Yue Dongpeng  

(School of Mechanical Engineering, Tianjin University, Tianjin 300072)

Hao Zhiyong

(College of Mechanical and Energy Engineering, Zhejiang University,  Hangzhou 310027)

Liu Yuehui  Han Jun

(School of Mechamical Engineering, Tianjin University, Tianjin 300072)

Abstract: The acoustic powers of noises radiated by various components are estimated with a function of square of vibration velocity to time and their averages at vibration surfaces of engine components that radiate noises. The main sources of surface noises of a four-cylinder diesel engine used in a vehicle are identified. Then the main sources of surface noises are found out by sound intensity testing technique, too. The study results of surface vibration testing are verified by sound intensity testing with good agreement. Improvement direction of diesel noise control is put forward based on the previous study.

Key words: Diesel  Source of noise  Surface vibration  Sound intensity method

CLC No: TH132.4U464

国家自然科学基金资助项目(No.50175078). Received 20030731, received in revised form 20031225