汽蚀对离心泵性能影响的实验研究

离心泵长时间运转后,会出现危害严重的汽蚀现象,造成泵性能下降,严重时影响泵的效率、寿命,甚至造成离心泵内部部件损坏。文章通过改变进口压力的方法对单泵、双泵并联、双泵串联等工况下汽蚀对离心泵性能影响进行实验研究。结果表明:当进口压力小于输送液体的饱和蒸汽压时,液体开始发生气化并伴随气泡产生,表明泵内发生汽蚀;汽蚀初期离心泵的效率开始下降,但表现不明显;随着汽蚀不断增大至严重汽蚀区时,Q 1~η曲线出现陡坡,效率出现明显下降并伴随嗡响。实验证明采用提高泵的进口压力等措施可适当减小汽蚀对泵性能的不利影响。

Experimental Study of the Influence of Cavitation on Centrifugal Pump Performance

Serious cavitation phenomenon will occur after operation of the centrifugal pump for a long time,thereby causing the performance reduction of the pump,seriously affecting the efficiency and life of the pump,and even causing damage to the internal components of the centrifugal pump.The influence of cavitation on centrifugal pump performance under single pump,double pump parallel connection and double pump series connection,etc.is studied by changing inlet pressure through experiments in the paper.The results show that when the inlet pressure is less than the saturated vapor pressure of the transported liquid,the liquid begins to gasify and bubbles are generated,thereby indicating that cavitation occurs in the pump.The efficiency of centrifugal pump begins to decline at the beginning of cavitation,but it is not obvious.Q 1~ηcurve shows steep slope with the increase of the cavitation to the serious cavitation area,thereby the efficiency is significantly declined,which is accompanied by a humming sound.It is proved that the adverse influence of cavitation on pump performance can be reduced suitably by increasing the inlet pressure and other measures.