Fuel engine emission calculation method and system based on hydrogen balance method, and medium

Abstract

The application discloses a fuel engine emission calculation method and system based on a hydrogen balance method, and a medium, and relates to the technical field of data processing. The method first acquires data such as fuel components, emission concentration, intake air flow, temperature and humidity; then calculates actual exhaust mass flow according to the intake air flow or fuel flow; and finally calculates the pollutant mass flow in combination with the exhaust molar mass, NO x Correction coefficient and pollutant concentration. The system comprises data acquisition, exhaust flow calculation and pollutant flow calculation units. The application replaces carbon balance with hydrogen balance, is not limited by the carbon content of fuel, is suitable for high-hydrogen, methanol, pure hydrogen, pure ammonia and other low-carbon and zero-carbon fuels, couples intake air humidity, supercharging intercooling and exhaust component correction, significantly improves the exhaust flow and pollutant emission calculation accuracy, solves the problem that the traditional carbon balance method is invalid under zero-carbon fuel, and is suitable for precise calculation and authentication of emissions of various engines.

Description

Technical Field

[0001] This invention relates to the field of data processing technology, and in particular to a method, system, and medium for calculating emissions from fuel engines based on the hydrogen balance method. Background Technology

[0002] The transportation sector and industrial combustion equipment are currently undergoing an accelerated transformation and upgrading of their energy structure, gradually shifting from traditional fossil fuels such as gasoline and diesel to low-carbon and zero-carbon fuels (such as ammonia, hydrogen, methanol, and various synthetic fuels). However, the increasing diversification of fuel types and the significant changes in the proportion of hydrogen in new fuel formulations present new technical challenges to existing engine emissions calculation methods.

[0003] Exhaust flow rate is a core parameter in engine emission calculations, and its accuracy directly determines the precision of pollutant emission calculations and the reliability of emission assessment results. Currently, the industry generally uses the carbon balance method, based on the principle of carbon conservation, to indirectly calculate exhaust flow rate by measuring fuel consumption and carbon oxide concentration in exhaust. This method is mature in traditional hydrocarbon fossil fuel engines, offering advantages such as high accuracy and stability. However, with the widespread application of low-carbon fuels (such as methanol and highly hydrogen-blended fuels) and zero-carbon fuels (such as ammonia and pure hydrogen), the traditional carbon balance calculation method has revealed significant technical deficiencies and faces the risk of failure. Since the combustion products of zero-carbon fuels contain almost no carbon, continuing to use the original carbon balance method for exhaust flow rate and emission calculations will result in a significant reduction in calculation accuracy, failing to meet the industry's technical requirements for accurate emission detection, energy efficiency assessment, and emission control of new fuel engines.

[0004] In summary, there is an urgent need to develop an emission calculation method and supporting system that can be adapted to low-carbon and zero-carbon fuel engines, in order to break through the fuel applicability limitations of traditional methods, improve the emission calculation theory and technology system of new fuel engines, and provide accurate data support for energy efficiency optimization, combustion matching and emission control of new fuel engines. Summary of the Invention

[0005] In view of the technical problems mentioned in the background, the purpose of this invention is to provide a method, system, and medium for calculating emissions from fuel engines based on the hydrogen balance method, so as to meet the emission calculation requirements of low-carbon and zero-carbon fuel engines.

[0006] To achieve the objectives of this invention, the technical solution provided by this invention is as follows: First aspect This invention provides a method for calculating emissions from fuel engines based on the hydrogen balance method, comprising the following steps: Step 1: Obtain fuel composition data, pollutant emission concentration data at various test operating points of the engine, intake relative humidity, intake temperature, intake total pressure, and one of the following: humid air intake flow rate and fuel flow rate; Step 2: Calculate the actual exhaust mass flow rate using one of the following methods, as detailed below: The first method: When obtaining the humid air intake flow rate, the actual exhaust mass flow rate is calculated using the following formula: ; The second method: When obtaining the fuel flow rate, the actual exhaust mass flow rate is calculated using the following formula: ; in, The actual exhaust mass flow rate is kg / h; The intake flow rate of humid air is kg / h; Fuel flow rate, kg / h; Theoretical air-fuel ratio; The excess air coefficient is a normalized factor based on fuel composition, intake air absolute humidity, and hydrogen. Intake humidity coupling coefficient Comprehensive conversion factor for exhaust components Excess air coefficient coupling correction coefficient Calculated; The absolute humidity of the intake air is gH2O / kg dry air, calculated based on the relative humidity of the intake air. Step 3: Based on actual exhaust mass flow rate The mass flow rates of each emitted pollutant are calculated as follows: ; in, To discharge pollutants Mass flow rate, kg / h; This is the NOx emission correction factor; If is a constant, If the unit is ppm, then ,like If the unit is %, then ; pollutants molar mass With exhaust molar mass The ratio; pollutants The concentration, % or ppm.

