低比转速离心泵的面积比原理

Area-ratio principle for centrifugal pumps with low specific-speed

依据离心泵的面积比原理,提出了建立在面积比原理基础上低比转速离心泵在加大流量设计后计算面积比、第八断面面积的方法及计算公式,此面积比和第八断面面积与泵的流量加大系数、比转速加大系数有关,解决了依据经验统计值确定面积比且不能使低比转速离心泵在设计点效率最高这一问题.实例表明:提出的计算方法能够提高低比转速离心泵的效率,充实了低比转速离心泵的设计理论.

On the basis of area-ratio principle, a calculation method and formula for area ratio and eighth volute cross-sectional area in low specific-speed pumps designed with enlarged coefficient of flow-rate were proposed, so that the relationship between several parameters such as the area ratio, eighth volute cross- sectional area, enlarged coefficient of flow-rate, specific speed, and hydraulic parameters of the impeller and volute was obtained, and the problem of inconformity of design condition with optimal one due to unreasonable empiric determination of area ratio was solved. A practical example showed that the efficiency of pumps with low specific-speed could be improved by using the calculation method presented, so that the design theory of such pumps was substantiated.