发电机组排气消声器仿真分析与改进设计

Simulation Analysis and Improvement Design of Diesel Generator Exhaust Mufflers

使用三维数值计算方法对某柴油发电机组排气消声器进行声传递损失和流动阻力损失的预测,针对其低 频消声量不足和阻力损失偏大的问题进行改进设计。通过改进膨胀腔和插入管结构,并在入口段增加吸声材料,进行 仿真对比分析,结果表明:改进后的消声器在全频段噪声均有不同程度改善,且阻力损失也得到明显降低。配机验证 结果表明:消声器改进后,排气噪声总声级降低了5.8dB,冷却水温降低了3°C,与仿真趋势吻合良好。

Three-dimensional numerical methods are used to predict the acoustic transmission loss and flow resistance loss of the diesel generator exhaust muffler.Due to the deficient sound elimination at low frequencies and overlarge resistance loss of the muffler,an improvement design of the muffler is conducted.The structures of the dilatation cavity and the insertion tube are improved and the sound absorption material is attached to the inlet section.The simulation results show that the improved muffler’s performance is improved in full frequency range,and the flow resistance loss is obviously decreased.The matching experiments show that the total sound pressure level of the exhaust muffler is decreased by 5.8 dB,and the cooling water temperature is reduced by 3°C.The measurement results agree well with the simulation trend.