[0007] Second aspect This invention provides a fuel engine emission calculation system based on the hydrogen balance method, used to execute the fuel engine emission calculation method based on the hydrogen balance method, including the following units: a data acquisition unit, an actual exhaust mass flow rate calculation unit, and an emission pollutant mass flow rate calculation unit; The data acquisition unit is used to acquire fuel component data, pollutant emission concentration data at various test operating points of the engine, intake relative humidity, intake temperature, intake total pressure, and one of the following: humid air intake flow rate and fuel flow rate. The actual exhaust mass flow rate calculation unit is used to calculate the actual exhaust mass flow rate using one of the following methods, as follows: The first method: When obtaining the humid air intake flow rate, the actual exhaust mass flow rate is calculated using the following formula: ; The second method: When obtaining the fuel flow rate, the actual exhaust mass flow rate is calculated using the following formula: ; in, The actual exhaust mass flow rate is kg / h; The intake flow rate of humid air is kg / h; Fuel flow rate, kg / h; Theoretical air-fuel ratio; The excess air coefficient is a normalized factor based on fuel composition, intake air absolute humidity, and hydrogen. Intake humidity coupling coefficient Comprehensive conversion factor for exhaust components Excess air coefficient coupling correction coefficient Calculated; The absolute humidity of the intake air is gH2O / kg dry air; The pollutant emission mass flow rate calculation unit is used to calculate the actual exhaust mass flow rate. The mass flow rates of each emitted pollutant are calculated as follows: ; in, To discharge pollutants Mass flow rate, kg / h; This is the NOx emission correction factor; If is a constant, If the unit is ppm, then ,like If the unit is %, then ; pollutants molar mass With exhaust molar mass The ratio; pollutants The concentration, % or ppm.

[0008] Third aspect The present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the aforementioned method for calculating fuel engine emissions based on the hydrogen balance method.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention uses the hydrogen balance method to replace the traditional carbon balance method. It uses hydrogen as the conservation benchmark for calculations and no longer depends on the carbon content in the fuel. It can be stably applied to engines with zero-carbon fuels such as pure hydrogen and ammonia, as well as low-carbon fuels such as methanol and highly hydrogen-blended fuels. It can effectively solve the technical problems of calculation failure and significant decrease in accuracy of the traditional carbon balance method under zero-carbon and low-carbon fuels, and achieve full coverage compatibility with multiple types of new fuels. Furthermore, this invention constructs a calculation model based on hydrogen benchmark normalization, coupled with real-time corrections for multiple factors such as intake air humidity, condensate during boosting, water vapor in the exhaust, hydrogen, and ammonia. This allows for accurate calculation of the theoretical air-fuel ratio, excess air coefficient, exhaust molar mass, and NO. x By adjusting key parameters such as correction coefficients, high-precision calculations of exhaust mass flow rate and mass flow rate of various pollutants are achieved. The calculation results are closer to the actual combustion state, meeting the stringent requirements for engine emission certification and precise control. Attached Figure Description

[0010] Figure 1 A schematic diagram of the fuel engine emission calculation method based on the hydrogen balance method provided in an embodiment of the present invention; Figure 2 This is a schematic diagram comparing the results of the traditional carbon balance method and the solution of this invention in a test example. Detailed Implementation

[0011] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0012] It should be noted that the user data involved in the embodiments of this application are all authorized, and the acquisition, processing, and transmission comply with legal and regulatory requirements, and necessary confidentiality measures have been taken.

