Characteristics of pressure pulsation in multi-stage submersible pump
Shi Weidong1, Xu Yan1, Zhang Qihua1, Wang Guotao2, Lu Weigang1, Ma Dongqi3
1.National Research Center of Pumps, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.Jiangsu Province Special Equipment Safety Supervision Inspection Institute Changzhou Branch, Changzhou, Jiangsu 213016, China; 3.Fujian Academy of Mechanical Sciences, Fuzhou, Fujian 350005, China
Abstract:In order to investigate the transient operation characteristics of multi-stage submersible pumps, three-dimensional, unsteady numerical simulations were conducted by using the standard k-ε turbulence model, SIMPLEC algorithm based on the sliding mesh technique in Fluent. The perfor-mance of the pump was obtained and compared with the experimental results. Besides, the pressure pulsations at various monitoring points were acquired; subsequently they were analyzed in time and frequency domains, respectively. It was demonstrated that the pressure fluctuation at all the monitoring points changes periodically with time, its number of periods is identical to the number of blades but less affected by the number of guide vane blades, its frequency is close to the blade passing frequency. The frequency of pressure fluctuation within the impeller increases gradually towards the impeller outlet and approaches the maximum value there, while the variation tendency of the frequency is opposite within the guide vane. The mostly dramatic pressure fluctuation occurs at the impeller outlet, the main frequency at various monitoring points is almost equal to the blade passing frequency. The amplitude of pressure pulsation coefficient at the monitoring points in the second stage impeller is higher than the first stage impeller. There still are two peaks in the pressure pulsation profiles in the second stage guide vane, suggesting pressure pulsation is not eliminated completely there. Additionally, the main frequency of pressure pulsation in the first stage guide vane is different from the second stage guide vane.
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