High-speed diesel engine test data checking method based on quasi-dimensional combustion model

Abstract

The invention discloses a high-speed diesel engine test data checking method based on a quasi-dimensional combustion model, and belongs to the technical field of internal combustion engines. The method comprises the following steps: S1, establishing a complete machine model; s2, an in-cylinder combustion model is selected, and combustion parameters are adjusted; s3, comparing simulation data obtained by model simulation with existing test data to judge the accuracy of the model, and if the requirement is not met, establishing an in-cylinder combustion model by utilizing DIWiebe and adjusting combustion parameters of the model by utilizing the simulation data of the in-cylinder combustion model; s4, comparing simulation data obtained by simulation of the adjusted model with existing test data to judge the accuracy of the model; if the accuracy requirement is met, entering S5; otherwise, establishing an in-cylinder combustion model by using TPA and adjusting combustion parameters of the model; and S5, checking test data by using the obtained model. The accuracy of test data can be evaluated, the whole machine test process does not need to be repeated for many times, and the research and development cost of the diesel engine is greatly saved.

Description

Technical Field

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

[0002] The accuracy of diesel engine test data directly determines the accuracy of diesel engine one-dimensional simulation. If the test data error is too large, the model simulation may deviate completely from the test data. Therefore, the accuracy of test data is crucial for one-dimensional simulation. However, the test data is basically verified through multiple diesel engine tests, and there is no simulation-level method to verify the test data.

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

[0004] The present invention aims to solve one of the technical problems in the above-mentioned related art at least to a certain extent.

[0005] To this end, the purpose of the present invention is to provide a high-speed diesel engine test data verification method based on a quasi-dimensional combustion model, which can evaluate the accuracy of the test data without repeating the whole machine test process many times, thereby greatly saving the diesel engine R&D cost.

[0006] In order to solve the above-mentioned technical problems, the present invention is achieved as follows: The embodiment of the present invention provides a method for verifying high-speed diesel engine test data based on a quasi-dimensional combustion model, the method comprising: S1. Using the GT-POWER combustion model, based on the existing diesel engine test data, the first diesel engine model is established; S2. selecting an in-cylinder combustion model based on the existing test cylinder pressure data and heat release rate curve data, and adjusting the combustion parameters of the selected combustion model to obtain a first in-cylinder combustion model; S3, comparing the simulation data obtained by simulating the first diesel engine whole machine model and the first in-cylinder combustion model with the existing test data to determine the accuracy of the first in-cylinder combustion model; when the accuracy requirement is not met, establishing an in-cylinder combustion model using the DIWiebe combustion model and adjusting the combustion parameters of the first in-cylinder combustion model using the simulation data of the model to obtain a second in-cylinder combustion model; S4, comparing the simulation data obtained by simulating the second in-cylinder combustion model with the existing test data to determine the accuracy of the second in-cylinder combustion model; if the accuracy requirement is met, proceed to S5; otherwise, establishing an in-cylinder combustion model using TPA and adjusting the combustion parameters of the second in-cylinder combustion model using the simulation data of the model to obtain a third in-cylinder combustion model; S5. Using the constructed first diesel engine whole machine model and the obtained in-cylinder combustion model simulation data, and verifying the test data.

[0007] In addition, the high-speed diesel engine test data verification method based on the quasi-dimensional combustion model according to the present invention may also have the following additional technical features: In some implementations, the content of step S2 includes: The average value of the heat release rate test data of multiple cycles is solved to obtain the average heat release rate; Performing FFT filtering on the average value of the heat release rate; The combustion parameters of the selected combustion model are calibrated and adjusted based on the filtered data to obtain the first in-cylinder combustion model.

[0008] In some implementations, the content of step S3 includes: A cylinder pressure curve and a heat release rate curve are obtained by simulating the first in-cylinder combustion model; The simulated cylinder pressure curve and the existing test cylinder pressure curve, as well as the simulated heat release rate curve and the existing test heat release rate curve are checked to determine whether the respective degrees of agreement between the cylinder pressure curve and the heat release rate curve meet the requirements. If both meet the requirements, proceed to the next step. Otherwise, recheck the cylinder pressure curve and the heat release rate curve of the model. The whole machine parameters obtained by simulation are compared with the existing test whole machine parameters to determine the difference between the two; when the whole machine parameter difference is greater than a preset judgment threshold, it is determined that the accuracy of the first cylinder combustion model does not meet the requirements, otherwise it meets the requirements.

