A specialized noise test bench of automobile cooling fan was designed to carry out the bench test and the outer vehicle acceleration noise test also was conducted 設計制造了發動機冷卻風扇噪聲性能測試專用試驗臺,用于冷卻風扇的臺架試驗。同時,使用新的風扇原型進行了整車車外加速噪聲性能測試。
In order to carry out the acoustic and aerodynamics performances tests , seven resonators are designed and made , and a specialized engine intake silencer and exhaust silencers test bench was designed . the tests and analysis are performed as well . on the basis of the intake noise spectrum of sc7080a , a three - parallel - connected resonant silencer is designed , and that has efficiently controlled the acceleration noise of sc7080a 在此基礎上設計并加工了兩類七個共振型進氣消聲器,研制了發動機進排氣消聲器性能測試實驗臺,開發了發動機進排氣消聲器聲學性能測試軟件,并在該實驗臺上測試了所設計的進氣消聲器靜態工況下的傳聲損失,從實驗的角度研究了共振腔的尺寸、形狀對其共振頻率的影響及其趨勢。
The bench test indicated that noise of the designed cooling fan was apparently decreased . at the important revolution , 3 ~ 4 . 5db ( a ) noise decrease can be expected in the bench test and 1 . 5 ~ 2db ( a ) decrease in the acceleration noise test . with the modification of shroud , a better result can be expected 風扇臺架試驗測試結果表明,針對研究車型( sc6331b )改進設計的冷卻風扇,噪聲得到較大幅度的下降,在發動機主要工作轉速下,風扇噪聲下降3 ~ 4 . 5db ( a ) ,由此帶來了1 . 5 ~ 2db ( a )左右的整車車外加速噪聲的下降。