A method for checking test data of a high-speed diesel engine based on a quasi-dimensional combustion model

Abstract

The present invention discloses a method for verifying test data of a high-speed diesel engine based on a quasi-dimensional combustion model, belonging to the technical field of internal combustion engines. The method includes: S1, establishing an overall engine model; S2, selecting an in-cylinder combustion model and adjusting combustion parameters; S3, comparing the simulation data obtained from model simulation with the existing test data to judge the accuracy of the model. If the requirements are not met, use DIWiebe to establish an in-cylinder combustion model and use its simulation data to adjust the combustion parameters of the model; S4, comparing the simulation data obtained from the adjusted model simulation with the existing test data to judge the accuracy of the model; if the accuracy requirements are met, proceed to S5; otherwise, use TPA to establish an in-cylinder combustion model and adjust the combustion parameters of the model; S5, using the obtained model to verify the test data. The present invention can evaluate the accuracy of test data, without the need to repeat the process of the overall engine test multiple times, and greatly saves the R & D cost of diesel engines.

Description

Technical Field

[0001] The present invention belongs to the technical field of internal combustion engines, and particularly relates to a method for checking test data of a high-speed diesel engine based on a quasi-dimensional combustion model. Background Art

[0002] The accuracy of diesel engine test data directly determines the accuracy of one-dimensional simulation of diesel engines. Excessive errors in test data may even lead to results where the model simulation completely deviates from the test data. Therefore, the accuracy of test data is crucial for one-dimensional simulation. However, the methods for checking test data are basically to correct through multiple whole-engine tests of diesel engines, and there is no way at the simulation level to verify the test data.

[0003] Although re-testing the whole diesel engine can obtain more accurate test data and correct the error data to the greatest extent. However, the whole-engine test not only has a long time cycle but also high test costs, resulting in waste of manpower and material resources and increasing the R & D cost of diesel engines. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems in the above related technologies to some extent.

[0005] Therefore, the purpose of the present invention is to provide a method for checking test data of a high-speed diesel engine based on a quasi-dimensional combustion model, which can evaluate the accuracy of test data, without the need to repeat the whole-engine test process multiple times, and greatly saves the R & D cost of diesel engines.

[0006] To solve the above technical problems, the present invention is implemented as follows:

[0007] The embodiment of the present invention provides a method for checking test data of a high-speed diesel engine based on a quasi-dimensional combustion model, and the method includes:

[0008] S1. Adopt the GT-POWER combustion model, and establish a first whole-diesel-engine model based on the existing whole-diesel-engine test data;

[0009] S2. Select an in-cylinder combustion model based on the existing test cylinder pressure data and heat release rate curve data, and adjust the combustion parameters of the selected combustion model to obtain a first in-cylinder combustion model;

[0010] S3. Compare the simulation data obtained from the simulation of the first whole-diesel-engine model and the first in-cylinder combustion model with the existing test data to judge the accuracy of the first in-cylinder combustion model. When the accuracy requirement is not met, use the DIWiebe combustion model to establish an in-cylinder combustion model and use the simulation data of this model to adjust the combustion parameters of the first in-cylinder combustion model to obtain a second in-cylinder combustion model;

[0011] S4. Compare the simulation data obtained from the combustion model simulation of the second cylinder with the existing test data to determine the accuracy of the combustion model of the second cylinder. If the accuracy requirement is met, proceed to S5; otherwise, use TPA to establish an in-cylinder combustion model and adjust the combustion parameters of the combustion model of the second cylinder with the simulation data of this model to obtain the combustion model of the third cylinder.

[0012] S5. Adopt the constructed first diesel engine whole-machine model and the obtained in-cylinder combustion model simulation data, and check the test data.

[0013] In addition, according to the method for checking test data of a high-speed diesel engine based on a quasi-dimensional combustion model of the present invention, the following additional technical features may also be provided:

[0014] In some of the embodiments, the content of step S2 includes:

[0015] Solve the average value of the test data of the heat release rate for multiple cycles to obtain the average heat release rate.