[0009] In some of the embodiments, the compared whole machine parameters include exhaust temperature, and the judgment threshold of the exhaust temperature is 15°.

[0010] In some embodiments, the data of the heat release rate curve is obtained by calculating the cylinder pressure data measured by the test through a heat transfer model.

[0011] In some embodiments, the first diesel engine complete machine model includes models of an intake and exhaust system, a fuel injection system, an intercooler system, a supercharging system, and a cylinder system.

[0012] In some embodiments, adjusting the combustion parameters of the selected combustion model in step S2 includes synchronously adjusting the injection timing and the combustion start timing.

[0013] In some of the embodiments, in step S3, the simulation data is compared with the existing test data, and when comparing the heat release rate curves, the comparison parameters include timing, trend and value.

[0014] In some embodiments, the steps of establishing the in-cylinder combustion model using TPA and adjusting the combustion parameters of the second in-cylinder combustion model using simulation data of the model in step S4 include: Compare whether the simulated heat release rate cutoff time of the in-cylinder combustion model of TPA and the in-cylinder combustion model of DIWiebe are consistent; if so, proceed to the next step, otherwise, recalibrate the cylinder pressure curve of the in-cylinder combustion model of DIWiebe; Compare the peak values ​​of the simulated heat release rate data of the TPA in-cylinder combustion model with those of the test heat release rate data to see if they are consistent; if so, it is determined that the test heat release rate only has the problem of incomplete data; otherwise, it is determined that there is afterburning caused by abnormal fuel injection; The combustion parameters of the second in-cylinder combustion model are adjusted according to the determination result.

[0015] An embodiment of the present invention also provides a high-speed diesel engine test data calibration device based on a quasi-dimensional combustion model, comprising a processor, a memory, and a software program stored on the memory. When the software program is run on the processor, the steps of the high-speed diesel engine test data calibration method based on the quasi-dimensional combustion model as described in any one of the above items can be implemented.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects: In the embodiment of the present invention, the high-speed diesel engine test data verification method based on the quasi-dimensional combustion model is provided, which can determine the accuracy of the heat transfer model for calculating the heat release rate by the test cylinder pressure during the diesel engine test phase, improve the accuracy of the simulation calculation during the diesel engine test phase, and clarify whether the current combustion state in the diesel engine cylinder meets the exhaust temperature requirement index; In the embodiment of the present invention, the high-speed diesel engine test data verification method based on the quasi-dimensional combustion model is provided, which can evaluate the accuracy of the test data without repeating the test process many times, thereby greatly saving the diesel engine R&D cost; In the embodiment of the present invention, the high-speed diesel engine test data verification method based on the quasi-dimensional combustion model is provided, which provides accurate test data to improve the accuracy of simulation, and provides an accurate in-cylinder combustion model for subsequent diesel engine performance optimization, fuel injection system optimization, supercharging system optimization and other tasks, so as to improve the performance of the diesel engine at the theoretical level; In the embodiment of the present invention, the high-speed diesel engine test data calibration method based on the quasi-dimensional combustion model is suitable for the heat transfer model parameter calibration and heat release rate data accuracy analysis during the diesel engine whole machine test, ensuring the accuracy of the in-cylinder combustion process, improving the accuracy of one-dimensional simulation, and laying the foundation for the diesel engine whole machine performance simulation.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A flow chart of a GT-POWER diesel engine model verification test data disclosed in one embodiment of the present invention; Figure 2 A flow chart of different quasi-dimensional combustion model calibration test data disclosed in one embodiment of the present invention; Figure 3 A diagram showing the verification results of cylinder pressure and heat release rate during the in-cylinder combustion process of heat release rate modeling disclosed in one embodiment of the present invention; Figure 4 A flow chart of modeling in-cylinder combustion using a DIWiebe combustion model disclosed in one embodiment of the present invention; Figure 5 A diagram showing the verification results of cylinder pressure and heat release rate during in-cylinder combustion modeling by a DIWiebe combustion model disclosed in one embodiment of the present invention; Figure 6 A flowchart of TPA modeling in-cylinder combustion disclosed in one embodiment of the present invention; Figure 7 This is a diagram showing the verification results of the cylinder pressure and heat release rate of the TPA modeling in-cylinder combustion disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The embodiments of the present invention are described in detail below through specific embodiments and application scenarios in conjunction with the accompanying drawings.

