【摘要】 分析不同转速下直接空冷风机桥架振动实测速度响应表明,传统简谐扰力作用的振动响应不能反映实测振幅、相位缓慢变化的窄带随机特性;采用载波理论建立的风机扰力模型可有效反映桥架振动的随机性。结合风机桥架振动时、频域分析结果,以速度响应功率谱为目标识别扰力模型参数。模拟结果表明,扰力模型标准差随风机转速增加而增大。更多还原

【Abstract】 The vibration response to traditional harmonic exciting force can’t be used to the narrowband random characteristics of the measured vibration velocities of direct air cooling fan bridges. Consequently,a random exciting force model based on the carrier wave theory was proposed to reflect effectively the random features of the bridge’s vibration.Combined with the analysis results time domain and frequency one,the exciting force model’s parameters were identified with the power spectra of the velocity responses the targets. The results showed that the standard deviation of the random exciting force model increases with increase in rotating speed of fans.更多还原