A method for calculating and correcting the thermophysical properties of single-component hydrocarbon fuels

Abstract

The invention discloses a method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel. The method comprises the following steps: selecting a single-component hydrocarbon fuel to be analyzed and inputting operating parameters; calculating the potential energy of a molecular system of the single-component hydrocarbon fuel to be analyzed, heat flux in various directions and fluctuation data of stress; and calculating the thermophysical properties of the single-component hydrocarbon fuel under the input operating parameters; the thermophysical properties include thermodynamic properties, energy properties and transport properties; correcting the thermophysical properties of the single-component hydrocarbon fuel under the input operating conditions based on stability and kernel density estimation to obtain a thermophysical property data set; and finding the intersection of each thermophysical property data set of the single-component hydrocarbon fuel under the input operating conditions corrected based on stability and each thermophysical property data set of the single-component hydrocarbon fuel under the input operating conditions corrected based on kernel density estimation, and taking the average value of the data in the intersection as the corrected thermophysical property value.

Description

Technical Field

[0001] The invention relates to the technical fields of power engineering, engineering thermal physics, micro-nanoscale calculation and the like, and in particular to a method for calculating and correcting the thermal properties of a single-component hydrocarbon fuel. Background Art

[0002] Under the background of "dual carbon", the application of hydrocarbon fuels has expanded to high temperature and high pressure conditions. The injection process is often accompanied by gas-liquid phase change phenomena such as cavitation and flash boiling, which makes the comprehensive acquisition of thermophysical properties more complicated.

[0003] Currently, the thermophysical properties of hydrocarbon fuels are mostly obtained based on limited working conditions at room temperature and pressure, and there is a lack of methods for obtaining thermophysical properties under high temperature and high pressure environments. Existing thermophysical databases, such as the National Institute of Standards and Technology (NIST), predict the thermophysical properties of hydrocarbon fuels under high temperature and high pressure by interpolation fitting and other means, but the accuracy is limited and there is no comprehensive calculation method for thermophysical properties such as thermodynamic properties, energy properties and transport properties.

[0004] Traditional molecular dynamics can provide detailed atomic-level information from a microscopic level. However, since the simulation at the atomic scale has not considered the role of electrons or even more microscopic structures, and the force field potential energy parameters are inaccurate, the calculated results are somewhat different from the true values. Therefore, when using traditional molecular dynamics to calculate thermophysical properties, some data points deviate greatly from the preset conditions, and the accuracy of the calculated results after averaging is poor, especially under high temperature and high pressure conditions, the data fluctuates more violently, resulting in larger calculation errors and poorer accuracy. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present application proposes a method for calculating and correcting the thermophysical properties of single-component hydrocarbon fuels, which can correct and improve the preliminary calculation results of molecular dynamics and improve the accuracy and reliability of the calculation results.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A method for calculating and correcting the thermophysical properties of single-component hydrocarbon fuels.

[0008] Select a single-component hydrocarbon fuel to be analyzed, and input the operating parameters of the single-component hydrocarbon fuel to be analyzed; calculate the potential energy, heat flow in each direction, and stress fluctuation data of the molecular system of the single-component hydrocarbon fuel to be analyzed; and calculate the thermophysical properties of the single-component hydrocarbon fuel under the input operating parameters; the thermophysical properties include thermodynamic properties, energy properties, and transport properties; wherein the thermodynamic properties refer to density, the energy properties refer to internal energy, enthalpy, and entropy, and the transport properties refer to viscosity and thermal conductivity;

[0009] The thermophysical properties of the single-component hydrocarbon fuel under input conditions are corrected based on stability and kernel density estimation to obtain a thermophysical property data set. The intersection of each thermophysical property data set of the single-component hydrocarbon fuel under input conditions corrected based on stability and each thermophysical property data set of the single-component hydrocarbon fuel under input conditions corrected based on kernel density estimation is calculated, and the average value of the data in the intersection is taken as the corrected thermophysical property value.

