy output of different composition fuel gases of the device. If the two fuel weber indices are the same, the energy output for the given pressure and valve setting will be the same.

       However, the Weber index is not the information needed to accurately determine the engine load because it only provides a comparison of gas quality / characteristics.

       Therefore, in order to improve the control of the internal combustion engine operated by the fuel gas, it is necessary to accurately determine the characteristics and the state of the fuel gas delivered to the engine without a large delay.

       JP2005226621 discloses an internal combustion engine according to the premise of claim 1. [ JP2005226621 discloses a first gas-operated internal combustion engine with a device for determining the characteristics of the gas supplied to the engine. One or more other internal combustion engine is operated with the same gas supply from the same source as the first gas operated internal combustion engine. The setting of the first engine is based on its own device and the setting is used for other engines to operate properly with respect to the gas supply. Thus, only one single engine is provided, and other engines can operate without the device using the information from the first engine. However, this does not provide a solution for situations where there is only one gas-operated engine, that is, for ships that usually use large two-stroke diesel engines.

      In view of this background, an object of the present invention is to provide a system for overcoming or at least reducing the above-mentioned problems.

      The above and other objects are achieved by the features of the independent claim. Additional implementations are evident from the dependent claims and the detailed description and drawings.

      According to a first aspect of the present invention there is provided a fuel cell system comprising at least one cylinder, a combustion cell, and a fuel cell configured to supply a flow of fuel gas to a cylinder at a given pressure and temperature and to supply a flow of fuel gas to the combustion cell at a given pressure and temperature A fuel cell system comprising: a fuel gas supply system, at least one cylinder each having at least one fuel inlet valve, a combustion cell having a nozzle for injecting a flow of fuel gas into the combustion cell from the fuel gas supply system, An exhaust conduit for transferring the flow of the combustion gas from the combustion cell, and a sensor device for measuring the oxygen ratio in the combustion gas flow.

      A direct measurement of the energy or value indicative of the exothermic characteristic of the fuel gas injected through the nozzle of the combustion cell can be determined in accordance with precisely the same conditions as those applied to the fuel gas supplied to the fuel inlet valve of the internal combustion engine. This information can be used directly in engine control without further correction taking into account the fuel gas temperature and pressure or other corrections. Whereby the range of gas qualities acceptable to the internal combustion engine can be greatly increased. The system can be integrated directly into the internal combustion engine itself or the gas valve train (gas supply system).

       In a first embodiment of the first aspect, the engine comprises an apparatus for maintaining a constant oxygen mass ratio in the flow of oxidant gas.

       In a second embodiment of the first aspect, the engine comprises an apparatus for controlling an oxygen mass ratio in a flow of oxidant gas.

       In a third embodiment of the first aspect, the engine comprises an apparatus for measuring the flow rate of the oxidant gas fed to the combustion cell or the ratio of the oxygen mass in the oxidant gas flow fed to the combustion cell.

       In a fourth embodiment of the first aspect, the engine includes a control device for receiving a signal from an apparatus for delivering an oxygen mass ratio in the oxidant gas flow to the combustion cell and for measuring the oxygen ratio in the combustion gas flow.

       In a fifth embodiment of the first aspect, the engine is configured to inject, via a nozzle, a signal based on a signal from an apparatus for measuring an oxygen mass ratio in an oxidant gas flow and a signal from an apparatus for measuring an oxygen ratio in a combustion gas flow, And a control device configured to determine the energy to be applied.

       In a sixth embodiment of the first aspect, the control device is configured to determine a value indicative of the calorific value of the fuel gas supplied to the cylinder and the combustion cell.

       In a seventh embodiment of the first aspect, the engine takes into account the amount of energy injected through the nozzle or a value representative of the calorific value of the fuel gas supplied to the cylinder and the combustion cell, via one or more cylinders And a control device configured to measure the energy injected or injected.

       In an eighth embodiment of the first aspect, the control device is configured to determine the engine load from the amount of energy injected or injected into the one or more cylinders via the fuel inlet valve.

