【摘要】 基于RNG k-ε紊流模型和雷诺时均N-S方程,运用CFD商用大型软件对箱涵式进出水流道立式轴流泵装置进行了三维流动仿真计算及水力特性的优化设计。通过先部分后整体的方法先独自对箱涵式进水流道进行优化计算,而后在整体泵装置上对箱涵式出水流道进行优化计算。进水流道的优化以出口断面流速均匀度和水力损失为目标函数,出水流道的优化则以泵装置效率和水力损失为目标函数。通过数值计算得出,优化后箱涵式进水流道的水力损失由7.52 cm降低到3.49 cm,进水流道出口流速均匀度由42.41%提高到89.11%,进水流道的悬空高度H和进水喇叭管与叶轮间的连接角度α对进水流道水力特性的影响显著,设计时应该重点考虑。箱涵式出水流道的水力损失由87.15 cm降低到76.37 cm,出水流道的设计应重点关注导流墩与出水喇叭管的半径差Δr和出水导流墩的半径R,合适的出水导流墩半径在0.75倍导叶出口直径左右。泵装置模型试验在叶片安放角-4°时,设计工况下泵装置效率达到75.0%,泵装置最高效率为75.67%,高效区运行范围较宽;对比数值计算和模型试验的结果可以发现误差最大处低于5%,整体性能曲线的趋势相对良好,说明数值模拟对于泵装置的优化是合理的,对于实际工程具有指导意义。更多还原

【Abstract】 Based on the RNG k-ε turbulence model and the Reynolds time-averaged N-S equation,the CFD commercial large-scale software is used to simulate the three-dimensional flow simulation and hydraulic performance of the box-carrying inlet and outlet vertical axial flow pump device. The tank culvert inlet flow passage is optimized by the partial and integral method respectively,and then the tank culvert outlet passage is optimized in the integral pump device. The passage is characterized by the velocity uniformity and hydraulic loss of the outlet section,and the outlet flow passage is based on the pumping unit efficiency and hydraulic loss. According to the numerical simulation,the hydraulic loss of the optimized tank-type inlet flow passage is reduced from 7.52 cm to 3.49 cm,and the uniformity of the inlet flow passage of the box-type inlet passage increases from 42.41% to 89.11%. The connection angle α between the inlet horn and the impeller is most sensitive to the influence of the hydraulic characteristics of the inlet runner,and should be focused on the design. The hydraulic loss of the tank-carrying water passage decreases from 87.15 cm to 76.37 cm. The design of the outlet passage should focus on the radius difference Δr between the diversion pier and the outlet trough tube and the radius R of the outlet diversion pier,suitable drainage diversion.The radius of the pier is about 0.75 times the diameter of the vane outlet. When the blade placement angle is-4 degrees,the efficiency of the pump device is 75.0% under the design condition,the maximum efficiency of the pump device is 75.67%,and the operating range of the high efficiency zone is wide; the numerical simulation and model test results can find the minimum error of no more than 5%,the overall performance curve trend is relatively good,indicating that the numerical simulation is reasonable for the optimization of the pump device,instructive for practical engineering.更多还原