Unsteady Pressure Pulsation and Rotating Stall Characteristics in a Centrifugal Pump with Slope Volute
Unsteady Pressure Pulsation and Rotating Stall Characteristics in a Centrifugal Pump with Slope Volute
复制标题
斜蜗壳离心泵的非定常压力脉动和旋转失速特性
DOI：
10.1155/2014/710791
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发表时间：
2014-01-01
影响因子：
2.1
通讯作者：
Ni, Dan
中科院分区：
文献类型：
--
作者：
Zhang, Ning;Yang, Minguan;Ni, Dan
当转子的固有频率与激振频率相等时，非定常流场结构会导致离心泵产生剧烈的振动。为了减小离心泵动静干涉，提出了一种特殊的倾斜蜗壳。本文探讨了用数值模拟的方法来说明0.05ΦN-1.4ΦN工况下的非定常压力脉动和旋转失速特性。对不同流量下的压力脉动信号进行了频谱分析。研究了叶片通道内的相对速度分布，以阐明流动结构与压力谱之间的关系。在高流量下，压力谱中的主要分量总是对应于叶片通过频率（fBPF）。随着流量的减小，在0.6ΦN处，部分流从叶片吸力面分离，但分离结构对压力谱的影响不大。从0.8ΦN到0.6ΦN，压力谱的峰值仍然位于fBPF处。在旋转失速工况下，叶轮内部存在多涡结构，随着叶轮旋转而发展，表现出强烈的非定常特性。部分叶片通道堵塞严重。由于非定常的失速胞结构，在压力谱中产生失速频率，并且在不同流量下激励频率不同。
Unsteady flow structures can lead to severe vibration in centrifugal pump if the eigenfrequency of the rotor is equal to excitation frequency. In order to reduce rotor-stator interaction in centrifugal pump, a special slope volute was proposed. This paper explores the use of numerical simulation method to illustrate unsteady pressure pulsation and rotating stall characteristics under 0.05ΦN–1.4ΦN working conditions. Spectrums of pressure pulsation signals at different flow rates were analyzed. Relative velocity distributions interior blade channels were also studied to clarify correlation between flow structure and pressure spectrum. At high flow rates, predominant components in pressure spectrums always correspond to blade passing frequency (fBPF). With decreasing of flow rate, partial flow separates from suction side of blade at 0.6ΦN, but the separate structure has little impact on pressure spectrum. From 0.8ΦN to 0.6ΦN, peak values in pressure spectrums are still located at fBPF. At rotating stall working conditions, multiple vortex structures exist in impeller, which develop with rotating impeller showing intensive unsteady properties. And partial blade channels are blocked severely. Due to the unsteady stall cell structure, stall frequencies are generated in pressure spectrum, and the excitation frequencies are different at variable flow rates.