[0016] Perform FFT filtering on the average heat release rate.

[0017] Calibrate and adjust the combustion parameters of the selected combustion model based on the filtered data to obtain the combustion model of the first cylinder.

[0018] In some of the embodiments, the content of step S3 includes:

[0019] Obtain the cylinder pressure curve and the heat release rate curve through simulation by the combustion model of the first cylinder.

[0020] Check the simulated cylinder pressure curve and the existing test cylinder pressure curve, and the simulated heat release rate curve and the existing test heat release rate curve, and determine whether the respective degrees of coincidence of the cylinder pressure curve and the heat release rate curve meet the requirements. If both meet the requirements, proceed to the next step; otherwise, re-check the cylinder pressure curve and the heat release rate curve of the model.

[0021] Compare the simulated whole-machine parameters with the existing test whole-machine parameters to determine the difference between the two. When the difference in the whole-machine parameters is greater than the preset judgment threshold, it is determined that the accuracy of the combustion model of the first cylinder does not meet the requirements; otherwise, it meets the requirements.

[0022] In some of the embodiments, the whole-machine parameters for comparison include the exhaust temperature, and the judgment threshold for the exhaust temperature is 15°.

[0023] In some of the embodiments, the data of the heat release rate curve is obtained by calculating the measured cylinder pressure data through a heat transfer model.

[0024] In some of these embodiments, the first whole diesel engine model includes models of the intake and exhaust system, fuel injection system, intercooling system, supercharging system, and cylinder system.

[0025] In some of these embodiments, adjusting the combustion parameters of the selected combustion model in step S2 includes synchronously adjusting the fuel injection timing and the combustion start timing.

[0026] In some of these embodiments, when comparing the simulation data with the existing test data in step S3 and comparing the heat release rate curves, the comparison parameters include timing, trend, and value.

[0027] In some of these embodiments, the content of using TPA to establish an in-cylinder combustion model in step S4 and using the simulation data of this model to adjust the combustion parameters of the second in-cylinder combustion model includes:

[0028] Comparing whether the cut-off time of the simulated heat release rate of the in-cylinder combustion model of TPA is consistent with that of the in-cylinder combustion model of DIWiebe; if so, proceed to the next step, otherwise, re-check the cylinder pressure curve of the in-cylinder combustion model of DIWiebe;

[0029] Comparing whether the peak value of the simulated heat release rate data of the in-cylinder combustion model of TPA is consistent with the peak value of the test heat release rate data; if so, it is determined that there is only a problem of incomplete test heat release rate data; otherwise, it is determined that there is a post-combustion phenomenon caused by abnormal fuel injection;

[0030] Adjust the combustion parameters of the second in-cylinder combustion model according to the determination result.

[0031] An embodiment of the present invention also provides a high-speed diesel engine test data verification device based on a quasi-dimensional combustion model, including a processor, a memory, and a software program stored on the memory. When the software program runs on the processor, it can implement the steps of the high-speed diesel engine test data verification method based on a quasi-dimensional combustion model described in any one of the above.

[0032] Compared with the prior art, the present invention has at least the following beneficial effects:

[0033] In the embodiment of the present invention, the provided high-speed diesel engine test data verification method based on a quasi-dimensional combustion model can judge the accuracy of the heat release rate heat transfer model calculated by the test cylinder pressure during the diesel engine test stage, improve the accuracy of simulation calculation during the diesel engine test stage, and clarify whether the current in-cylinder combustion state of the diesel engine meets the exhaust temperature requirement index;

[0034] In the embodiment of the present invention, the provided high-speed diesel engine test data verification method based on a quasi-dimensional combustion model can evaluate the accuracy of test data, without repeatedly performing the test process, which greatly saves the R & D cost of diesel engines;

[0035] In the embodiment of the present invention, the provided method for verifying test data of a high-speed diesel engine based on a quasi-dimensional combustion model can improve the accuracy of simulation by providing accurate test data, provide an accurate in-cylinder combustion model for subsequent work such as optimizing the overall performance of the diesel engine, the fuel injection system, and the supercharging system, and facilitate the improvement of the overall performance of the diesel engine at the theoretical level;

[0036] In the embodiment of the present invention, the provided method for verifying test data of a high-speed diesel engine based on a quasi-dimensional combustion model is applicable to verifying the parameters of the heat transfer model and analyzing the accuracy of the heat release rate data during the overall engine test of the diesel engine, ensuring the accuracy of the in-cylinder combustion process, improving the accuracy of one-dimensional simulation, and laying a foundation for the overall performance simulation of the diesel engine.

