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在离心泵开式试验台上 ,对离心泵在不同转速不同输送介质粘度条件下的性能进行了试验研究 ,发现离心泵输送低粘度介质时 ,泵的性能符合相似定律 ,但输送介质粘度较高时 ,性能变化规律存在偏差。对同一台泵 ,输送介质粘度一定 ,各种转速对应的最优工况点的比转速基本相等 ;粘度改变 ,泵的比转速随着改变 ,最佳效率也相应改变。这说明 ,粘性输送时 ,应采用比转速与粘度或能同时兼顾这两种参数的相似准则数来描述离心泵的性能。试验结果表明 ,利用雷诺数Re =Qνopt/d2 ν作为相似准则数 ,能较好描绘输送粘性流体时离心泵性能的相似关系。就试验泵而言 ,当Re≥ 3× 1 0 6 时 ,相似关系基本可以得到满足
Centrifugal pump on the open test bench, the centrifugal pump at different speeds under different media viscosity conditions were studied and found that centrifugal pump delivery of low viscosity medium, the pump performance in line with similar laws, but the transmission medium viscosity higher When the performance changes in the law there is deviation. For the same pump, the viscosity of the conveying medium is constant, and the optimal operating conditions corresponding to various rotating speeds are basically equal to the rotating speed. When the viscosity changes, the specific rotating speed of the pump changes and the optimum efficiency changes accordingly. This shows that viscous delivery, should be used than the speed and viscosity or both parameters can take into account the similarity of the number of guidelines to describe the performance of centrifugal pumps. The experimental results show that using the Reynolds number Re = Qνopt / d2 ν as the similarity criterion, the similarity between the performance of the centrifugal pump and the viscous fluid can be well described. For the test pump, when Re ≥ 3 × 10 6, the similar relationship can basically be met