       In a ninth embodiment of the first aspect, the control device is informed of the relationship between the nozzle size and the fuel inlet valve size.

       In a tenth embodiment of the first aspect, the control device receives the correct size of the nozzle and the correct size of the fuel inlet valve.

       In an eleventh embodiment of the first aspect, the control device is configured to use a value indicating a calorific value of the fuel gas supplied to the cylinder and the combustion cell as a correction coefficient for calculating an engine load.

        In a twelfth embodiment of the first aspect, the oxidant gas is air.

       In a thirteenth embodiment of the first aspect, the oxidant gas is a mixture of nitrogen and air.

        In a fourteenth embodiment of the first aspect, the oxygen content of the oxidant gas is lower than the oxygen content of the surrounding air.

         In a fifteenth embodiment of the first aspect, the combustion cell is provided with an oxidation catalyst.

         In a sixteenth embodiment of the first aspect, the combustion cell is provided with a cooling system.

        In a seventeenth embodiment of the first aspect, the apparatus for determining an oxygen ratio in a combustion gas flow comprises a lambda sensor.

        In an eighteenth embodiment of the first aspect, the control device is configured to control the oxygen mass ratio or the flow rate of the oxidant gas in response to a signal from an apparatus for determining the oxygen ratio in the combustion gas.

        In a nineteenth embodiment of the first aspect, the flow rate of the fuel gas flow to the combustion cell is less than the flow rate of the fuel gas flow to the one or more cylinders.

        In a twentieth embodiment of the first aspect, the control device is configured to determine the amount of oxygen consumed during combustion of the combustion cell.

        In a twenty-first embodiment of the first aspect, the combustion cell is calibrated using a known gas, preferably pure gas, such as pure methane. That is, the nozzle size is determined using pure gas. The required oxygen consumption is determined for the combustion cell 40 by a known gas, and all other gases process the deviation based on that case.

        In a twenty-second embodiment of the first aspect, the combustion cell is not a combustion chamber of an internal combustion engine.

        In a twenty-third embodiment of the first aspect, the combustion cell includes a combustion chamber configured to combust both a fuel gas and an oxidant gas that are supplied at a substantially constant flow rate and are combusted in a continuous process.

        According to a second aspect of the present invention, there is provided a method for determining a characteristic of a fuel gas in an internal combustion engine operated with fuel gas, the method comprising:

        Supplying a fuel gas to a cylinder of the engine at a given pressure and temperature and supplying a flow of fuel gas to the combustion cell at the same given pressure and temperature, supplying a flow of oxidant gas to the combustion cell, Generating a flow of the combustion gas by burning the fuel gas together, and measuring the oxygen ratio in the combustion gas.

         In a first embodiment of the second aspect, the method further comprises determining or controlling the oxygen mass fraction in the oxidant gas flow, preferably corresponding to the ratio of oxygen measured in the combustion gas.

         In a second embodiment of the second aspect, the method further comprises the step of determining a value indicative of the exothermic character of the fuel gas.

         In a third embodiment of the second aspect, the method further comprises determining an engine load based on a time at which the fuel inlet valve of the engine is open and a value indicative of a heating characteristic of the fuel gas.

          In a fourth embodiment of the second aspect, the method further comprises determining the amount of oxygen consumed during combustion of the combustion cell.

         These and other aspects of the invention will become apparent from the embodiments described below.

According to the present invention, there is an effect of providing a system that overcomes or at least reduces the above-mentioned problems.

BRIEF DESCRIPTION OF THE DRAWINGS In the following detailed description of the invention, the invention is explained in more detail with reference to the embodiments shown in the drawings.
1 is a front elevational view of a large two-stroke diesel engine according to an embodiment of the present invention.
Fig. 2 is a side elevational view of the large two-stroke engine of Fig. 1; Fig.
Figure 3 is a schematic representation of a large two-stroke engine according to Figure 1;
4 is a schematic representation of a system for measuring the characteristics of the fuel gas supplied to the cylinder of the engine.
5 is a flow chart illustrating a method of measuring a characteristic of a fuel gas to a cylinder of an engine.

