吕吉平,刘国军
摘要：利用方形微孔内声传播的等效复密度和等效复声速,推导出催化转化器载体内声传播的等效声波方程,并将催化转化器载体的等效声波方程和载体前后管道内的声波方程耦合起来,然后利用声学有限元法求解催化转化器的传递损失。通过计算分析发现,催化转化器载体提高了中高频衰减量,提高温度也能增加中高频衰减量,而孔隙率对低频和高频的作用正好相反。
关键词： 催化转化器;声学有限元;传递损失;复密度;复声速
Abstract: Acoustic wave propagation
and attenuation in catalytic converters are investigated in the present
study.First,equivalent complex density and complex sound velocity were used to
create the wave propagation equation which was solved by using acoustic
FEM.Theoretical analysis predict that monolith substrates increase the
attenuation in the high frequency area,high temperature also increases the
attenuation in the high frequency area,and porosity have opposite effect on the
low frequency and high frequency area.
Keywords: Catalytic
Converters;Acoustic FEM;Transmission Loss;Complex Density;Complex Sound
Velocity
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