Abstract:A FE-mode matching hybrid method was proposed to evaluate the transmission loss of silencers in mid-high frequency range. The acoustic variables at the inlet and outlet were expressed in terms of modal superposition form and then substituted into the FE equation of a silencer. The intrinsic functions of the system were adopted as weight functions, the sound pressures at the inlet and outlet area were integrated. Therefore, the linear equations with internal nodal acoustic variables and modal amplitude coefficients at the inlet and outlet as the unknown variables were established. The modal amplitude coefficients at the inlet and outlet were then obtained by solving the linear equations combining the corresponding boundary conditions. Furthermore, the sound powers at the inlet and outlet were gained to calculate the transmission loss of a silencer. The transmission losses of reactive and dissipative silencers were calculated, respectively to verify the effectiveness of the proposed approach in the whole frequency domain.
杨亮,季振林. 消声器中高频传递损失计算的有限元-模态匹配混合方法[J]. 振动与冲击, 2017, 36(23): 243-247.
YANG Liang JI Zhenlin. FE-mode matching hybrid approach for transmission loss prediction of silencers in mid-high frequency range. JOURNAL OF VIBRATION AND SHOCK, 2017, 36(23): 243-247.
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