[0021] In some embodiments of the present invention, a high-speed diesel engine test data verification method based on a quasi-dimensional combustion model is provided, using one-dimensional simulation software GT-POWER, and adopting quasi-dimensional combustion to establish the in-cylinder combustion process. The accuracy of the test data is determined by verifying the cylinder pressure and heat release rate curves and comparing the simulation and test data. Based on the precise comparison results, the problems existing in the whole machine test are analyzed, and the problems existing in the diesel engine whole machine test process are clarified, providing the enterprise with a subsequent test optimization direction, saving diesel engine R&D costs, and improving test efficiency.

[0022] In some embodiments of the present invention, based on the GT-POWER diesel engine model verification process, please refer to Figure 1 As shown, the GT-POWER combustion model is used to establish diesel engine subsystem models such as the diesel engine intake and exhaust system, fuel injection system, intercooling system, supercharging system, and cylinder system based on a diesel engine test data. The key parameters of the subsystem models are calibrated with reference to a diesel engine test data. After the calibration of the above parameters is completed, the in-cylinder combustion model is selected based on the test cylinder pressure and heat release rate curve. 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: the in-cylinder combustion model is calibrated with the test heat release rate curve, and the in-cylinder combustion model is calibrated with the test cylinder pressure data; after the calibration is completed, the cylinder pressure and heat release rate curves of the simulation and the test are checked. After the cylinder pressure and heat release rate curves are checked, if the remaining parameters have deviations within the allowable error range, it is proved that the model simulation can simulate the in-cylinder combustion process of the diesel 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, there is no need to set other parameters of the combustion model; proofreading and checking refer to comparing the simulation data with the test data to determine the degree of similarity. Based on the above modeling and calibration process, the present invention discusses a method for verifying high-speed diesel engine test data based on a quasi-dimensional combustion model. When the cylinder pressure and heat release rate curves meet the requirements but the other parameters exceed the allowable error range, it is necessary to adjust the parameters of the in-cylinder combustion model. The parameters of the in-cylinder combustion model can be adjusted based on the DIWiebe combustion model and the TPA combustion model in turn.

[0023] For calibration test data of different quasi-dimensional combustion models, please refer to Figure 2As shown, firstly, the heat release rate test data of multiple cycles are averaged, and the heat release rate average value is Fourier filtered (FFT filtered) to obtain smooth heat release rate curve data for calibrating the in-cylinder combustion model. After the in-cylinder combustion model is calibrated with the test heat release rate data, the injector setting parameters will no longer affect the simulation results. Only the injection timing and combustion start time parameters will affect the simulation results. Therefore, the injection timing and combustion start time parameters are adjusted again. After the adjustment is completed, the simulation and test cylinder pressure curves are simulated and checked, and the degree of coincidence of the heat release rate curves of the simulation and the test is compared. The heat release rate curve is calculated by the heat transfer model from the cylinder pressure measured in the test. In theory, the cylinder pressure and heat release curves calculated by the heat release rate curve calibration cylinder combustion model simulation should completely overlap with the cylinder pressure and heat release rate curves obtained in the test. When comparing the heat release curve, the timing, trend and important values ​​can be emphasized. When the comparison of the cylinder pressure curve and the heat release rate curve meets the requirements, it means that the above model meets the requirements and can be used to check the subsequent test data. After comparing the cylinder pressure and heat release rate curves, compare the whole machine parameters, such as exhaust temperature, boost pressure, intake air flow, etc. The simulation results of the whole machine parameters should be basically consistent with the test results in theory. However, from the simulation results, after the cylinder pressure curve is checked, the simulated heat release rate curve is significantly higher than the test heat release rate curve. Please refer to Figure 3 As shown in the figure, the exhaust temperature is much lower than the test data. Specifically, the simulated exhaust temperature before the turbine is much lower than the test exhaust temperature. This result proves that there is a large error in the test heat release rate data and it needs to be checked and verified.