[0037] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings

[0038] Figure 1 Flow chart for verifying test data based on the GT-POWER diesel engine overall model disclosed in an embodiment of the present invention;

[0039] Figure 2 Flow chart for verifying test data with different quasi-dimensional combustion models disclosed in an embodiment of the present invention;

[0040] Figure 3 Graph showing the verification results of cylinder pressure and heat release rate for the in-cylinder combustion process of heat release rate modeling disclosed in an embodiment of the present invention;

[0041] Figure 4 Flow chart for modeling in-cylinder combustion with the DIWiebe combustion model disclosed in an embodiment of the present invention;

[0042] Figure 5 Graph showing the verification results of cylinder pressure and heat release rate for the in-cylinder combustion process of modeling with the DIWiebe combustion model disclosed in an embodiment of the present invention;

[0043] Figure 6 Flow chart for modeling in-cylinder combustion with the TPA disclosed in an embodiment of the present invention;

[0044] Figure 7 Graph showing the verification results of cylinder pressure and heat release rate for the in-cylinder combustion of modeling with the TPA disclosed in an embodiment of the present invention. Detailed Embodiments

[0045] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts belong to the scope of protection of the present invention.

[0046] Next, in combination with the accompanying drawings, the embodiments of the present invention will be described in detail through specific embodiments and their application scenarios.

[0047] In some embodiments of the present invention, a method for verifying high-speed diesel engine test data based on a quasi-dimensional combustion model is provided. Using one-dimensional simulation software GT-POWER, a quasi-dimensional combustion is used to establish the in-cylinder combustion process. By verifying the cylinder pressure and heat release rate curves and comparing the simulation and test data, the accuracy of the test data is determined; based on the accurate comparison results, the problems existing in the whole engine test are analyzed, the problems existing in the whole engine test process of the diesel engine are clarified, providing an optimization direction for subsequent tests for enterprises, saving the R & D cost of the diesel engine, and improving the test efficiency.

[0048] In some embodiments of the present invention, during the verification process of the GT-POWER diesel engine whole engine model, please refer to Figure 1 As shown, using the GT-POWER combustion model, based on the test data of a certain diesel engine whole engine, models of diesel engine subsystems such as the intake and exhaust system, fuel injection system, intercooling system, supercharging system, and cylinder system are established. The key parameters of the subsystem models are calibrated with reference to the test data of a certain diesel engine. After the above parameter calibration is completed, an in-cylinder combustion model is selected based on the test cylinder pressure and heat release rate curves. Based on the test cylinder pressure and heat release rate data, the parameters of the in-cylinder combustion model are adjusted to ensure that the simulation cylinder pressure and heat release rate results are consistent with the test cylinder pressure and heat release rate results. Specifically: calibrate the in-cylinder combustion model with the test heat release rate curve and calibrate the in-cylinder combustion model with the test cylinder pressure data; after calibration, verify the cylinder pressure and heat release rate curves of the simulation and the test. After the cylinder pressure and heat release rate curves are verified, if there are deviations within the allowable error range for the remaining parameters, it proves that the model simulation can simulate the in-cylinder combustion process of the diesel engine whole engine test. Calibration refers to importing the real data collected from the test, such as cylinder pressure and heat release data, into the model. When calibrating a certain parameter, other parameters of the combustion model do not need to be set; verification and calibration refer to comparing the simulation data with the test data to judge the degree of similarity. Based on the above modeling and calibration process, a discussion on a method for verifying high-speed diesel engine test data based on a quasi-dimensional combustion model described in the present invention is carried out. When the cylinder pressure and heat release rate curves meet the requirements, but the remaining parameters exceed the allowable error range, the parameters of the in-cylinder combustion model need to be adjusted. The parameters of the in-cylinder combustion model can be adjusted based on the DIWiebe combustion model and the TPA combustion model in sequence.

