Development Of Torsional Vibration Program For Internal Combustion Engine Shaft System Based On Matlab

The torsional vibration of the internal combustion engine shafting is not easy to attract the attention of engineers because of its strong latency.However,the harm caused by it cannot be ignored.The vibration and noise of the internal combustion engine are increased,and the crankshaft is broken,causing serious accidents.Therefore,all countries in the world have put forward norms,must check the vibration of the shafting,and provide corresponding calculation reports.In recent years,with the rapid development of computers,the torsional vibration of the shaft system has gradually produced new methods to meet the higher requirements for vibration caused by the rapid development of internal combustion engines.In this case,it is in this case that by reading a large number of documents in recent years,the defects in the calculation of the torsional vibration of the shafting are excavated and improved,and a computer program is formed to make it more convenient to use.Firstly,by reading the previous literature,the calculation methods of moment of inertia,stiffness and damping of each component are summarized.Based on this,the Jacobian matrix method and Holtz table method are used to solve the natural frequency and mode shape of free vibration.Ensure the accuracy of the software by verifying the results of both methods.Secondly,a more comprehensive study of the gas excitation force in forced vibration is carried out.By comparing the dynamometer method and the chart method provided by the China Ship Inspection Bureau,the defects of the chart method are found and corrected,so that the calculated The harmonic coefficient is more accurate.In addition,a simplified dynamometer method is used to calculate the harmonic coefficient of the gas,and the rationality and accuracy of the simplified dynamometer are proved by comparison with the measured dynamometer.Finally,the matlab-based torsional vibration program of the internal combustion engine shafting system is programmed,which can quickly and efficiently calculate the natural frequency,formation,relative amplitude vector of each knot,resonance speed and the axis caused by the harmonics in the case of resonance in the forced vibration.Segment stress,shaft stress caused by harmonic superposition,etc.By comparing with the original calculation report,it is verified that the calculation result of the software is accurate and reasonable.This provides a powerful guarantee for the stable and reliable operation of the internal combustion engine power unit.