[0024] In some embodiments of the present invention, see Figure 4 As shown in the figure, the process of modeling in-cylinder combustion using the DIWiebe combustion model includes: firstly, using the DIWiebe combustion model to establish the in-cylinder combustion process, and using its simulated heat release rate data to replace the experimental heat release rate data to calibrate the in-cylinder combustion, so as to adjust the combustion model parameters. Then, calibrate the cylinder pressure curves under simulation and test, and then compare the end time and peak data of the heat release rate curves under simulation and test, and finally compare the exhaust temperature data under simulation and test.

[0025] In this example, see Figure 5As shown, the cylinder pressure curve of the DIWiebe combustion model is consistent, the simulated heat release rate curve is basically consistent with 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 ends naturally at 140deg, and the experimental heat release rate curve ends at 90deg. The DIWiebe combustion model proves that the experimental heat release rate data is missing. At the 90deg position of the experimental heat release rate curve, the heat release rate does not drop to 0 naturally, but it stops and returns to 0. This is most likely due to the fact that 90deg is set as the cutoff time when the test cylinder pressure is used to measure the heat release rate. Therefore, the experimental heat release rate data is used to calibrate the in-cylinder combustion process, which 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.

[0026] The test results are as follows: When the other parameters of the DIWiebe combustion model are basically consistent with the test data, the simulated vortex front exhaust temperature is 48°C lower than the test vortex front exhaust temperature, and there is a non-negligible deviation. This shows that the heat release rate curve calculated by the DIWiebe combustion model can only prove that the test heat release rate curve is truncated in advance, and cannot prove when the actual heat release rate curve is truncated. And under the premise that the cylinder pressure curve verification is almost completely consistent, the simulated heat release rate curve is significantly wider than the test heat release rate, but the simulated vortex front exhaust temperature is significantly lower than the test exhaust temperature, which is contrary to the theory. That means the time for the test heat release rate to return to 0 is higher than 140deg or the heat release rate obtained by the test calculation is much lower than the actual in-cylinder combustion. This is because the heat release rate curve is directly measured by the cylinder pressure measured curve. After other systems are verified, the above contradictions appear. It is speculated that abnormal fuel injection leads to obvious afterburning in the cylinder and even exhaust port combustion. Therefore, in the test, the combustion analyzer can only collect the heat released by the combustion of the fuel in the cylinder, but cannot collect the heat released by the combustion of the fuel entering the exhaust duct. Therefore, it is necessary to replace the combustion model and recalculate the heat release rate.

[0027] In some embodiments of the present invention, the test cylinder pressure data is used to model the in-cylinder combustion, which is also called TPA-calibrated in-cylinder combustion. The heat release rate curve is obtained according to the cylinder pressure curve and based on the law of conservation of energy. If exhaust port combustion occurs, the combustion heat release rate curve will be significantly lower. The test cylinder pressure curve can most directly display the in-cylinder combustion process, so the present invention attempts to directly use the test cylinder data (TPA) to model the in-cylinder combustion process. In the method of modeling the in-cylinder combustion model based on the test cylinder pressure data, the cylinder pressure curve is directly measured by the test, and the heat release rate curve is obtained by analyzing the in-cylinder heat transfer model. Therefore, the cylinder pressure curve is the test parameter that is closest to the real process of the diesel engine. The test cylinder pressure curves of multiple cycles are averaged, and FFT smoothing filtering is performed based on the cylinder pressure average value to obtain the cylinder pressure curve of the modeled combustion process.

[0028] In this example, see Figure 6 As shown in the figure, the process of TPA modeling in-cylinder combustion includes: first averaging multiple cycle cylinder pressure test data; performing FFT filtering on the cylinder pressure average value; calibrating the in-cylinder combustion model (TPA) with the filtered cylinder pressure data; then adjusting the injection timing; calibrating the simulation and test cylinder pressure curves to ensure that the start time of the simulation combustion is consistent with the test; then comparing the heat release rate curve obtained by TPA simulation with the test heat release rate curve to see if they are consistent. If they are consistent, check the calibration of the whole machine parameters; if they are inconsistent, it is necessary to adjust the cylinder heat transfer model parameters, mainly the piston convection heat transfer coefficient and the cylinder convection heat transfer coefficient. Coefficient, valve convection heat transfer coefficient, at this time compare the whole machine characteristic parameters: power, torque, fuel consumption rate, explosion pressure, temperature before intercooler, pressure after intercooler, exhaust temperature before and after turbine and other parameters; if the whole machine parameters are calibrated correctly and the simulated cylinder pressure curve and heat release rate curve are 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 calibrated correctly, the simulated heat release rate curve is significantly higher than the test heat release rate curve, and the whole machine parameters except the simulated turbine exhaust temperature is significantly lower than the test exhaust temperature, it means that extreme afterburning phenomenon occurs, mainly due to exhaust duct combustion.