       In the following detailed description, the internal combustion engine will be described with reference to a large two stroke, low speed turbocharged compression ignition internal combustion engine including a crosshead in the exemplary embodiments, but the internal combustion engine may be a two stroke stroke, four stroke stroke, And it should be understood that turbocharging and exhaust gas recirculation may or may not be present.

        Figures 1, 2 and 3 illustrate a large low speed turbocharged two stroke compression ignition engine with a crankshaft 8 and a crosshead 9. Figure 3 shows a schematic representation of a large low speed turbocharged two stroke diesel engine with intake and exhaust systems. In this embodiment, the engine has six cylinders in a row. A large low speed turbocharged two stroke diesel engine is supported by a cylinder frame 23 supported by an engine frame 11 and typically has four to fourteen cylinders in heat. The engine can be used, for example, as a main engine of a ship or as a stationary engine that operates a generator of a power plant. The total output of the engine may range, for example, from 1,000 to 110,000 kW.

      In this embodiment, the engine is provided with a two-stroke unflow compression ignition engine 1 having a scavenge port 18 in the lower region of the cylinder liner 1 and an exhaust valve 4 at the center of the cylinder liner 1, to be. The scavenge passes from the scavenging receptacle 2 to the scavenging port 18 of the individual cylinder 1. The piston 10 in the cylinder 1 compresses the aspiration and the fuel is injected through the fuel injection valve 31 of the cylinder cover 22 so that combustion progresses and exhaust gas is generated.

        When the exhaust valve 4 is opened, the exhaust gas flows to the exhaust gas receiving portion 3 through the exhaust duct coupled with the cylinder 1, and then flows through the first exhaust conduit 19 to the turbocharger 5, The exhaust gas is discharged through the second exhaust conduit 7 via the economizer 20 to the outlet 21 and into the atmosphere. The turbine (6) drives the compressor (7) through fresh air through the intake port (12) through the shaft. The compressor (7) transfers the pressurized scoop to the scraper conduit (13) leading to the scoop storage portion (2). The scavenging in conduit 13 passes through intercooler 14 for expected cooling.

       If the compressor 7 of the turbocharger 5 does not deliver sufficient pressure to the scavenging receiver 2, that is, under a low load or partial load condition of the engine, the scavenged scavenged electric motor 17 Through an auxiliary blower 16 which is driven by a blower (not shown). At higher engine loads, the turbocharger compressor 7 delivers sufficiently compressed air and then the auxiliary blower 16 is bypassed via the check valve 15.

       The engine is operated by a fuel gas, such as natural gas, coal gas, biogas, landfill gas, methane, ethylene, LPG, and is supplied by a gas supply system 30 in the form of a gas at a generally stable pressure and temperature. However, depending on the details of the gas supply system and the type of gas supplied, a slight change in temperature and pressure is inevitable. Also, slight changes in the composition of the gaseous fuel may occur.

       The gas supply system supplies gaseous fuel under pressure to all the fuel injection valves 31. The electronic control unit 60 of the engine receives signals from various sensors via a signal line shown by a broken line in Fig. Signals from various sensors include, for example, charge pressure and temperature, exhaust pressure and temperature, crank angle and speed, but this list is not exhaustive and may include engine configurations such as whether to include exhaust gas recirculation and turbochargers It should be noted that it depends on. The electronic control unit 60 controls the fuel injection valve 31. [ That is, the electronic control apparatus determines when the fuel injection valve 31 is opened and determines the length of the opening time. The opening time of the fuel valve has a great influence on the combustion pressure of the diesel engine (compression ignition engine), and the open duration of the fuel valve determines the amount of fuel injected into the cylinder 1. As the duration becomes longer, 1) is also increased. The electronic control unit 60 is configured to determine the engine load from the sum of the open durations of all the fuel injection valves 31. [ Since the electronic control unit 60 measures the length of the duration of the fuel injection valve 31, the electronic control unit 60 is perfectly delivered with the sum of the open durations of all the fuel injection valves 31.