[0049] For the calibration test data of different quasi-dimensional combustion models, please refer to Figure 2 As shown, first, the heat release rate test data of multiple cycles are averaged, and the average heat release rate is Fourier filtered (FFT filtering) to obtain smooth heat release rate curve data for calibrating the in-cylinder combustion model. After calibrating the in-cylinder combustion model using the test heat release rate data, the injector setting parameters will no longer affect the simulation results at this time. Only the injection timing and the combustion start time two parameters will affect the simulation results. Therefore, adjust the injection timing and the combustion start time two parameters; after the adjustment is completed, simulate and calibrate the simulated and test cylinder pressure curves, and compare the coincidence degree of the simulated and test heat release rate curves. The heat release rate curve is calculated by the heat transfer model from the measured cylinder pressure in the test. In theory, the cylinder pressure and heat release amount curves calculated by simulating and calibrating the cylinder combustion model with the heat release rate curve should completely coincide with the cylinder pressure and heat release rate curves obtained from the test. When comparing the heat release amount curves, the timing, trend, and important values can be focused on; when the comparison of the cylinder pressure curve and the heat release rate curve both meet the requirements, it means that the above model meets the requirements and can be used to calibrate the subsequent test data. After comparing the cylinder pressure and heat release rate curves, compare the overall engine parameters, such as the exhaust temperature, boost pressure, intake air flow, etc. The simulation results of the overall engine parameters should theoretically be basically consistent with the test results. However, from the simulation results, after the cylinder pressure curve calibration is completed, the simulated heat release rate curve is significantly higher than the test heat release rate curve, please refer to Figure 3 As shown, and the exhaust temperature is much lower than the test data. Specifically, the simulated exhaust temperature in front of the turbine is much lower than the test exhaust temperature. This result proves that there are large errors in the test heat release rate data and need to be inspected and calibrated.

[0050] In some embodiments of the present invention, please refer to Figure 4 As shown, the process of modeling in-cylinder combustion with the DIWiebe combustion model includes: first, select the DIWiebe combustion model to establish the in-cylinder combustion process, and according to its simulated heat release rate data, replace the test heat release rate data to calibrate the in-cylinder combustion and realize the adjustment of the combustion model parameters. Calibrate the cylinder pressure curves under simulation and test, then compare the end time and peak value data of the heat release rate curves under simulation and test, and finally compare the exhaust temperature data under simulation and test.

[0051] In this embodiment, please refer to Figure 5As shown, the cylinder pressure curve of the DIWiebe combustion model is in good agreement. The simulated heat release rate curve can basically match the experimental heat release rate curve. The simulated heat release duration is significantly longer than the experimental heat release duration, and the simulated heat release rate curve is significantly wider than the experimental heat release rate curve, that is, the simulated in-cylinder combustion heat release is higher than the experimental heat release. The simulated heat release rate naturally ends at 140deg, while the experimental heat release rate curve ends at 90deg cut-off. The DIWiebe combustion model proves that there is a phenomenon of missing experimental heat release rate data. At the 90deg position of the experimental heat release rate curve, the heat release rate does not naturally drop to 0, but shows a cut-off to 0. This is very likely because 90deg is set as the cut-off time when calculating the heat release rate from the experimental cylinder pressure. Therefore, using the experimental heat release rate data to calibrate the in-cylinder combustion process is the reason why the simulated exhaust temperature is significantly lower than the experimental value even after the cylinder pressure curve is calibrated and matched.