[0029] See also Figure 7 As shown, the cylinder pressure simulation results of the TPA modeled in-cylinder combustion model are completely consistent with the test results. The peak heat release rate is significantly higher than the test heat release rate peak, and the same heat release ends at 140 degrees as the DIWiebe combustion model modeled combustion. This confirms that the extreme combustion caused by abnormal fuel injection occurred during the test - exhaust port combustion. The default setting of the circulating oil volume in the GT-POWER software simulation is in the ideal situation of in-cylinder combustion. TPA is calibrated as the most accurate display of the test combustion process. After the whole machine parameters are verified, the test heat release rate curve is still low and the simulated exhaust temperature is obviously low, which proves the occurrence of extreme exhaust port combustion. At the same time, since the TPA modeled in-cylinder combustion is theoretically the most accurate in-cylinder combustion modeling method, and the heat release rate curve obtained by the TPA method obviously has the phenomenon of late heat release, it can be confirmed that the test heat release rate curve is truncated in advance.

[0030] 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 curve is accurate.

[0031] (1) Modeling in-cylinder combustion with experimental heat release rate data. If the simulation of various parameters of the diesel engine is basically consistent with the test after the cylinder pressure curve is accurately calibrated, it can be considered that the cylinder pressure and heat release rate curve obtained from the test is accurate. If the simulation results of parameters such as exhaust temperature and the test results show a large deviation after the cylinder pressure curve is accurately calibrated, it means that there is a large error in the experimental heat release rate curve, and the deviation is mainly concentrated in the heat transfer parameters of the heat release rate model and the cutoff time of the heat release rate.

[0032] (2) The DIWiebe combustion model models in-cylinder combustion. Adjust the DIWiebe combustion parameters and calibrate the cylinder pressure curve. After the cylinder pressure curve is calibrated, compare the simulation and experimental heat release rate curves. Analyze the cutoff position of the heat release rate curve. If the crankshaft angles corresponding to the simulation and experimental heat release rate cutoffs are basically the same, it means that the experimental heat release rate cutoff time is correct; if there is a large deviation, it means that the cutoff time is incorrect and it is necessary to use TPA cylinder pressure calibration to continue calculation. After the heat release rate cutoff time is calibrated, compare other parameters such as simulation and experimental exhaust temperature. 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 means that serious afterburning occurs.

[0033] (3) Modeling in-cylinder combustion using test cylinder pressure data (TPA). The test cylinder pressure data is the data closest to the in-cylinder combustion during the diesel engine test. Therefore, the heat release rate obtained by TPA calibration of the in-cylinder combustion process is the most accurate heat release rate data. At this time, the simulation and test heat release rate data are compared. If the heat release rate cutoff position is consistent with the heat release rate cutoff position calculated by the DIWiebe combustion model, it proves that the heat release rate curve cutoff position calculated by the DIWiebe combustion model is accurate. At this time, the heat release rate value calculated by TPA is compared with the test heat release rate value and the whole machine parameters. If they are basically consistent, it can be considered that the test data is correct; if there is a large deviation between the heat release rate value calculated by TPA and the test heat release rate value, then the test combustion process is obviously abnormal, and the actual heat release rate should be based on the heat release rate calculated by TPA calibration.

[0034] The parts of the present invention that are not described in detail may refer to the prior art in the art or are technologies known to those skilled in the art.

