Characters of head of low head pump station and the pump shaft power areanalyzed. Influence of each single factor on pump shaft power is expressed as change of specificshaft power. (non-dimensional) and the probabilit...Characters of head of low head pump station and the pump shaft power areanalyzed. Influence of each single factor on pump shaft power is expressed as change of specificshaft power. (non-dimensional) and the probability density function is determined. Influences ofmultiple factors on pump shaft power are analyzed. Method of calculating none over-loadedprobability of motor by integration by successive reductions is put forward and then relationbetween power spare coefficient and none over-loaded reliability of electric motor is established.Influences of all factors on pump shaft power being considered completely; power spare coefficientsof motor are calculated in three kinds of heads (changing and unchanging), two kinds of dirty-outconditions. Electrical motor power spare coefficients should be chosen as 1.20 approx 1.44, 1.11approx 1.19, 1.09 approx.14 respectively when pump heads are 4, 7, 9.5 m. The results mean much toreasonable choose of electrical motors in large pump stations, increasing reliability of pump unitsand saving equipment investment.展开更多
By means of the analysis of the internal flow within inlet passage of large pumping sta-tion, an analysis of 3-D direct boundary element for the flow has been presented on the potentialflow assumption, and a calculati...By means of the analysis of the internal flow within inlet passage of large pumping sta-tion, an analysis of 3-D direct boundary element for the flow has been presented on the potentialflow assumption, and a calculation and an experimental proof for the inlet passage of 30 angle-type axial pumping station have been made. Based on the analysis of the calculations and theexperiments, the calculation method is feasible and believable.展开更多
文摘Characters of head of low head pump station and the pump shaft power areanalyzed. Influence of each single factor on pump shaft power is expressed as change of specificshaft power. (non-dimensional) and the probability density function is determined. Influences ofmultiple factors on pump shaft power are analyzed. Method of calculating none over-loadedprobability of motor by integration by successive reductions is put forward and then relationbetween power spare coefficient and none over-loaded reliability of electric motor is established.Influences of all factors on pump shaft power being considered completely; power spare coefficientsof motor are calculated in three kinds of heads (changing and unchanging), two kinds of dirty-outconditions. Electrical motor power spare coefficients should be chosen as 1.20 approx 1.44, 1.11approx 1.19, 1.09 approx.14 respectively when pump heads are 4, 7, 9.5 m. The results mean much toreasonable choose of electrical motors in large pump stations, increasing reliability of pump unitsand saving equipment investment.
文摘By means of the analysis of the internal flow within inlet passage of large pumping sta-tion, an analysis of 3-D direct boundary element for the flow has been presented on the potentialflow assumption, and a calculation and an experimental proof for the inlet passage of 30 angle-type axial pumping station have been made. Based on the analysis of the calculations and theexperiments, the calculation method is feasible and believable.