Inducer Design to Avoid Cavitation Instabilities
Inducer Design to Avoid Cavitation Instabilities
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DOI：
10.5293/ijfms.2009.2.4.439
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发表时间：
2009-12
影响因子：
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通讯作者：
D. Kang;Toshifumi Watanabe;K. Yonezawa;H. Horiguchi;Y. Kawata;Y. Tsujimoto
中科院分区：
文献类型：
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作者：
D. Kang;Toshifumi Watanabe;K. Yonezawa;H. Horiguchi;Y. Kawata;Y. Tsujimoto
为避免空化不稳定性，设计了三种诱导器。这是通过避免顶腔与下一个叶片前缘的相互作用来实现的。第一种设计具有极大的前缘掠度，第二种和第三种分别通过减小进口叶片角度或增加设计流量来设计较小的迎角。设计流量较大的诱导轮具有较大的出口叶片角度，以获得足够的压升。由于叶尖泄漏涡腔较弱，回流涡扰动较强，具有较大扫掠的诱导器在较高流量下可抑制设计流量系数的95%以上的空化不稳定性。具有较大出口叶片角度的诱导器可以避免在较高流量下的空化不稳定性，这是由于叶尖空穴沿叶片吸力面延伸所致。进口叶片角度较小的诱导器，由于在叶片流道中首先出现空化并向上游延伸，从而避免了较高流量下的空化不稳定性。通过三维CFD计算，合理地模拟了定常空化条件下的空泡形状和吸气性能，但回流涡空泡除外。从叶片吸力侧压力分布的不同解释了不同诱导器空泡生长的差异。
Three inducers were designed to avoid cavitation instabilities. This was accomplished by avoiding the interaction of tip cavity with the leading edge of the next blade. The first one was designed with extremely larger leading edge sweep, the second and third ones were designed with smaller incidence angle by reducing the inlet blade angle or increasing the design flow rate, respectively. The inducer with larger design flow rate has larger outlet blade angle to obtain sufficient pressure rise. The inducer with larger sweep could suppress the cavitation instabilities in higher flow rates more than 95% of design flow coefficient, owing to weaker tip leakage vortex cavity with stronger disturbance by backflow vortices. The inducer with larger outlet blade angle could avoid the cavitation instabilities at higher flow rates, owing to the extension of the tip cavity along the suction surface of the blade. The inducer with smaller inlet blade angle could avoid the cavitation instabilities at higher flow rates, owing to the occurrence of the cavity first in the blade passage and its extension upstream. The cavity shape and suction performance were reasonably simulated by three dimensional CFD computations under the steady cavitating condition, except for the backflow vortex cavity. The difference in the growth of cavity for each inducer is explained from the difference of the pressure distribution on the suction side of the blades.