[0035] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A high-speed diesel engine test data verification method based on a quasi-dimensional combustion model, characterized in that: The method comprises: S1. Using the GT-POWER combustion model, based on the existing diesel engine test data, the first diesel engine model is established; S2. selecting an in-cylinder combustion model based on the existing test cylinder pressure data and heat release rate curve data, and adjusting the combustion parameters of the selected combustion model to obtain a first in-cylinder combustion model; S3, comparing the simulation data obtained by simulating the first diesel engine whole machine model and the first in-cylinder combustion model with the existing test data to determine the accuracy of the first in-cylinder combustion model; when the accuracy requirement is not met, establishing an in-cylinder combustion model using the DIWiebe combustion model and adjusting the combustion parameters of the first in-cylinder combustion model using the simulation data of the model to obtain a second in-cylinder combustion model; S4, comparing the simulation data obtained by simulating the second in-cylinder combustion model with the existing test data to determine the accuracy of the second in-cylinder combustion model; if the accuracy requirement is met, proceed to S5; otherwise, establishing an in-cylinder combustion model using TPA and adjusting the combustion parameters of the second in-cylinder combustion model using the simulation data of the model to obtain a third in-cylinder combustion model; S5. Using the constructed first diesel engine whole machine model and the obtained in-cylinder combustion model simulation data, and verifying the test data.

2. The high-speed diesel engine test data verification method based on the quasi-dimensional combustion model according to claim 1 is characterized in that: The content of step S2 includes: The average value of the heat release rate test data of multiple cycles is solved to obtain the average heat release rate; Performing FFT filtering on the average value of the heat release rate; The combustion parameters of the selected combustion model are calibrated and adjusted based on the filtered data to obtain the first in-cylinder combustion model.

3. The high-speed diesel engine test data verification method based on the quasi-dimensional combustion model according to claim 1 is characterized in that: The content of step S3 includes: A cylinder pressure curve and a heat release rate curve are obtained by simulating the first in-cylinder combustion model; The simulated cylinder pressure curve and the existing test cylinder pressure curve, as well as the simulated heat release rate curve and the existing test heat release rate curve are checked to determine whether the respective degrees of agreement between the cylinder pressure curve and the heat release rate curve meet the requirements. If both meet the requirements, proceed to the next step. Otherwise, recheck the cylinder pressure curve and the heat release rate curve of the model. The whole machine parameters obtained by simulation are compared with the existing test whole machine parameters to determine the difference between the two; when the whole machine parameter difference is greater than a preset judgment threshold, it is determined that the accuracy of the first cylinder combustion model does not meet the requirements, otherwise it meets the requirements.

4. The high-speed diesel engine test data verification method based on the quasi-dimensional combustion model according to claim 3 is characterized in that: The compared whole machine parameters include exhaust temperature, and the judgment threshold of the exhaust temperature is 15°.

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

6. The high-speed diesel engine test data verification method based on the quasi-dimensional combustion model according to claim 1 is characterized in that: The first diesel engine complete machine model includes models of an intake and exhaust system, a fuel injection system, an intercooler system, a supercharging system and a cylinder system.

7. The high-speed diesel engine test data verification method based on the quasi-dimensional combustion model according to claim 1 is characterized in that: The adjustment of the combustion parameters of the selected combustion model in step S2 includes synchronously adjusting the injection timing and the combustion start timing.

8. The high-speed diesel engine test data verification method based on the quasi-dimensional combustion model according to claim 1 is characterized in that: In step S3, the simulation data is compared with the existing test data. When comparing the heat release rate curves, the comparison parameters include timing, trend and value.

9. The high-speed diesel engine test data verification method based on the quasi-dimensional combustion model according to claim 1 is characterized in that: The contents of establishing the in-cylinder combustion model by using TPA and adjusting the combustion parameters of the second in-cylinder combustion model by using the simulation data of the model in step S4 include: Compare whether the simulated heat release rate cutoff time of the in-cylinder combustion model of TPA and the in-cylinder combustion model of DIWiebe are consistent; if so, proceed to the next step, otherwise, recalibrate the cylinder pressure curve of the in-cylinder combustion model of DIWiebe; Compare the peak values ​​of the simulated heat release rate data of the TPA in-cylinder combustion model with those of the test heat release rate data to see if they are consistent; if so, it is determined that the test heat release rate only has the problem of incomplete data; otherwise, it is determined that there is afterburning caused by abnormal fuel injection; The combustion parameters of the second in-cylinder combustion model are adjusted according to the determination result.

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