[0013] like Figure 1As shown, this embodiment provides a method for calculating fuel engine emissions based on the hydrogen balance method, including the following steps: Step 1: Obtain fuel composition data, pollutant emission concentration data at various test operating points of the engine, intake relative humidity, intake temperature, intake total pressure, and one of the following: humid air intake flow rate and fuel flow rate; It should be noted that fuel composition data includes the mass fractions of C, H, O, N, and S in the fuel, and the pollutant emission concentrations at various test operating points of the engine include... , , The parameters include wet-based emission concentration, intake relative humidity, intake temperature, intake total pressure, and one of the following: wet air intake flow rate and fuel flow rate; if it is a turbocharged engine, it should also include the intake pressure after turbocharging and intercooling and the intake temperature after turbocharging and intercooling.

[0014] Step 2: Calculate the actual exhaust mass flow rate using one of the following methods, as detailed below: The first method: If the intake flow rate of moist air is known. It can be calculated using the following formula: ; The second method: If the fuel flow rate is known. It can be calculated using the following formula: ; in, The actual exhaust mass flow rate is kg / h; The humid air intake flow rate, in kg / h, can be obtained through testing; Fuel flow rate, kg / h; Theoretical air-fuel ratio; The excess air coefficient is a normalized factor based on fuel composition, intake air absolute humidity, and hydrogen. Intake humidity coupling coefficient Comprehensive conversion factor for exhaust components Excess air coefficient coupling correction coefficient Calculated; The absolute humidity of the intake air is gH2O / kg dry air, calculated based on the relative humidity of the intake air. Preferably, the theoretical air-fuel ratio The calculation method is as follows: ; in, For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For elements The molar mass, g / mol; For elements The molar mass, g / mol; For elements The molar mass, g / mol; For elements The molar mass, g / mol; The molar mass of dry air is taken as 28.96559 g / mol; The dry air O2 concentration is taken as 20.94482%.

[0015] Preferably, based on fuel composition, intake air humidity, and 、 、 、 Calculate the excess air coefficient The excess air coefficient refers to the ratio of the actual amount of air supplied for fuel combustion to the theoretical amount of air, and is an important parameter reflecting the fuel-air ratio. Under complete combustion conditions, carbon, hydrogen, and sulfur in the fuel are oxidized to carbon dioxide, water, and sulfur dioxide, respectively, while nitrogen in the fuel reacts completely to form nitrogen gas, so there is no oxygen requirement. Therefore, the theoretical oxygen requirement for fuel combustion can be calculated from the elemental composition of the fuel in the oxidation reaction. However, under actual operating conditions, due to the influence of factors such as intake air humidity, incomplete combustion, and by-product formation, the actual amount of oxygen participating in the reaction deviates from the theoretical value. Therefore, this invention constructs an excess air coefficient calculation model based on the hydrogen balance principle and under the hydrogen element normalization benchmark. The denominator represents the theoretical oxygen requirement per unit of fuel under ideal complete combustion conditions, and is combined with intake air humidity and exhaust component distribution, through... The correction is made, with the numerator representing the actual effective oxygen supply to combustion. This is based on the intake oxygen content and incorporates components such as water vapor, hydrogen, and ammonia in the exhaust gas. A conversion correction is performed; by constructing the ratio relationship between the numerator and denominator, a quantitative characterization of the deviation between oxygen supply and oxygen demand during actual combustion is achieved, thereby obtaining the excess air coefficient. Specifically, the excess air coefficient... The calculation method is as follows: ; in, For matter The molar mass, g / mol; Among them, calculations are based on fuel composition and pollutant exhaust concentration. . This parameter is constructed based on the molar proportions of oxygen and nitrogen in the fuel and the gas-liquid distribution of water vapor in the exhaust gas. It is used to unify the elemental composition of the fuel and the exhaust gas components under a hydrogen molar reference, thereby establishing a consistent scale for element conservation relationships. Specifically, The calculation method is as follows: ; in, For elements The molar mass, g / mol; For emissions The wet basis concentration, % For emissions Wet basis concentration, ppm; For the equilibrium constant, a value of 3.5 is recommended. Preferably, It is used to reflect the correction effect of the actual exhaust composition on the calculation, so that the excess air coefficient calculation is closer to the actual combustion product distribution. The calculation method is as follows: ; in, For emissions Wet basis concentration, ppm; Preferably, the excess air coefficient coupling correction coefficient The normalized coefficient based on hydrogen Coupling coefficient with intake air humidity Based on this, the influence of components such as water vapor, hydrogen, and ammonia in the exhaust gas is comprehensively introduced, and the intake humidity conditions are coupled with the actual distribution of combustion products in a unified manner. This ultimately achieves an overall correction between the theoretical oxygen demand and the measured exhaust gas, ensuring the accuracy of the excess air coefficient calculation. The calculation method is as follows: .

