Verification method for high-speed diesel engine experimental data based on quasi-dimensional combustion model

A verification method for high-speed diesel engine experimental data based on a quasi-dimensional combustion model, comprising the steps of:

• S1, establishing a first diesel full-engine model using a GT-POWER combustion model based on existing data from diesel full-engine testing,
• S2, selecting an in-cylinder combustion model based on existing experimental cylinder pressure data and heat release rate curve data, and adjusting combustion parameters of the selected model to obtain a first in-cylinder combustion model,
• S3, comparing simulation data obtained from the first diesel full-engine model and the first in-cylinder combustion model with the existing experimental data to determine the accuracy of this first in-cylinder combustion model, establishing the in-cylinder combustion model using a direct injection Wiebe (DIWiebe) combustion model if the accuracy is unsatisfactory, and adjusting combustion parameters of the first in-cylinder combustion model using simulation data generated by this DIWiebe model to obtain a second in-cylinder combustion model,
• S4, comparing simulation data obtained from the second in-cylinder combustion model with the existing experimental data to determine the accuracy of this second in-cylinder combustion model, entering S5 if the accuracy meets requirements, establishing the in-cylinder combustion model using thermodynamic process analysis (TPA) if not, and adjusting combustion parameters of the second in-cylinder combustion model using simulation data generated by this TPA model to obtain a third in-cylinder combustion model, and
• S5, verifying the experimental data using the constructed first diesel full-engine model and the simulation data obtained from the in-cylinder combustion models;
• wherein
• S2 comprises the steps of:
• calculating an average value of the experimental heat release rate data over multiple engine cycles to obtain an averaged heat release rate;
• performing fast Fourier transform (FFT) filtering on the averaged heat release rate;
• and
• calibrating and adjusting the combustion parameters of the selected combustion model based on the filtered data, to obtain the first in-cylinder combustion model;
• S3 comprises the steps of:
• generating a cylinder pressure curve and a heat release rate curve via simulation using the first in-cylinder combustion model;
• validating the simulated cylinder pressure curve with the existing experimental cylinder pressure curve, and the simulated heat release rate curve with the existing experimental heat release rate curve, to determine whether the agreement level of the cylinder pressure curve and the heat release rate curve meets corresponding requirements;
• and entering the next step if both meet the requirements;
• and recalibrating the model's cylinder pressure curve and heat release rate curve if not;
• and
• comparing the simulated full-engine parameters with the existing experimental full-engine parameters to determine the difference between the two;
• and concluding that the accuracy of the first in-cylinder combustion model is unsatisfactory if the difference in the full-engine parameters exceeds a predefined threshold, and concluding that the accuracy is satisfactory if not;
• and
• in S4, the establishing the in-cylinder combustion model using TPA, and adjusting combustion parameters of the second in-cylinder combustion model using simulation data generated by this TPA model, comprising the steps of:
• comparing whether the simulated heat release cutoff timing from the TPA in-cylinder combustion model matches exactly that from the DIWiebe in-cylinder combustion model;
• and
• entering the next step if matched, and re-validating the cylinder pressure curve of the DIWiebe in-cylinder combustion model if mismatched;
• comparing whether a peak magnitude of the simulated heat release rate data from the TPA in-cylinder combustion model aligns with a peak magnitude of the experimental heat release rate data;
• and determining the experimental heat release rate data exhibits incomplete capture if so, and identifying abnormal fuel injection causing afterburning phenomena if not;
• and
• adjusting the combustion parameters of the second in-cylinder combustion model based on the determination results.