Research on the Impact Force Induced by Piston Slap and Vibration of Internal Combustion Engine Block
|Course||Power Machinery and Engineering|
|Keywords||Diesel engine Organism Vibration Piston percussion Statistical Energy Analysis|
Piston percussion force is the the diesel mechanical vibration noise excitation source, the cylinder wall occurred inside the cylinder, makes it difficult to accurately measure the piston knocking force, therefore, in theory to establish a suitable model to calculate the piston percussion piston percussion become an effective method to obtain the tap information. With increasingly stringent internal combustion engine vibration and noise regulations, the internal combustion engine vibration and noise prediction technology, but there is no good solution to the high frequency vibration and noise prediction, statistical energy analysis as a predictor of high frequency vibration and noise powerful tool more widely used, but in some areas of engineering, but you can not find many of the internal combustion engine's noise and vibration analysis. Therefore, the paper attempts to use statistical energy analysis methods to the study of the body surface vibration caused by the diesel engine piston percussion. In this paper, the test methods to get a the percussion point at the points mobility characteristics, combined with theoretical analysis of the piston and cylinder liner the percussion point at the equivalent mass, equivalent stiffness and equivalent damping piston percussion process model considering the gas pressure in cylinder piston, connecting rod force, friction piston and the cylinder liner, the striking force of the piston and the piston secondary motion calculated and analyzed using MATLAB language, obtained with the actual operating condition of the internal combustion engine is closer the striking force. ZH1110 diesel engine piston percussion caused by the body surface vibration, established Liner - a body of statistical energy analysis subsystem model combination method to get through the trials and statistical energy analysis, including modal density equivalent quality, internal loss factor, coupling loss factor, including all parameters, the use of these parameters caused by percussion piston diesel engine body surface vibration prediction, the vibration velocity curve. Paper also the effectiveness of the band of the individual parameters are analyzed to determine a suitable frequency range of statistical energy analysis, and was verified by experiment. ZH1110 diesel engine block the surface vibration test research, test results and statistical energy analysis and forecasting results were compared by a coherent analysis of technical indirect qualitative verify this piston the percussion cylinder liner model reasonable; time domain, frequency domain analysis results prove the reasonableness established statistical energy analysis model predicted vibration response within a certain frequency range.