[0016] in, It is used to characterize the molar mass relationship between water vapor and dry air in intake air, and to reflect the correction effect of water vapor condensation on actual intake air humidity under turbocharging and intercooling conditions. The calculation method is as follows: ; in, To correct for humidity, the absolute humidity of the intake air after the intercooler is taken. and The smaller value in; For turbocharged intercooled engines, the water condensing and being discharged from the intercooler alters the humidity of the intake air, requiring humidity correction, i.e., in the formula... After the air is cooled by the intercooler, its saturated moisture content decreases. Water vapor exceeding the saturation limit will condense into liquid water and be discharged. Therefore, the actual absolute humidity of the air entering the cylinder will not exceed the saturated absolute humidity corresponding to the temperature after intercooling. To accurately reflect the true intake air humidity, the absolute humidity of the intake air after turbocharging and intercooling is calculated. and will and Compare the two values ​​and take the smaller one as the corrected humidity. .

[0017] Preferably, the absolute humidity of the intake air Absolute humidity of intake air after turbocharging and intercooling The calculation method is as follows: ; ; in, The relative humidity of the intake air, expressed as %, can be obtained through testing; The intake total pressure, in kPa, can be obtained through testing; Intake air temperature The saturated vapor pressure of air at that time, kPa; The intake air temperature, in °C, can be obtained through testing. ; ; in, The intake pressure after intercooling is boosted, in kPa, and can be obtained through testing. The pressure is the saturated vapor pressure (kPa) corresponding to the temperature after pressurization and intercooling. The intake temperature after turbocharging and intercooling is ℃, which can be obtained through testing.

[0018] Preferably, the NOx emission correction factor The calculation methods differ depending on the type of engine and the influencing factors.

[0019] The NOx emission correction factor The calculation method is as follows: (1) For igniting the engine, The calculation method is as follows: ; (2) For naturally aspirated compression ignition engines, The calculation method is as follows: ; (3) For turbocharged intercooled compression ignition engines, The calculation method is as follows: ; in, The reference boosted air temperature (°C) for each test point is specified by the engine manufacturer.

[0020] Preferably, based on pollutant concentration and 、 、 、 Molar mass of exhaust gas calculate. The equivalent molar mass of humid air, obtained by combining the absolute humidity of the intake air, the molar mass of dry air, and the corrected intake air humidity parameters, is used to reflect the contribution of the intake air and the water vapor it contains to the average molar mass of the exhaust. To characterize the effect of fuel elemental composition on exhaust molar mass, this method normalizes the mass fraction of each element in the fuel and performs a scaling transformation based on hydrogen, thereby establishing an equivalent mapping relationship between fuel composition and the molar mass of combustion products. Exhaust molar mass The average molar mass of the mixture is determined by the baseline exhaust system generated from intake air and fuel combustion, and a correction term for the disturbance of each measurable pollutant component on the average molar mass of the mixture is superimposed on this baseline. The baseline term reflects the dry exhaust composition under ideal complete combustion conditions, while the correction term describes the effect of changes in the concentrations of components such as water vapor, hydrogen, and ammonia on the exhaust molar mass. The calculation method is as follows: ; in, ; .

[0021] Step 3: Based on actual exhaust mass flow rate The mass flow rates of each emitted pollutant are calculated as follows: ; in, To discharge pollutants Mass flow rate, kg / h; This is the NOx emission correction factor; If is a constant, If the unit is ppm, then ,like If the unit is %, then ; pollutants molar mass With exhaust molar mass The ratio; pollutants The concentration, % or ppm.