[0010] Furthermore, based on the potential energy fluctuation data, the stable solution time corresponding to the thermodynamic properties and energy properties is determined according to the potential energy fluctuation in the hydrocarbon fuel molecular system; a data set corresponding to all the thermodynamic properties and energy properties under the input condition after the stable solution time is obtained; and a data set corresponding to all the density, internal energy, enthalpy and entropy under the input condition after the stable solution time is formed.

[0011] Furthermore, based on the fluctuation data of heat flux and stress in various directions, the stable solution moment corresponding to the transport properties is judged according to the fluctuation of heat flux and stress in various directions in the hydrocarbon fuel molecular system; wherein, the heat flux fluctuation corresponds to the thermal conductivity, and the stress fluctuation corresponds to the viscosity; and after the stable solution moment, a data set corresponding to all thermal conductivities and viscosities under the input working condition is formed.

[0012] Further, determine the stable solution time:

[0013] When the fluctuation amplitude of potential energy, heat flow and stress data gradually decreases and fluctuates slightly within a certain range, the starting moment of regular fluctuation of potential energy, heat flow and stress data within a certain range is identified as the stable solution moment.

[0014] Furthermore, the 2D kernel density method is used to draw the marginal kernel density probability distribution diagram of the temperature and pressure of hydrocarbon fuels, and the temperature and pressure ranges corresponding to the areas with dense operating points are taken as the operating fluctuation range of the thermophysical properties of single-component hydrocarbon fuels; the data sets corresponding to the thermodynamic properties, energy properties and transport properties within the operating fluctuation range are obtained, and the data sets corresponding to the density, internal energy, enthalpy, entropy, viscosity and thermal conductivity are obtained respectively.

[0015] Furthermore, the thermophysical properties of single-component hydrocarbon fuels under input operating parameters are calculated based on molecular dynamics and combined with thermophysical property calculation functions;

[0016] Furthermore, the thermophysical property calculation function includes a density calculation function, an internal energy calculation function, an enthalpy calculation function, an entropy calculation function, a viscosity calculation function and a thermal conductivity calculation function.

[0017] Furthermore, the viscosity calculation function and thermal conductivity calculation function are as follows:

[0018]

[0019]

[0020] In the formula, <*> represents the autocorrelation function, V and T represent the volume and temperature of the system respectively, and k B is the Boltzmann constant, P αβ (t) is the off-diagonal element of the system stress tensor, J(t) is the heat flux in the x, y, and z directions of the system, and t represents time.

[0021] Furthermore, the input conditions of the single-component hydrocarbon fuel to be analyzed include input temperature, input pressure and input molecular number.

[0022] Beneficial effects of the present invention:

[0023] This method corrects the thermophysical properties of single-component hydrocarbon fuels under input conditions through stability correction. Since stability correction is a standard for determining whether a molecular system has reached an equilibrium state through the fluctuation of some characterizing parameters to obtain stable thermophysical property data, through stability correction, some deviation data caused by system imbalance can be preferentially screened out, making subsequent thermophysical property calculation results more accurate and reliable.

[0024] The thermal properties of single-component hydrocarbon fuels under input conditions are corrected through kernel density estimation. Since the kernel density method does not use prior knowledge about data distribution and does not impose any assumptions on data distribution, it studies the data distribution characteristics from the data sample itself, which can effectively solve the shortcomings of traditional molecular dynamics when calculating the thermal properties of single-component hydrocarbon fuels, such as large operating condition fluctuations and low accuracy.

[0025] Finally, the data sets of various thermophysical properties of single-component hydrocarbon fuels under input conditions based on stability correction are intersected with the data sets of various thermophysical properties of single-component hydrocarbon fuels under input conditions based on kernel density estimation correction, and the average value of the data in the intersection is used as the corrected thermophysical property value; this can solve the problems of large errors, low accuracy, and large fluctuations in operating conditions when calculating thermophysical properties in traditional molecular dynamics. For the calculation of thermophysical properties of single-component hydrocarbon fuels under high temperature and pressure, it can better reduce the calculation error and improve the calculation accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a flow chart of a method for calculating and correcting the thermal properties of a single-component hydrocarbon fuel according to the present invention;

[0027] Figure 2 is a schematic diagram of the 2D kernel density method processing principle used in a specific embodiment of the present invention;

[0028] Figure 3 It is a comparison diagram of the thermal physical property errors of hydrocarbon fuels obtained by using the calculation correction method of the present invention in a specific embodiment of the present invention.

