Study on Surface Radiation Noise of a Diesel Engine Based on FEM

To evaluate the noise of a diesel engine and provide the basis for the next step for noise reduction, a boundary element model of the diesel engine has been built and finite element software is used to analyze the noise of the engine. Surface vibration velocity distribution, radiation noise spectrum, sound pressure distribution and total noise level are calculated. The calculation results obtained show that the most representative three points of the peak of SPL (sound pressure level) are 500Hz, 1200Hz and 1950Hz; total SPL is 108.99dB; the main sources of the noise of the diesel engine are oil pan, gear chamber cover and flywheel housing, these three parts should be prior; the noise of the lower part and left and right part (the gear chamber cover side and flywheel housing side) of the engine is greater than the upper part and front and rear part; improving the suspension mechanism of the internal combustion engine, optimizing the oil sump, flywheel housing and gear chamber cover and strengthening the rigidity of the skirt of the engine body can be used as the primary means of noise reduction.