[0022] Test case Based on a zero-carbon fuel hydrogen engine, the engine intake air mass flow rate and fuel flow rate were tested at 10 operating points on a test bench, and the results were summed to obtain the actual exhaust mass flow rate. Then, based on the tested fuel composition, pollutant emission concentrations at each test operating point, intake relative humidity, intake temperature, intake total pressure, intake pressure after turbocharging and intercooling, intake temperature after turbocharging and intercooling, and either the humid air intake flow rate or the fuel flow rate, the exhaust mass flow rate was calculated using both the traditional carbon balance method and the method of this invention. The test results of the exhaust mass flow rate under the same operating conditions are as follows: Figure 2 As shown.

[0023] Figure 2 In this context, "actual test" refers to the result obtained by adding together the measured engine intake air mass flow rate and fuel flow rate. Traditional carbon balance method: refers to the results obtained through calculations using the traditional carbon balance method; Hydrogen balance method: refers to the result obtained by using the technical solution of this invention - the intake flow rate is known, and the calculation is performed in step 2 using the first method; Hydrogen balance method: refers to the result obtained by using the technical solution of this invention - known fuel flow rate, and the calculation in step 2 using the second method; The above analysis shows that when using the traditional carbon balance method to calculate the exhaust mass flow rate of a zero-carbon engine, the result differs significantly from the actual test value, being only about 12% of the original value; while the calculation result using the hydrogen balance method of this invention is much closer to the actual test value. The errors in calculating the exhaust mass flow rate using the traditional carbon balance method and the hydrogen balance method are shown in Table 1.

[0024] Table 1

[0025] As can be seen from the above analysis, for zero-carbon fuel hydrogen engines, the traditional carbon balance method is completely ineffective due to the absence of carbon elements, with an error of about 88%, making it impossible to calculate exhaust mass flow rate; while the hydrogen balance method of this invention calculates normally and is stable throughout the process, with an error of ≤3.5% relative to the actual exhaust mass flow rate, significantly improving the accuracy of subsequent pollutant mass flow rate calculation.

[0026] Meanwhile, through experiments and calculations, it was found that when calculating the exhaust mass flow rate of a methanol engine using the traditional carbon balance method, the error reached 20%; however, when using the hydrogen balance method of this invention, the calculated exhaust mass flow rate was closer to the actual value, and the result was reliable.

[0027] In addition, this embodiment also provides a fuel engine emission calculation system based on the hydrogen balance method, used to execute the fuel engine emission calculation method based on the hydrogen balance method, including the following units: a data acquisition unit, an actual exhaust mass flow rate calculation unit, and an emission pollutant mass flow rate calculation unit; The data acquisition unit is used to acquire fuel component data, pollutant emission concentration data at various test operating points of the engine, intake relative humidity, intake temperature, intake total pressure, and one of the following: humid air intake flow rate and fuel flow rate. The actual exhaust mass flow rate calculation unit is used to calculate the actual exhaust mass flow rate using one of the following methods, as follows: The first method: When obtaining the humid air intake flow rate, the actual exhaust mass flow rate is calculated using the following formula: ; The second method: When obtaining the fuel flow rate, the actual exhaust mass flow rate is calculated using the following formula: ; in, The actual exhaust mass flow rate is kg / h; The intake flow rate of humid air is kg / h; Fuel flow rate, kg / h; Theoretical air-fuel ratio; The excess air coefficient is a normalized factor based on fuel composition, intake air absolute humidity, and hydrogen. Intake humidity coupling coefficient Comprehensive conversion factor for exhaust components Excess air coefficient coupling correction coefficient Calculated; The absolute humidity of the intake air is gH2O / kg dry air, calculated based on the relative humidity of the intake air. The pollutant emission mass flow rate calculation unit is used to calculate the actual exhaust mass flow rate. The mass flow rates of each emitted pollutant are calculated as follows: ; in, To discharge pollutants Mass flow rate, kg / h; This is the NOx emission correction factor; If is a constant, If the unit is ppm, then ,like If the unit is %, then ; pollutants molar mass With exhaust molar mass The ratio; pollutants The concentration, % or ppm.

[0028] Preferably, the theoretical air-fuel ratio The calculation method is as follows: ; in, For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For elements The molar mass, g / mol; For elements The molar mass, g / mol; For elements The molar mass, g / mol; For elements The molar mass, g / mol; The molar mass of dry air is taken as 28.96559 g / mol; The dry air O2 concentration is taken as 20.94482%.

