摘要
为了研究射流式自吸喷灌泵射流喷嘴的内特性,利用流体力学基本原理,对射流喷嘴阻力系数、流量系数进行了理论推导.设计了4种不同尺寸的射流喷嘴,对4种喷嘴的阻力系数、流量系数进行了理论计算,得到了不同出口直径下各系数的变化规律.对分别安装4种射流喷嘴的喷灌泵进行了自吸性能的试验.结合试验结果和各系数的变化规律,分析了射流喷嘴阻力系数和流量系数对射流式自吸喷灌泵自吸性能的影响.结果表明,随着喷嘴出口直径的增大,阻力系数减小,流量系数增大,自吸时间缩短,但达到一定程度后,卷吸作用减弱,自吸性能变差.
In order to study the characters of self-priming irrigation pumps＇ jet nozzles, fluid mechanics principles were used to derive the resistance coefficients and flow coefficients of self-priming irrigation pump. Four different jet nozzles were designed. By calculating the resistance coefficients and flow coefficients, change laws of coefficients with different outlet diameters were obtained. Four self-priming irrigation pumps with four jet nozzles were tested by the test-bed. Combined with the results of experiments and change laws of coefficients, the influences of resistance coefficients and flow coefficients on self-priming capability were studied. The results show that resistance coefficients decrease and flow coefficient increase with the increasing jet nozzle outlet diameters. At the same time, self-priming time was shortened. But the self-priming capability deteriorates with the weakening of jet entrainment effect in certain extent.
出处
《排灌机械》
EI
2009年第4期228-231,共4页
Drainage and Irrigation Machinery
基金
国家863计划项目(2006AA100211)
关键词
射流式自吸喷灌泵
射流喷嘴
阻力系数
流量系数
射流卷吸
自吸时间
self-priming irrigation pump
jet nozzles
resistance coefficients
flow coefficients
jet entrainment
self-priming time