[0029] Figure 4 It is a density result cloud diagram obtained by using the calculation correction method of the present invention in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] Combined with Figure 1 The present invention proposes a method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel, which includes two parts: calculation and correction.

[0032] The calculation part includes:

[0033] S1. Select a certain single-component hydrocarbon fuel to be analyzed, and input the operating parameters of the single-component hydrocarbon fuel to be analyzed;

[0034] S2. Based on the potential function and the interaction between molecules, the potential energy, heat flow in all directions and stress fluctuation data of the single-component hydrocarbon fuel molecular system to be analyzed are calculated;

[0035] S3. Based on molecular dynamics and combined with the thermophysical property calculation function, the thermophysical properties of single-component hydrocarbon fuels under input operating parameters are preliminarily simulated and calculated;

[0036] Specifically, the thermophysical property calculation function includes a density calculation function, an internal energy calculation function, an enthalpy calculation function, an entropy calculation function, a viscosity calculation function and a thermal conductivity calculation function.

[0037] Thermophysical properties include thermodynamic properties, energy properties and transport properties; among them, thermodynamic properties refer to density, energy properties refer to internal energy, enthalpy and entropy, and transport properties refer to viscosity and thermal conductivity.

[0038] The input conditions of the single-component hydrocarbon fuel to be analyzed include input temperature, input pressure and input molecular number.

[0039] Among them, the calculation functions of viscosity and thermal conductivity are as follows:

[0040]

[0041]

[0042] In the formula, <*> represents the autocorrelation function, V and T represent the volume and temperature of the system respectively, and k B is the Boltzmann constant, P αβ (t) is the off-diagonal element of the system stress tensor, J(t) is the heat flux in the x, y, and z directions of the system, and t represents time.

[0043] Correction:

[0044] Includes stability correction and kernel density estimation correction;

[0045] 1. Stability correction refers to: correcting the thermal properties of single-component hydrocarbon fuels under input conditions based on stability (i.e., the six parameters of density, internal energy, enthalpy, entropy, viscosity, and thermal conductivity). Specifically:

[0046] 1.1. Based on the potential energy fluctuation data obtained in S2, the stable solution time corresponding to the thermodynamic properties and energy properties is determined according to the potential energy fluctuation in the hydrocarbon fuel molecular system; the data set corresponding to all the thermodynamic properties and energy properties under the input working condition after the stable solution time is obtained; thus, the data set corresponding to all the density, internal energy, enthalpy and entropy under the input working condition after the stable solution time is formed. Assume that the stable solution time is t 稳定 , then t 稳定 All density data after time is placed in the data set S 密度 =(s 密度1 、s 密度2 ,……,s 密度n ).

[0047] 1.2. Based on the fluctuation data of heat flux and stress in each direction obtained in S2, the stable solution time corresponding to the transport properties is determined according to the fluctuation of heat flux and stress in each direction in the hydrocarbon fuel molecular system; wherein, the heat flux fluctuation corresponds to the thermal conductivity, and the stress fluctuation corresponds to the viscosity; thus, a data set corresponding to all thermal conductivity and viscosity under the input working condition after the stable solution time is formed;

[0048] More specifically, since the potential energy, heat flow and stress data fluctuate greatly in the initial period of time, as time goes by, the single-component hydrocarbon fuel molecular system gradually tends to a state of equilibrium. Therefore, the fluctuations in the potential energy, heat flow and stress data will gradually become smaller and fluctuate slightly within a certain range. The starting moment when the potential energy, heat flow and stress data fluctuate regularly within a certain range is recognized as the stable solution moment.

[0049] 2. Kernel density estimation correction refers to correcting the thermophysical properties of single-component hydrocarbon fuels under input conditions based on kernel density estimation.

