Abstract:The main factors that cause pump efficiency degradation under cavitation conditions were discussed,which could be mainly associated with a decrease of the head,power and NPSHA.The change of power was discussed in detail that the calculated power could be divided into three parts with the reduction of inlet total pressure.When NPSHA becomes small,a cavity develops along the blade suction side,which reduces the suction ability near the blade leading edge but does not significantly change the pressure distribution along the pressure surface,and therefore reduces the blade loading.The cavities appear to attach to blade and induce a better blade loading at smaller NPSHA,and consequently the power of the pump increases.At severe cavitation conditions,the computed power degrades,which is contributed to the development of cavitating structures and a lower blade loading.The vapor volume distribution on the impeller indicates that the vapor first appears at the suction side of blade and then extends to the outlet of impeller with the reduction of NPSHA,the cavitation phenomenon is more severe at the suction side of blade along the hub than that near the front shroud,which may be the reason of the difference of blade loading at different locations.
李晓俊, 袁寿其, 刘威, 潘中永. 带诱导轮的离心泵空化条件下的效率下降规律[J]. 排灌机械工程学报, 2011, 29(3): 185-189.
Li Xiaojun,Yuan Shouqi,Liu Wei,Pan Zhongyong. Efficiency degrade law under cavitation conditions of centrifugal pump with inducer. Journal of Drainage and Irrigation Machinery Engin, 2011, 29(3): 185-189.
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