piston knock

英 [ˈpɪstən nɒk]

美 [ˈpɪstən nɑːk]

活塞撞击声

At the low rotate speed, the combustion noise is the primary noise, while at high rotate speed, the piston knock noise is the main noise.
明确了低转速时，燃烧噪声占主导地位；高转速时，活塞敲击噪声占主导地位。
It is proved that the improvement of piston structure is effective to decrease the impact force and the knock noise caused by the piston.
说明改进活塞的结构，对于降低活塞碰撞冲击力和活塞敲击噪声具有一定的效果。
Combustion noise and the piston knock noise are separated by adopting sound pressure method.
笔者采用声压法测量，分离出燃烧噪声和活塞敲击噪声。
It has also been clear that the source of piston knock noise is the impact between piston and cylinder sleeve by the vibration acceleration of the engine's body surface.
又通过发动机机体表面振动加速度，确定活塞敲击噪声产生的根源在于活塞与缸套的碰撞冲击。
Eventually three independent noise source signals were identified, which were combustion noise, air compressor noise and piston knock noise.
最终识别出3个主要的独立的声源信号，分别是燃烧噪声、空压机噪声和活塞敲击噪声。