摘要
为分析排气系统声模态和尾口噪声的关系,采用三维有限元法对声模态和尾口声压级进行仿真计算。通过仿真分析结果和平面波理论求解结果的对比,发现了影响排气系统声模态的关键部件,改变关键部件以实现对声模态的调节;仿真分析结果表明,尾口声压级峰值频率与声模态频率相对应,调整声模态能够调节尾口声压级。应用实例中某车型由于排气系统声模态而引起尾口低频噪声大,将声模态频率从31.2 Hz移动到26.8 Hz,问题得到有效改善。
In order to analyze the relationship of exhaust system acoustic mode and tailpipe noise, acoustic mode and tailpipe sound pressure level were calculated by using 3 D finite element method. By comparing the results of acoustic mode simulation and plane wave theory calculation, the key component that influences the acoustic mode can be found and modified to adjust the acoustic mode. Peak frequency of the tailpipe SPL simulation matches the acoustic mode frequency and modification of the acoustic mode can realize the adjustment of the tailpipe sound pressure level. Due to the acoustic mode issue of exhaust system, the tailpipe low frequency noise of a certain vehicle is very large. When the acoustic mode frequency decreased from 31.2 Hz to 26.8 Hz,the problem is effectively mitigated.
引文
[1]方智,季振林.插管结构对膨胀腔消声器声学性能的影响[J].声学学报,2014,39(6):738-744.
[2]陈达亮,顾灿松,王务林,等.发动机进气消声元件设计与声学数值模拟的研究[J].汽车工程,2011,33(3):246-261.
[3]罗恩志,石岩,朱立锋,等.某SUV进气系统声模态的优化[J].汽车工程师,2017(4):26-29.
[4]耿鹏飞,石岩.汽车排气系统噪声数值仿真分析与结构优化[J].噪声与振动控制,2015,35(5):121-125.
[5]季振林.消声器声学理论与设计[M].北京:科学出版社,2015:14-15.
[6]杜功焕,朱哲民,龚秀芬.声学基础[M].3版.南京:南京大学出版社,2012:120-122.
[7]庞剑,谌刚,何华.汽车噪声与振动—理论与应用[M].北京:北京理工大学出版社,2006:214-215.
[8]詹福良,徐俊伟.Virtual.Lab Acoustic 声学仿真计算从入门到精通[M].西安:西北工业大学出版社,2013:8-9.