[0050] Specifically:

[0051] 2.1. The marginal kernel density probability distribution diagram of hydrocarbon fuel temperature and pressure is drawn using the 2D kernel density method. According to all operating points ( Figure 2 The distribution of the black dots in the marginal kernel density probability distribution diagram of , the temperature and pressure ranges corresponding to the areas with denser operating points are taken as the operating fluctuation ranges of the thermophysical properties of single-component hydrocarbon fuels;

[0052] 2.2. Obtain the data sets corresponding to the thermodynamic properties, energy properties and transport properties within the fluctuation range of the working condition, that is, obtain the data sets corresponding to density, internal energy, enthalpy, entropy, viscosity and thermal conductivity. Taking density data as an example, within the fluctuation range of the working condition, all density data are placed in the data set S 密度 ′=(s 密度1 ′、s 密度2 ′,......,s 密度n ′).

[0053] 3. For each type of thermophysical property data, take the intersection of the data set after stability correction and the data set after kernel density estimation correction; and calculate the average value of all data in the intersection, and use the average value as the corrected thermophysical property value.

[0054] In this application, the data sets corresponding to density, internal energy, enthalpy, entropy, thermal conductivity, and viscosity obtained by stability correction are respectively represented by S 密度 , S 内能 , S 焓 , S 熵 , S 导热系数 , S 黏度 Represented by; then suppose that the final data set obtained by kernel density estimation correction is density, internal energy, enthalpy, entropy, thermal conductivity, and viscosity, respectively, and S 密度 '、S 内能 ′、S 焓 ′、S 熵 ′、S 导热系数 '、S 黏度 'express.

[0055] Taking density as an example, take S 密度 With S 密度 ', and average the density data in the intersection, and use the average value as the corrected density value. Similarly, the same treatment is performed on internal energy, enthalpy, entropy, thermal conductivity, and viscosity.

[0056] In order to more clearly illustrate the technical solution of the present application, n-dodecane is used for illustration in this embodiment.

[0057] The input operating parameters of n-dodecane are: temperature range is 0-2000K, pressure range is 0-3000atm, and the number of molecules is 3000.

[0058] The thermophysical property calculation function of n-dodecane is as follows:

[0059] The density calculation function is the ratio of the mass to volume of the n-dodecane molecular system;

[0060] The calculation function of viscosity and thermal conductivity is the Green-Kubo equilibrium formula;

[0061] The internal energy calculation function is the sum of the kinetic energy and potential energy of the n-dodecane molecular system. The system kinetic energy is the sum of the kinetic energy of each n-dodecane molecule, and the system potential energy is the product of the sum of various potential energy functions of each molecule and the number of molecules.

[0062] The enthalpy calculation function is the sum of the product of the system volume and pressure plus the internal energy;

[0063] The entropy calculation function is the ratio of internal energy to the system temperature.

[0064] The molecular dynamics method was used to perform preliminary simulations using the LAMMPS open source software (Large-scale Atomic / Molecular Massively Parallel Simulator). The initial model was constructed using the Packmol open source software to build a cubic model; the initial density was set to the liquid phase density of 0.761 g / cm 3 The isothermal and isobaric (NPT) ensemble was used for relaxation and calculation. The temperature and pressure were controlled by Nose-Hoover. The boundary conditions during the simulation were periodic boundary conditions. In order to make the system density consistent with the actual value and avoid the particle spacing being too small or overlapping, the initial velocity of all particles was set to conform to the Maxwell-Boltzmann distribution as a whole. The force field model was the SKS united atom force field model; the intramolecular non-bonded potential and intermolecular interaction force were Lennard-Jones 12-6 potential, and the cutoff radius was The particle interactions beyond the cutoff radius are set to zero by default; the bond stretching and bond angle bending potentials use the harmonic potential; the dihedral angle torsion potential uses the OPLS potential. The LJ potential function parameters for different types of particle interactions use the Arithmetic mixing rule. The system relaxation time is 1ns and the calculation time is 4ns.

[0065] After the preliminary calculation of molecular dynamics simulation is completed, the preliminary calculated values ​​of the thermodynamic properties, energy properties, and transport properties of n-dodecane are output.

[0066] Furthermore, the stability of the parameters is corrected through the potential energy, heat flow and stress fluctuations of the n-dodecane molecular system, and the kernel density estimation of the parameters is corrected through the distribution of the system's operating point data in the marginal kernel density probability distribution diagram.