[0029] Preferably, the excess air coefficient The calculation method is as follows: ; in, For matter The molar mass, g / mol; The hydrogen-based normalization coefficient; This is the intake air humidity coupling coefficient; This refers to the comprehensive conversion factor for exhaust components; The excess air coefficient is the coupling correction coefficient, based on Intake humidity coupling coefficient Calculated; in, The calculation method is as follows: ; in, For elements The molar mass, g / mol; For emissions The wet basis concentration, % For emissions Wet basis concentration, ppm; For the equilibrium constant, a value of 3.5 is recommended. in, The calculation method is as follows: ; in, For emissions Wet basis concentration, ppm; ; in, The calculation method is as follows: ; in, To correct for humidity, the absolute humidity of the intake air after the intercooler is taken. and The smaller value in the range.

[0030] In addition, this embodiment also provides a computer-readable storage medium storing a computer program thereon, characterized in that the computer program, when executed by a processor, implements the aforementioned fuel engine emission calculation method based on the hydrogen balance method.

[0031] Finally, it should be noted that the above embodiments are merely illustrative and explanatory of the present invention, and are not intended to limit the present invention to the scope of the described embodiments. Furthermore, those skilled in the art will understand that the present invention is not limited to the above embodiments, and many more variations and modifications can be made based on the teachings of the present invention, all of which fall within the scope of protection claimed by the present invention.

Claims

1. A method for calculating emissions from a fuel engine based on the hydrogen balance method, wherein the fuel engine is a low-carbon or zero-carbon engine, characterized in that, Includes the following steps: Step 1: Obtain fuel composition data, pollutant emission concentration data at various test operating points of the engine, intake relative humidity, intake temperature, intake total pressure, and one of the following: humid air intake flow rate and fuel flow rate; Step 2: Calculate the actual exhaust mass flow rate using one of the following methods, as detailed below: The first method: When obtaining the humid air intake flow rate, the actual exhaust mass flow rate is calculated using the following formula: ； The second method: When obtaining the fuel flow rate, the actual exhaust mass flow rate is calculated using the following formula: ； in, The actual exhaust mass flow rate is kg / h; The intake flow rate of humid air is kg / h; Fuel flow rate, kg / h; Theoretical air-fuel ratio; The excess air coefficient is a normalized factor based on fuel composition, intake air absolute humidity, and hydrogen. Intake humidity coupling coefficient Comprehensive conversion factor for exhaust components Excess air coefficient coupling correction coefficient Calculated; The absolute humidity of the intake air is gH2O / kg dry air, calculated based on the relative humidity of the intake air. Step 3: Based on actual exhaust mass flow rate The mass flow rates of each emitted pollutant are calculated as follows: ； in, To discharge pollutants Mass flow rate, kg / h; This is the NOx emission correction factor; If is a constant, If the unit is ppm, then ,like If the unit is %, then ; pollutants molar mass With exhaust molar mass The ratio; pollutants The concentration, % or ppm.

2. The method for calculating fuel engine emissions based on the hydrogen balance method according to claim 1, characterized in that, The theoretical air-fuel ratio The calculation method is as follows: ； in, For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For elements The molar mass, g / mol; For elements The molar mass, g / mol; For elements The molar mass, g / mol; For elements The molar mass, g / mol; The molar mass of dry air is taken as 28.96559 g / mol; The dry air O2 concentration is taken as 20.94482%.

3. The method for calculating fuel engine emissions based on the hydrogen balance method according to claim 2, characterized in that, The excess air coefficient The calculation method is as follows: ； in, For matter The molar mass, g / mol; in, The calculation method is as follows: ； in, For elements The molar mass, g / mol; For emissions The wet basis concentration, % For emissions Wet basis concentration, ppm; It is the equilibrium constant; in, The calculation method is as follows: ； in, For emissions Wet basis concentration, ppm; in, The calculation method is as follows: ； in, The calculation method is as follows: ； in, To correct for humidity, the absolute humidity of the intake air after the intercooler is taken. and The smaller value in the range.

