Influencing factors of self-priming time of multistage self-priming centrifugal pump

Abstract

Self-priming centrifugal pump are a type of drainage and irrigation equipment applied in crop irrigation, urban landscaping, 
dust prevention and cooling, and building water supply. At present, single-stage self-priming centrifugal pumps dominate the 
pump market. Hence, the market share for multistage self-priming 
pumps, which can provide high-pressure liquid, is barely adequate. 
Self-priming time is an important parameter that measures the 
self-priming performance of multistage self-priming centrifugal 
pumps. Although many studies have focused on the influences of a 
single factor on the self-priming time of single-stage self-priming 
centrifugal pumps, only a few have discussed the self-priming 
time of multistage self-priming pumps. In the current work, we 
conducted an experimental study that combined the orthogonal, 
grey relational, and self-priming time tests to investigate the influencing factors of the self-priming time of a multistage selfpriming centrifugal pump and shorten the corresponding selfpriming time. The outlet width of the impeller blade, the radial gap 
between the impeller and the diffuser, the area of backflow hole, 
and the number of stages of the multistage self-priming centrifugal pump were selected as the influencing factors in the orthogonal test. The orthogonal analysis of the self-priming time of the 
multistage self-priming centrifugal pump was conducted, and the 
results were used as the basis in obtaining the order of importance 
of all influencing factors through the grey relational test. Results 
demonstrate that self-priming time increases gradually with an 
increase in impeller blade outlet width but that it decreases continuously with an increase in stage number and area of backflow 
hole. As radial gap increases, self-priming time increases and then 
decreases. In summary, the area of backflow hole is the most important influencing factor of self-priming time of the multistage 
self-priming centrifugal pump, followed by impeller blade outlet 
width, radial gap, and stage number. These findings provide important references for shortening the self-priming time of multistage 
self-priming centrifugal pumps.