[0067] The results of the fluctuation of the potential energy of the n-dodecane molecular system show that the potential energy of the system enters a stable state after the system relaxation is completed. Therefore, the relevant thermodynamic properties (density, internal energy, enthalpy and entropy) are taken as the stability correction data after the data point 1ns after the system relaxation is completed. According to the fluctuation of the heat flow in the three directions x, y and z of the n-dodecane system, the data after the shortest convergence time when the heat flow in the three directions x, y and z tends to zero are taken as the stability correction data of the thermal conductivity. According to the fluctuation of the non-diagonal elements of the system stress tensor, namely Pxy, Pyz and Pzx, the data after the shortest convergence time when the three stresses tend to zero are taken as the stability correction data of the viscosity.

[0068] Through the above stability correction, the stability correction data of all thermodynamic properties and energy properties under a certain input condition after the stable solution moment are obtained, that is, a data set corresponding to all density, internal energy, enthalpy and entropy under a certain input condition after the stable solution moment is formed.

[0069] Under any input operating point, there are a lot of thermophysical property data points of single-component hydrocarbon fuels, and some data points deviate greatly from the preset operating conditions. The accuracy of the calculated results after averaging is poor, especially under high temperature and high pressure conditions. Therefore, it is necessary to use kernel density estimation to make relevant corrections to the input operating point range.

[0070] like Figure 2 As shown in the figure, the marginal kernel density probability distribution diagram of the input temperature and input pressure data points is drawn. The bandwidth method of the two-dimensional kernel density diagram is set as the kernel density estimation of the two variables. The density method adopts the precise estimation method and interpolates the density of the data points. The probability distribution curve is obtained by smoothing with Kernel Smooth. The data points within the temperature and pressure range where the kernel is located in the kernel density diagram or the data points near the peak value in the probability distribution curve are taken as valid operating condition data points to obtain the accurate and effective operating condition fluctuation range after correction by the kernel density estimation.

[0071] like Figure 3 As shown, it is a density error comparison diagram of single-component hydrocarbon fuel obtained by the calculation correction method of the present invention under high temperature conditions of 264K to 650K. The square points are the density result diagram of n-dodecane without kernel density estimation processing, the circular points are the result diagram using kernel density estimation processing, and the triangle points are the experimental values ​​of the NIST database. It can be found that the density calculation results of single-component hydrocarbon fuel processed by kernel density estimation are closer to the NIST experimental values. Compared with the preliminary calculated values, the calculation error is smaller and the results are more accurate, which is more obvious under the high temperature condition of 650K.

[0072] The intersection of the corrected data points obtained by the stability correction and kernel density estimation correction is taken, and the weighted average is taken to obtain the thermodynamic properties, energy properties and transport properties of n-dodecane under the input conditions. Figure 4 As shown, it is a density result cloud diagram of n-dodecane under 0-2000K, 0-3000atm conditions obtained by the method of the present invention. It can be found that the calculation correction method of the present invention has the ability to reliably predict the thermal properties of single-component hydrocarbon fuels.

[0073] The present invention proposes a method for calculating and correcting the thermophysical properties of single-component hydrocarbon fuels, which can solve the problems of large fluctuations in the working conditions of traditional molecular dynamics properties, low calculation accuracy, and large errors. For the calculation of the thermophysical properties of single-component hydrocarbon fuels under high temperature and high pressure, it can better reduce the calculation error, improve the calculation accuracy, and achieve the purpose of accurately and reliably predicting and calculating the thermophysical properties of hydrocarbon fuels under different working conditions, which well meets the new standards and high requirements for the working range of fuels under the background of "dual carbon" today.

[0074] The above embodiments are only used to illustrate the design ideas and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The protection scope of the present invention is not limited to the above embodiments. Therefore, any equivalent changes or modifications made based on the principles and design ideas disclosed by the present invention are within the protection scope of the present invention.