      However, the characteristics of the fuel gas, such as the temperature, pressure and composition of the fuel gas delivered to the fuel injection valve 31, may fluctuate and thus cause inaccuracies in the calculation of the engine load. This can be a problem because the engine load is the most important control parameter for controlling the operation of the internal combustion engine. The engine load affects various aspects of internal combustion engine operation. For example, the pressure of the hydraulic system, the opening timing of the exhaust valve, the start timing of the fuel injection, the operation of the exhaust gas bypass and the opening of the valve in such exhaust gas bypass, the setting of the variable turbocharger, the activation / deactivation of the SCR operation The activation / deactivation gas pressure of the fuel gas, and the like.

        Therefore, it is important to receive the amount of energy injected through the fuel injection valve 31 during the opening timing of the fuel injection valve 31 accurately and without (substantial) delay. In the case of liquid fuels such as diesel oil, the changes due to the pressure, temperature and composition of the diesel oil are negligible, and thus the total open duration of the fuel valve can be used to determine the engine load of the internal combustion engine, You can make an accurate decision. Unfortunately, this does not apply to engines powered by fuel gas, since the changes in pressure, temperature and composition of the fuel gas are negligible.

      The engine is equipped with the system shown in Fig. 4 so that the engine load can be accurately determined from the open duration of the fuel injection valve 31. Fig.

      This system provides the information necessary to adjust the engine load calculation so that the engine load calculation can be based on the total duration of the fuel valve but can be based on the variation of the gas fuel supplied to the cylinder 1 to reach an accurate and immediate result Lt; / RTI >

       The gas fuel supply system 30 supplies the gaseous fuel to the cylinder 1 through the fuel valve 31 at a given temperature and pressure. The gas fuel supply system 30 also connects the fuel supply system 30 to the nozzles 49 and via the gas fuel supply conduit 41 including the valve 43 to the same fuel And supplies the gas to the combustion cell (40). Valve 43 may be used to shut off gas fuel supply conduit 41.

       The nozzle 49 injects the fuel gas into the combustion cell 40 through one or more holes in the nozzle 49. The size of the nozzle 49 is accurately determined by, for example, correction. Such engagement may be performed on the associated internal combustion engine fuel valve 31, or the correction may be an absolute correction. The size of the nozzle 49 is the size of one or more nozzle hole areas.

       The flow of the fuel gas to the combustion cell 40 is very small as compared with the flow of the fuel gas to the cylinder 1. It is preferable that the size of the nozzle 49 is relatively small as compared with the size of the fuel valve 31 in order to reduce the fuel gas flow to the combustion cell. Since the supply of fuel gas to the combustion cell 40 is the same fuel gas at the same pressure and temperature as the fuel gas delivered to the cylinder 1, the nozzle 49 can supply the fuel gas under the same conditions as the fuel valve 31 Accept.

       The supply line 42 supplies the flow of oxidant gas to the combustion cell 40. The oxidant gas reduces the oxygen content in the oxidant gas compared to mint air, for example as ambient air or ambient air diluted with nitrogen. When the ambient air is diluted with nitrogen, the oxidant gas has a lower oxygen ratio than the ambient air, so that the oxidant gas has the advantage that the combustion temperature is lower than the combustion of the fuel gas with air. In one embodiment, the combustion cell (40) is provided with cooling means for managing the temperature of the combustion cell (40).

       In one embodiment, the combustion cell 40 is provided with an oxidation catalyst during the combustion process. Such oxidation catalysts are well known in the art. Alternatively, the combustion cell 40 may be provided with a simple igniter, such as an electronic spark generator.

