动噪声 meaning in English

motive noise

This paper aimed at the low noise aerodynamic performance of automobile cooling fan , set out from the fluid dynamics and the mechanism of noise generation and radiation , mathematical model has been erected to analyze the influence of the main structural parameters on noise performance
本文着眼于汽车冷却风扇的低噪声气动性能，从汽车冷却风扇的流体动力学理论和气动噪声的产生机理出发，建立数学模型，分析风扇主要结构参数对冷却风扇噪声性能的影响。