[0052] The test results are as follows: When the other parameters of the DIWiebe combustion model are basically in agreement with the experimental data, the simulated exhaust temperature in front of the turbine is 48°C lower than the experimental exhaust temperature in front of the turbine, with a non-negligible deviation. This shows that the heat release rate curve calculated by the DIWiebe combustion model can only prove the phenomenon of early truncation of the experimental heat release rate curve, and cannot prove when the actual heat release rate curve is truncated. And on the premise that the cylinder pressure curves are almost completely consistent after calibration, the simulated heat release rate curve is significantly wider than the experimental heat release rate curve, but the simulated exhaust temperature in front of the turbine is significantly lower than the experimental exhaust temperature, which is contrary to the theory. That is to say, the time when the experimental heat release rate returns to 0 is higher than 140deg or the heat release rate obtained by experimental measurement is much lower than the actual in-cylinder combustion situation. This is because the heat release rate curve is directly measured from the actual cylinder pressure curve. After other systems are calibrated correctly, the above contradictions are speculated to be caused by abnormal fuel injection, resulting in obvious afterburning in the cylinder or even combustion in the exhaust passage. Therefore, in the experiment, the combustion analyzer can only collect the heat released by the combustion of the fuel in the cylinder and cannot collect the heat released by the combustion of the fuel entering the exhaust passage. Therefore, it is necessary to replace the combustion model and recalculate the heat release rate.

[0053] In some embodiments of the present invention, the experimental cylinder pressure data is used to model the in-cylinder combustion, also known as TPA calibration of in-cylinder combustion. The heat release rate curve is obtained based on the cylinder pressure curve and the law of conservation of energy. If there is combustion in the exhaust passage, the combustion heat release rate curve will be significantly lower. The experimental cylinder pressure curve can most directly display the in-cylinder combustion process. Therefore, the present invention attempts to directly use the experimental cylinder data (TPA) to model the in-cylinder combustion process. In the method of modeling the in-cylinder combustion model based on the experimental cylinder pressure data, the cylinder pressure curve is directly measured by the experiment, and the heat release rate curve is obtained by analyzing the in-cylinder heat transfer model. Therefore, the cylinder pressure curve is the experimental parameter closest to the real process of the diesel engine. The average value of the experimental cylinder pressure curves of multiple cycles is calculated, and FFT smoothing filtering is performed based on the average cylinder pressure to obtain the cylinder pressure curve for modeling the combustion process.

[0054] In this embodiment, please refer to Figure 6 As shown, the process of TPA modeling of in-cylinder combustion includes: first, averaging the cylinder pressure test data of multiple cycles; performing FFT filtering on the averaged cylinder pressure; calibrating the in-cylinder combustion model (TPA) with the filtered cylinder pressure data; then adjusting the injection timing; proofreading the simulation and test cylinder pressure curves to ensure that the simulation combustion start time is consistent with the test; then comparing whether the heat release rate curves obtained by TPA simulation and the test heat release rate curves are consistent. If they are consistent, check the verification of the overall engine parameters. If they are not consistent, it is necessary to adjust the parameters of the cylinder heat transfer model, mainly the piston convective heat transfer coefficient, the cylinder convective heat transfer coefficient, and the valve convective heat transfer coefficient. At this time, compare with the overall engine characteristic parameters: power, torque, fuel consumption rate, explosion pressure, temperature before intercooler, pressure after intercooler, exhaust gas temperature before and after the turbine, etc. If all the overall engine parameters are verified correctly and the simulation cylinder pressure curve and the heat release rate curve are both consistent with the test, it means that the cylinder pressure and heat release rate data obtained during the test are correct. If the cylinder pressure curve is verified correctly, the simulation heat release rate curve is significantly higher than the test heat release rate curve, and among the overall engine parameters, the simulation exhaust gas temperature before and after the turbine is significantly lower than the test exhaust gas temperature, it means that there is an extreme afterburning phenomenon, mainly the combustion situation in the exhaust passage.

