关键词: 罗茨式机械增压器, 振动试验, 频谱分析, 气流脉动

Abstract: In order to study the vibration characteristics of the ZNR2.4 Roots type supercharger, the prototype was subjected to vibration tests.The LMS test equipment was used to collect the vibration signals of the ZNR2.4 Roots type supercharger under different pressure ratios and different speeds.The spectrum analysis was performed on the signals with the largest mean square value under each parameter.The characteristic frequencies of airflow pulsation, reflow equalization vibration and bearings, gears, etc.were calculated.The modal analyses of the rotor were carried out.The results show that airflow pulsation and recirculation equalization vibration are as the main vibration source.When the speed is as 2 800 r/min, the meshing frequency of the gear resonates with the 38 times frequency of the shaft fundamental frequency.Finally, the method of noise reduction and vibration reduction was proposed for each vibration source, which provided reference for designing and using Roots type superchargers.

Key words: Roots type supercharger, vibration test, spectrum analysis, airflow pulsation