基于快速多极边界元的吸声材料声屏障降噪效果分析

Analyses on the Noise Reduction Effect of Sound Barrier with Absorbing Material Based on FMBEM

针对传统快速算法在高频处效率低和对角式快速算法在低频处不稳定这一问题,推导出带有吸声材料的快速多极计算表达式.在此基础上,以无限长圆柱为算例对所推导的快速多极计算表达式进行了精度验证,结果显示:快速多极算法保持了传统边界元算法的高精度的优点,并可有效地提高计算效率.对不同顶端结构带吸声材料的声屏障声场进行了分析,结果表明:合理的顶端结构能够有效提高屏障的降噪效果,同时黏附吸声性材料也有利于提高降噪效果.

The traditional fast algorithm is inefficient at high frequency,and diagonal fast algorithm is not stable at low frequency.In order to solve the problem,the fast multipole expression for the simulation of the noise reduction effect of absorbing sound barrier was derived based on Fast Multipole Boundary Element Method(FMBEM).On this basis,a numerical example of an infinite cylinder was carried out to verify the accuracy of the algorithm,and the results show that the fast multipole algorithm has the same accuracy with the traditional fast algorithm,and can improve the computational efficiency.The sound field of different top structures with sound absorbing materials was analyzed,and the results show that the reasonable top structure can increase the noise reduction effect of the barrier effectively,and the sound absorbing materials are also beneficial to improve the effect of noise reduction.