Abstract：Based on the analysis of pressure fluctuations at different flow regions in centrifugal pumps, measuring point arrangements on suction chamber, volute casing and delivery pipes are proposed. Especially, the distribution scheme of measuring points near volute tongue area was discussed in details. The impacts of sampling frequency and sampling time on the experimental results were analysed. The results show that the sampling frequency determines the range of frequency domain, and sampling time determines the frequency resolution. Combining the sampling theory with features of the FFT method, two constraint equations for determining sampling frequency and sampling time are established. Five window functions used for FFT analysis were compared by means of their frequency resolutions and amplitudes. The rectangular window function is recommended because of its advantage in the capturing the main frequency and keeping its amplitude lossless for centrifugal pumps.
姚志峰， 王福军， 肖若富， 严海军， 刘竹青， 王敏. 离心泵压力脉动测试关键问题分析[J]. 排灌机械工程学报, 2010, 28(3): 219-223.
Yao Zhifeng, Wang Fujun, Xiao Ruofu, Yan Haijun, Liu Zhuqing, Wang Min. Key issues in pressure fluctuation experimentsfor centrifugal pumps. Journal of Drainage and Irrigation Machinery Engin, 2010, 28(3): 219-223.
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