[0055] Please refer to Figure 7 As shown, the cylinder pressure simulation results of the TPA modeling in-cylinder combustion model are completely consistent with the test results. The peak value of the heat release rate is significantly higher than the peak value of the test heat release rate, and there is also the same situation of ending heat release at 140deg as in the modeling combustion of the DI Wiebe combustion model. This confirms the extreme combustion situation caused by abnormal fuel injection during the test - combustion in the exhaust passage. The default setting of the cycle fuel quantity in the GT-POWER software simulation is the ideal situation of in-cylinder combustion. TPA is calibrated as the most accurate display of the test combustion process. After the overall engine parameters are verified correctly, there is still a situation where the test heat release rate curve is low and the simulation exhaust gas temperature is significantly low, which proves the occurrence of extreme combustion in the exhaust passage. At the same time, since the TPA modeling of in-cylinder combustion is theoretically the most accurate in-cylinder combustion modeling method, and there is an obvious phenomenon of late heat release behind the heat release rate curve obtained by the TPA method, it can be confirmed that there is an early truncation phenomenon in the test heat release rate curve.

[0056] From the comparative analysis of the above different in-cylinder modeling processes, it can be seen that after obtaining the test cylinder pressure and heat release rate curves, the in-cylinder combustion model can be established in the following order to verify whether the test curves are accurate.

[0057] (1)Modeling in-cylinder combustion with experimental heat release rate data. If, after accurate verification of the cylinder pressure curve, the simulation of various parameters of the entire diesel engine is basically consistent with the experiment, it can be considered that the cylinder pressure and heat release rate curves obtained from the experiment are accurate. If, after accurate verification of the cylinder pressure curve, there are significant deviations between the simulation results of parameters such as exhaust temperature and the experimental results, it indicates that there are significant errors in the experimental heat release rate curve, and the deviations are mainly concentrated in the heat transfer parameters of the heat release rate model and the cut-off time for calculating the heat release rate.

[0058] (2)Modeling in-cylinder combustion with the DI Wiebe combustion model. Adjust the DI Wiebe combustion parameters and verify the cylinder pressure curve. After the verification of the cylinder pressure curve is completed, compare the simulation and experimental heat release rate curves. Analyze the cut-off position of the heat release rate curve. If the crankshaft angles corresponding to the cut-off of the simulation and experimental heat release rates are basically the same, it indicates that the cut-off time of the experimental heat release rate is correct; if there are significant deviations, it indicates that the cut-off time is incorrect and TPA cylinder pressure calibration needs to be used for further calculation. After the verification of the cut-off time of the heat release rate is completed, compare other parameters such as the simulation and experimental exhaust temperatures. If the simulated exhaust temperature is significantly lower than the experimental exhaust temperature but the simulated heat release rate curve is higher than the experimental heat release rate curve, it indicates a serious afterburning phenomenon.

[0059] (3)Modeling in-cylinder combustion with experimental cylinder pressure data (TPA). The experimental cylinder pressure data is the data closest to the in-cylinder combustion during the diesel engine experiment. Therefore, the heat release rate obtained by calculating the in-cylinder combustion process through TPA calibration is the most accurate heat release rate data. At this time, compare the simulation and experimental heat release rate data. If the cut-off position of the heat release rate calculated by the DI Wiebe combustion model is the same as the cut-off position obtained from the experiment, it proves that the cut-off position of the heat release rate curve calculated by the DI Wiebe combustion model is accurate. At this time, compare the heat release rate value calculated by TPA with the experimental heat release rate value and the parameters of the entire engine. If they are basically the same, it can be considered that the experimental data is correct; if there are significant deviations between the heat release rate value calculated by TPA and the experimental heat release rate value, there are obvious abnormalities in the experimental combustion process, and the actual heat release rate should be based on the heat release rate calculated by TPA calibration.

[0060] For the parts not described in detail in the present invention, reference can be made to the existing technologies in the field or the technologies well-known to those skilled in the art.

[0061] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the purpose of the present invention and the scope protected by the claims, and all of them fall within the protection scope of the present invention.