       In one embodiment, the supply line 42 includes a blower 44a, a venturi 45 and a control valve 46. [ The pressure of the venturi 45 is measured to determine the flow rate of oxidant gas to the combustion cell 40. The opening degree of the control valve 46 and the setting of the blower 44 are adjusted to control the flow rate of the oxidizing gas to the combustion cell 40. [

       The electronic control device 50 controls the operation of the system. In one embodiment, the electronic control device 50 controls the operation of the blower 44 and the electronic control valve 46. In one embodiment, the electronic control device 50 receives a signal from the pressure sensor of the venturi 45.

        The fuel gas is burned together with the oxidizing gas in the chamber of the combustion cell (40). The generated combustion gas is discharged from the combustion cell (40) via the exhaust conduit (47). The exhaust conduit 47 has a sensor 48 for measuring the proportion of oxygen in the flow of combustion gas. In one embodiment, the sensor 48 is a lambda sensor 48. The electronic control unit 50 receives a signal from the sensor 48.

       The stream of oxidizing gas is controlled to produce combustion in the combustion cell 40 under controlled conditions, i.e., a controlled stoichiometric coefficient. Preferably, the stoichiometric coefficient is maintained at 1 to 2. In one embodiment, it is preferred that combustion occurs with an exact stoichiometric condition, i.e., a stoichiometric coefficient of one.

       The stoichiometric coefficients are thereby controlled by the electronic control device 50 in response to the signal of the sensor 48 by controlling the operation of the blower 44 and / or the control valve 46 accordingly. The feedback of the sensor 48 is thus used to regulate the flow of oxidant gas.

       The ratio of oxygen mass required for combustion in the controlled stoichiometric coefficient is monitored, preferably continuously monitoring the signal from the venturi 45, for example in an electronic control unit.

       In another embodiment, the system may be set to an arrangement of supply lines 42 that maintain a constant oxygen mass ratio without any control operation of the electronic control device 50, Simply receives the value of a constant oxygen mass ratio and determines the ratio of oxygen mass used in the combustion process from a constant oxygen mass ratio and the ratio of oxygen measured in the combustion gas.

       The oxygen mass ratio is a direct measure of the chemical energy bound to the gas stream since it can release a predetermined amount of heat for a given mass of oxygen. The amount of heat that can be released per kilogram of air is about 3 MJ when the fuel gas is composed of hydrocarbons (and oxidant gas is air). Thus, the ratio of oxygen mass or air mass used in the combustion process is directly proportional to the amount of energy injected through the nozzle per unit of time. In one embodiment, since the size of the nozzle is corrected for the size of the fuel valve 31, it is possible to accurately know how much energy is injected through the fuel valve per unit of time by knowing the exact amount of energy injected through the nozzle 49 It becomes possible to decide. This in turn allows accurate calculation of the engine load by summing the open duration of the fuel valve 31.

       In one embodiment, the output signal of the system, such as a signal sent from the electronic control unit 50 to the electronic control unit 60, is used to calculate the engine load of the electronic control unit 60 from the actual It is a form of correction coefficient that corrects by the condition. Thus, the electronic control unit 60 can use the signal received from the electronic control unit 50 to adjust the engine load calculation, and thereby calculate the engine load more accurately.

       The nature of the signal sent from the electronic control unit 50 to the electronic control unit 60 depends on the manner in which the system operates. If the system is operated with a constant air flow or a constant oxygen mass flow to the combustion cell, then the resulting measured stoichiometric coefficient (measured, for example, with the lambda sensor 48) Lt; / RTI > may be an input signal that determines the correction that needs to be applied to the engine load calculation based on the open duration of the engine.

       If the system controls the magnitude of the oxidant gas flow and operates with a constant stoichiometric coefficient, the input signal from, for example, 1 to the electronic control unit 60 may be a signal from the pressure sensor of the venturi 45. Based on this signal, the electronic control unit 60 calculates the adjustment necessary for the engine load calculation. It is also possible to measure the mass flow of the oxidant gas in a manner other than using a venturi, such as using a heat ray sensor or a moving vane flow meter. Signals from the apparatus for measuring or determining the magnitude of the oxidant gas flow into the combustion cell 40 may be delivered to the electronic control unit 60 directly or via the electronic control unit 50. [

In one embodiment, the electronic control device 50 is configured to determine the calorific value of the fuel gas supply to the combustion cell 40 and to deliver the determined calorific value to the electronic control device 60. [ The calorific value can be expressed as Mw / mm ² .

