Muffler Performance Prediction Using the Boundary Element Method

以邊界元素法預估消音器之性能

曾智義(C. I. Tseng) ； 吳鼎文(T. W. Wu) ； 陳建志(J. C. Chen) ； 羅浩(H. Luo) ； 黃河潤(H. J. Huang)

《中華民國振動與噪音工程學會論文集》 1996 (1996/04) Pp. 83-92

https://doi.org/10.30028/CSSVANNUAL.199604.0083

摘要

不同於一般研究之簡單消音器，眞正應用的消音器其內部有複雜的幾何形狀，像延伸管、隔板、穿孔管等，這類問題若以三維實體有限元素來分析將十分困難。本文則是以SYSNOISE邊界元素法軟體來探討消音器之效率與性能，電腦模擬結果並與自行發展之混體邊界元素法程式及實驗做比較驗証。本研究並以三點法來評估消音器之傳遞損失，其優點為只要執行一次程式即可獲得可靠答案，而傳統四埠法則需執行兩次。最後並探討四種不同消音器性能，且與理論、數值方法、實驗測試等交互做比對，以驗証模擬與分析方法之可靠度。

並列摘要

Real-world mufflers usually contain complex internal geometry, such as extended inlet/outlet tubes, thin baffles, and perforated tubes. Some of the problems can be solved by commercial acoustic BEM (boundary element method) codes. In this paper, we present some initial results of using the indirect BEM in SYSNOISE. The results are compared to available experimental data as well as results from a direct mixed-body BEM code. The transmission loss (TL) is evaluated by the three-point method, instead of the conventional four-pole theory. The three-point method requires only one single BEM run to get the TL value at each frequency. Four different test cases of increasing modeling difficulty are evaluated, with the last one being very close to a real-world motorcycle muffler.