离心泵输送粘油的水力性能计算

采用CFD程序FLUENT计算了离心泵输送水和粘油时的内部流动和水力性能，重点考察了液体粘度对泵水力性能的影响，并将计算结果与实验数据进行了对比．结果表明，叶片与蜗壳隔舌之间的相对位置对泵水力性能影响很小；叶轮水力效率和水力损失系数分别随着液体粘度的增大而降低和增大，但在个别粘度和流量下，水力性能比输送水时要好；叶轮理论扬程在小流量工况下出现驼峰．计算的泵扬程与实验值接近，存在“扬程突升”现象．该现象是由粗糙的叶轮和蜗壳过流表面，以及液体粘度增高引起的．

Performance computations of centrifugal pump handling viscous oils

By considering water and viscous oils respectively as transported fluids, the performance and internal flow field of a centrifugal pump was investigated numerically with CFD software FLUENT. The effect of liquid viscosity on the pump performance was patieularly addressed. The results were compared with the experimental data. The results showed that the influence of the relative position between the vo- lute tongue tip and the blade trailing edge on the performance is not significant. The hydraulic efficiency decreases and loss of impeller increases with increasing viscosity. The impeller performance is improved at particular viscosity. A peak exists in the impeller theoretical head curves at low flow rates. The pump head estimated with CFD is close to the test data and the ＂sudden-rising head effect＂ exists. A high vis- cosity and a particular level of roughness are responsible for the ＂sudden-rising head effect＂.