       The electronic control unit 60 is delivered with the area of the holes in the fuel valve 31 nozzle relative to the size of the fuel valve 31, i.e. the size of the holes (or holes) area in the nozzle 49. The electronic control unit 60 can be further configured to determine the ratio between these two sizes and can determine the exact amount of energy flowing through the injection valve 31 based on this ratio.

       Although the electronic control device 50 and the electronic control device 60 have been described as separate electronic control devices, one single electronic control device including the function of the electronic control device 50 and the function of the electronic control device 60, It is possible to provide it to the user.

       In one embodiment, the combustion cell 40 is calibrated using a known gas, preferably pure gas, such as pure methane. That is, the nozzle size is determined. The required oxygen consumption is determined for the combustion cell 40 with a known gas, and all other gases process the deviation based on that case.

        5 is a flow chart illustrating the operation of the system. The flowchart illustrates the principle of the method, and the box in the flowchart does not illustrate successive steps. The method is used to determine the characteristics of the fuel gas in an internal combustion engine operated with fuel gas. The method includes supplying the fuel gas to the cylinder 1 of the engine at a given pressure and temperature and supplying the flow of fuel gas to the combustion cell 40 at the same pressure and temperature.

      The method includes the steps of supplying a flow of oxidant gas to the combustion cell (40), generating a flow of the combustion gas by burning the fuel gas with the oxidant gas in the combustion cell (40) and measuring the oxygen ratio in the combustion gas .

       The method includes determining or controlling the oxygen mass ratio of the oxidant gas flow fed to the combustion cell (40). The control of the oxygen mass ratio in the oxidant gas flow supplied to the combustion cell 40 is preferably made corresponding to the rate of measurement of oxygen in the combustion gas.

       The method includes calculating the engine load based on the time when the fuel inlet valve 31 of the engine is opened and adjusting the calculated engine load based on the calculation of the oxygen mass ratio used in the combustion process. The latter step may include calculating the ratio of the mass of oxygen supplied to the combustion cell 40 or the ratio of the mass of oxygen used for combustion based on the determination or determination of the stoichiometric coefficient associated with the determination.

       In one embodiment, the method may also include determining a value indicative of the exothermic character of the fuel gas. The method may comprise the step of using in an embodiment to measure or determine the heating characteristics of the fuel in a calculation for determining an engine load.

  The invention has been described in conjunction with various embodiments thereof. However, other modifications to the disclosed embodiments can be understood and effected by those skilled in the art, practicing the claimed invention, from the study of the drawings, the disclosure and the appended claims. In the claims, the word " comprises "does not exclude other elements or steps, and the expression" one " The mere fact that certain measures are quoted in different dependent claims does not indicate that the combination of those used in the solution can not be used advantageously. Reference signs used in the claims should not be construed as limiting the scope.

30: fuel gas supply system 31: fuel inlet valve
40: combustion cell 42: supply line
47: exhaust conduit 48: sensor

Claims (22)