4. The method for calculating fuel engine emissions based on the hydrogen balance method according to claim 3, characterized in that, The absolute humidity of the intake air Absolute humidity of intake air after turbocharging and intercooling The calculation method is as follows: ； ； in, The relative humidity of the intake air is %; The total intake pressure is expressed in kPa. Intake air temperature The saturated vapor pressure of air at that time, kPa; Intake air temperature, °C; ； ； in, The intake pressure after intercooling is increased, in kPa; The pressure is the saturated vapor pressure (kPa) corresponding to the temperature after pressurization and intercooling. The intake temperature after turbocharging and intercooling is ℃.

5. The method for calculating fuel engine emissions based on the hydrogen balance method according to claim 4, characterized in that, The NOx emission correction factor The calculation method is as follows: (1) For igniting the engine, The calculation method is as follows: ； (2) For naturally aspirated compression ignition engines, The calculation method is as follows: ； (3) For turbocharged intercooled compression ignition engines, The calculation method is as follows: ； in, The reference boost air temperature, in °C, is specified by the engine manufacturer for each test point.

6. The method for calculating fuel engine emissions based on the hydrogen balance method according to claim 5, characterized in that, The exhaust molar mass The calculation method is as follows: ； in, ; 。 7. A fuel engine emission calculation system based on the hydrogen balance method, used to execute the fuel engine emission calculation method based on the hydrogen balance method as described in any one of claims 1-6, characterized in that, It includes the following units: a data acquisition unit, an actual exhaust gas mass flow rate calculation unit, and an emission pollutant mass flow rate calculation unit; The data acquisition unit is used to acquire fuel component data, pollutant emission concentration data at various test operating points of the engine, intake relative humidity, intake temperature, intake total pressure, and one of the following: humid air intake flow rate and fuel flow rate. The actual exhaust mass flow rate calculation unit is used to calculate the actual exhaust mass flow rate using one of the following methods, as follows: The first method: When obtaining the humid air intake flow rate, the actual exhaust mass flow rate is calculated using the following formula: ； The second method: When obtaining the fuel flow rate, the actual exhaust mass flow rate is calculated using the following formula: ； in, The actual exhaust mass flow rate is kg / h; The intake flow rate of humid air is kg / h; Fuel flow rate, kg / h; Theoretical air-fuel ratio; The excess air coefficient is a normalized factor based on fuel composition, intake air absolute humidity, and hydrogen. Intake humidity coupling coefficient Comprehensive conversion factor for exhaust components Excess air coefficient coupling correction coefficient Calculated; The absolute humidity of the intake air is gH2O / kg dry air, calculated based on the relative humidity of the intake air. The pollutant emission mass flow rate calculation unit is used to calculate the actual exhaust mass flow rate. The mass flow rates of each emitted pollutant are calculated as follows: ； in, To discharge pollutants Mass flow rate, kg / h; This is the NOx emission correction factor; If is a constant, If the unit is ppm, then ,like If the unit is %, then ; pollutants molar mass With exhaust molar mass The ratio; pollutants The concentration, % or ppm.

8. A fuel engine emission calculation system based on the hydrogen balance method according to claim 7, characterized in that, The theoretical air-fuel ratio The calculation method is as follows: ； in, For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For fuel Element mass fraction, % For elements The molar mass, g / mol; For elements The molar mass, g / mol; For elements The molar mass, g / mol; For elements The molar mass, g / mol; The molar mass of dry air is taken as 28.96559 g / mol; The dry air O2 concentration is taken as 20.94482%.

9. A fuel engine emission calculation system based on the hydrogen balance method according to claim 8, characterized in that, The excess air coefficient The calculation method is as follows: ； in, For matter The molar mass, g / mol; in, The calculation method is as follows: ； in, For elements The molar mass, g / mol; For emissions The wet basis concentration, % For emissions Wet basis concentration, ppm; It is the equilibrium constant; in, The calculation method is as follows: ； in, For emissions Wet basis concentration, ppm; in, The calculation method is as follows: ； in, The calculation method is as follows: ； in, To correct for humidity, the absolute humidity of the intake air after the intercooler is taken. and The smaller value in the range.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the fuel engine emission calculation method based on the hydrogen balance method as described in any one of claims 1-6.

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