口环间隙变化对高转速离心泵性能的影响  

Effects of wear-ring clearance on performance of high-speed centrifugal pump

作　　者：杨从新[1] 强盼 安莎[2] 徐楠[2] 刘军年[2] 

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050 [2]西安航天动力研究所,陕西西安710100

出　　处：《排灌机械工程学报》2017年第1期18-24,共7页Journal of Drainage and Irrigation Machinery Engineering

摘　　要：为了阐明口环间隙变化对高转速离心泵性能的影响,以一台转速n为38 500 r/min的离心泵为研究对象,基于泵几何参数,建立前、后口环间隙变化为0.01 mm的16种匹配方案,通过数值模拟方法预测了不同匹配方案下离心泵的性能.结果表明:当后口环间隙越小时,效率及轴功率对前口环间隙变化的敏感度越高;当前口环间隙越小时,效率及轴功率对后口环间隙变化的敏感度也越高;当前口环间隙一定时,随着后口环间隙的增大,扬程下降;当后口环间隙一定时,扬程随着前口环间隙的增大出现微小上升;无论是小间隙匹配还是大间隙匹配,前、后口环处泄漏量均随着流量的增大而减小;匹配的间隙值越大,对应模型的扬程及效率越低,功率越大,扬程随流量的变化越明显;口环内部水力阻力的形成主要是消耗了静压,液体通过口环后,其速度的变化并不明显;随着口环间隙的增大,在口环内同一位置处静压下降,动压上升.In order to clarify effects of wear-ring clearance on the performance of high-speed centrifugal pump, a centrifugal pump with speed of 38 500 r/min is studied. Firstly, 16 cases are generated by combining the clearances of the front and rear wear-rings with 0.01 mm increment, then the performance of the pumps with these wear-ring clearance are predicted by means of numerical simulation. The results show that when the rear wear-ring clearance are smaller, the efficiency and shaft power are more sensitive to the change in the front wear-ring clearance. Likewise, when the front wear-ring clearance is kept smaller, the efficiency and shaft power are sensitive to the change in the rear wear-ring clearance too. The head of pump decreases with increasing rear wear-ring clearance at a constant front wear-ring clearance. However, the head rises slightly with increasing front wear-ring clearance at a constant rear wear-ring clearance. Even though the leakage through the front and rear wear-ring gaps decreases with increasing flow rate whatever both the clearances are, the efficiency and head are lower, and the head varies more significantly against flow rate with two increasing clearances. The hydraulic resistance in a wear-ring gap is mainly to generate a liquid static pressure drop because the velocity of liquid does not change obviously at the wear-ring outlet. With the increase of wear-ring clearance, the static pressure drop and dynamic pressure at an axial position rise in the wear-ring clearance.

关 键 词：离心泵 高转速 口环间隙 匹配 性能 

分 类 号：S277.9[农业科学—农业水土工程] TH311[农业科学—农业工程]