In the internal combustion engine,
At least one cylinder (1);
A fuel gas supply system (30) configured to supply a flow of fuel gas to the cylinder (1) at a given pressure and temperature; And
At least one fuel inlet valve (31) provided in each of the one or more cylinders (1)
Combustion cell (40);
The fuel gas supply system (30) configured to supply a flow of the fuel gas to the combustion cell (40) at the same given pressure and temperature;
A supply line (42) for supplying a flow of oxidant gas to the combustion cell (40);
An exhaust conduit 47 for transferring the flow of combustion gas from the combustion cell 40; And
And a sensor (48) for measuring a ratio of oxygen in the flow of the combustion gas. The method according to claim 1,
And an apparatus (44, 45) for maintaining a constant oxygen mass ratio in the flow of the oxidant gas. The method according to claim 1,
And an apparatus (44, 45, 50) for controlling the oxygen mass ratio in the flow of the oxidant gas. The method according to any one of claims 1 to 3,
And an apparatus (45) for measuring or determining the flow rate of the oxidant gas supplied to the combustion cell (40) or the oxygen mass flow rate in the oxidant gas flow supplied to the combustion cell (40). The method according to any one of claims 1 to 4,
Characterized by further comprising a control device (50) for receiving the oxygen mass ratio in the oxidant gas flow to the combustion cell (40) and receiving a signal from the sensor (48) for measuring the oxygen ratio in the combustion gas flow Internal combustion engine. The method of claim 5,
Wherein the control device (50) is configured to determine the amount of oxygen consumed during combustion in the combustion cell (40). The method according to claim 5 or 6,
The control device 50 is further adapted to control the flow rate of oxygen in the oxidizing gas flow based on a signal from the sensor 48 for measuring the ratio of the signal from the device 45 for measuring or determining the mass ratio of oxygen in the oxidizing gas flow to oxygen in the combustion gas flow Is configured to determine the energy injected through the nozzle (49). The method according to claim 6 or 7,
Wherein the control device (50) is configured to determine a value indicating a calorific value of the fuel gas supplied to the cylinder (1) and the combustion cell (40). The method according to any one of claims 1 to 8,
The controller 50 may control the amount of energy injected through the nozzle 49 or the value of the amount of the fuel gas supplied to the combustion chamber 40, Is configured to determine the energy injected or injected through the fuel inlet valve (31) into the cylinder (1). The method of claim 9,
Wherein the control device (50) is configured to determine an engine load from the amount of energy injected or injected into the one or more cylinders (1) via the fuel inlet valve (31). The method according to any one of claims 1 to 10,
Wherein the control device (50) receives the relationship between the size of the nozzle (49) and the size of the fuel inlet valve (31). The method according to any one of claims 1 to 11,
Wherein the control device (50) receives the correct size of the nozzle (49) and the correct size of the fuel inlet valve (31), preferably by correcting. The method according to any one of claims 9 to 12,
Wherein the controller (50) is configured to use a value indicating a calorific value of the fuel gas supplied to the cylinder (1) and the combustion cell (40) as a correction coefficient for calculating an engine load. . The method according to any one of claims 1 to 13,
Wherein the oxidant gas is a mixture of nitrogen and air. The method according to any one of claims 1 to 14,
Wherein the oxygen content of the oxidant gas is lower than the oxygen content of the ambient air. The method according to any one of claims 1 to 15,
Characterized in that the sensor (48) for determining the oxygen ratio in the combustion gas flow comprises a lambda sensor (48). The method according to any one of claims 5 to 16,
The control device (50) is operable to determine the ratio of oxygen in the combustion gas And controls the oxygen mass ratio or the flow rate of the oxidizing gas in response to the signal from the sensor (48). A method for determining a characteristic of a fuel gas in an internal combustion engine operated with fuel gas, the method comprising:
Supplying the fuel gas to the cylinder 1 of the engine at a given pressure and temperature and supplying the flow of fuel gas to the fuel cell 40 at the same pressure and temperature,
Supplying a flow of oxidant gas to the combustion cell (40);
Generating a flow of the combustion gas by combusting the fuel gas with the oxidant gas in the combustion cell (40); And
And measuring the oxygen ratio in the combustion gas. 19. The method of claim 18,
Further comprising determining or controlling a mass ratio of oxygen in the oxidant gas flow, preferably corresponding to a ratio of oxygen measured in the combustion gas. The method according to claim 18 or 19,
Further comprising determining a value indicative of a heating characteristic of the fuel gas. The method of claim 20,
Further comprising the step of determining the engine load based on a duration that the fuel inlet valve (31) of the engine is open and a value indicative of a heating characteristic of the fuel gas. The method according to any one of claims 17 to 21,
Further comprising the step of determining the amount of oxygen consumed during combustion of the combustion cell (40).

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