Claims

1. A method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel, characterized in that: Select a single-component hydrocarbon fuel to be analyzed, and input the operating parameters of the single-component hydrocarbon fuel to be analyzed; calculate the potential energy, heat flow in each direction, and stress fluctuation data of the molecular system of the single-component hydrocarbon fuel to be analyzed; and calculate the thermophysical properties of the single-component hydrocarbon fuel under the input operating parameters; the thermophysical properties include thermodynamic properties, energy properties, and transport properties; wherein the thermodynamic properties refer to density, the energy properties refer to internal energy, enthalpy, and entropy, and the transport properties refer to viscosity and thermal conductivity; The thermophysical properties of the single-component hydrocarbon fuel under input conditions are corrected based on stability and kernel density estimation to obtain a thermophysical property data set. The intersection of each thermophysical property data set of the single-component hydrocarbon fuel under input conditions corrected based on stability and each thermophysical property data set of the single-component hydrocarbon fuel under input conditions corrected based on kernel density estimation is calculated, and the average value of the data in the intersection is taken as the corrected thermophysical property value.

2. A method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel according to claim 1, characterized in that: Based on the potential energy fluctuation data, the stable solution time corresponding to the thermodynamic properties and energy properties is determined according to the potential energy fluctuation in the hydrocarbon fuel molecular system; the data set corresponding to all the thermodynamic properties and energy properties under the input condition after the stable solution time is obtained; and the data set corresponding to all the density, internal energy, enthalpy and entropy under the input condition after the stable solution time is formed.

3. A method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel according to claim 1, characterized in that: Based on the fluctuation data of heat flux and stress in various directions, the stable solution moment corresponding to the transport properties is determined according to the fluctuation of heat flux and stress in various directions in the hydrocarbon fuel molecular system; among which, the heat flux fluctuation corresponds to the thermal conductivity, and the stress fluctuation corresponds to the viscosity; after the stable solution moment, a data set corresponding to all thermal conductivities and viscosities under the input working condition is formed.

4. A method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel according to claim 2 or 3, characterized in that: Determine the time when the solution is stable: When the fluctuation amplitude of potential energy, heat flow and stress data gradually decreases and fluctuates slightly within a certain range, the starting moment of regular fluctuation of potential energy, heat flow and stress data within a certain range is identified as the stable solution moment.

5. A method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel according to claim 2 or 3, characterized in that: The 2D kernel density method is used to draw the marginal kernel density probability distribution diagram of the temperature and pressure of hydrocarbon fuels, and the temperature and pressure ranges corresponding to the areas with dense operating points are taken as the operating fluctuation range of the thermophysical properties of single-component hydrocarbon fuels. The data sets corresponding to the thermodynamic properties, energy properties and transport properties within the operating fluctuation range are obtained, and the data sets corresponding to the density, internal energy, enthalpy, entropy, viscosity and thermal conductivity are obtained respectively.

6. A method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel according to claim 1, characterized in that: Based on molecular dynamics and combined with the thermophysical property calculation function, the thermophysical properties of single-component hydrocarbon fuels under input operating parameters are calculated.

7. A method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel according to claim 6, characterized in that: Thermophysical property calculation functions include density calculation function, internal energy calculation function, enthalpy calculation function, entropy calculation function, viscosity calculation function and thermal conductivity calculation function.

8. A method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel according to claim 7, characterized in that: The viscosity calculation function and thermal conductivity calculation function are as follows: In the formula, <*> represents the autocorrelation function, V and T represent the volume and temperature of the system respectively, and k B is the Boltzmann constant, P αβ (t) is the non-diagonal element of the system stress tensor, J(t) is the heat flux in the x, y, and z directions of the system, and t represents time.

9. A method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel according to claim 7, characterized in that: The density calculation function is the ratio of the mass to volume of the single-component hydrocarbon fuel system to be analyzed; The internal energy calculation function is the sum of the kinetic energy and potential energy of the single-component hydrocarbon fuel system to be analyzed; The enthalpy calculation function is the sum of the product of the system volume and pressure plus the internal energy; The entropy calculation function is the ratio of internal energy to the temperature of the system.

10. A method for calculating and correcting the thermophysical properties of a single-component hydrocarbon fuel according to claim 1, characterized in that: The input conditions of the single-component hydrocarbon fuel to be analyzed include input temperature, input pressure and input molecular number.

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