Claims

1. A method for verifying test data of a high-speed diesel engine based on a quasi-dimensional combustion model, characterized in that, The method includes: S1. Using the GT-POWER combustion model, based on the existing diesel engine overall test data, establish the first diesel engine overall model; S2. Based on the existing test cylinder pressure data and heat release rate curve data, select the in-cylinder combustion model, and adjust the combustion parameters of the selected combustion model to obtain the first in-cylinder combustion model; S3. Compare the simulation data obtained from the first diesel engine overall model and the first in-cylinder combustion model with the existing test data to judge the accuracy of the first in-cylinder combustion model. When the accuracy requirement is not met, use the DIWiebe combustion model to establish the in-cylinder combustion model and use the simulation data of this model to adjust the combustion parameters of the first in-cylinder combustion model to obtain the second in-cylinder combustion model; S4. Compare the simulation data obtained from the second in-cylinder combustion model with the existing test data to judge the accuracy of the second in-cylinder combustion model; if the accuracy requirement is met, enter S5; otherwise, use TPA to establish the in-cylinder combustion model and use the simulation data of this model to adjust the combustion parameters of the second in-cylinder combustion model to obtain the third in-cylinder combustion model; S5. Adopt the constructed first diesel engine overall model and the obtained in-cylinder combustion model simulation data, and check the test data; The content of step S2 includes: Solve the average value of the multiple-cycle heat release rate test data to obtain the average heat release rate; Perform FFT filtering on the average heat release rate; Based on the filtered data, calibrate and adjust the combustion parameters of the selected combustion model to obtain the first in-cylinder combustion model; The content of step S3 includes: Obtain the cylinder pressure curve and heat release rate curve by simulating the first in-cylinder combustion model; Compare the simulated cylinder pressure curve with the existing test cylinder pressure curve, and the simulated heat release rate curve with the existing test heat release rate curve, and judge whether the respective fitting degrees of the cylinder pressure curve and the heat release rate curve meet the requirements. If both meet the requirements, enter the next step; otherwise, re-check the cylinder pressure curve and heat release rate curve of the model; Compare the simulated overall engine parameters with the existing test overall engine parameters, and judge the difference between the two; when the difference of the overall engine parameters is greater than the preset judgment threshold, it is determined that the accuracy of the first in-cylinder combustion model does not meet the requirements, otherwise it meets the requirements; The content of using TPA to establish the in-cylinder combustion model and using the simulation data of this model to adjust the combustion parameters of the second in-cylinder combustion model in step S4 includes: Compare whether the simulation heat release rate cut-off time of the in-cylinder combustion model of TPA is the same as that of the in-cylinder combustion model of DIWiebe; if so, enter the next step; otherwise, re-check the cylinder pressure curve of the in-cylinder combustion model of DIWiebe; Compare whether the peak value of the simulation heat release rate data of the in-cylinder combustion model of TPA is the same as that of the test heat release rate data; if so, it is determined that there is only a problem of incomplete test heat release rate data; otherwise, it is determined that there is a post-combustion phenomenon caused by abnormal fuel injection; Adjust the combustion parameters of the second in-cylinder combustion model according to the determination result.

2. The method for verifying the test data of a high-speed diesel engine based on the quasi-dimensional combustion model according to claim 1, characterized in that, The compared overall engine parameters include the exhaust temperature, and the judgment threshold of the exhaust temperature is 15°.

3. The method for checking the test data of a high-speed diesel engine based on a quasi-dimensional combustion model according to claim 1, characterized in that, The data of the heat release rate curve is obtained by calculating the measured cylinder pressure data through a heat transfer model in an experiment.

4. The method for checking the test data of a high-speed diesel engine based on a quasi-dimensional combustion model according to claim 1, wherein, The first diesel engine overall model includes models of the intake and exhaust system, fuel injection system, intercooling system, supercharging system, and cylinder system.

5. The method for checking the test data of a high-speed diesel engine based on the quasi-dimensional combustion model according to claim 1, characterized in that Adjusting the combustion parameters of the selected combustion model in step S2 includes synchronously adjusting the fuel injection timing and the combustion start timing.

6. The method for checking the test data of a high-speed diesel engine based on the quasi-dimensional combustion model according to claim 1, wherein, In step S3, the simulation data is compared with the existing experimental data. When comparing the heat release rate curves, the comparison parameters include timing, trend, and value.

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