化工轴流泵的非均匀导叶布置

化工轴流泵的工作介质特性使其不便设置导轴承，导致泵转轴缩短，叶轮出口至弯管进口之间只有一段很短的垂直空间，在该空间采用常规导叶布置会恶化水力性能，而化工泵中通常不设置导叶的做法又会使叶轮出口圆周速度分量对应的能量在流道中逐渐损耗。为提高机组效率，采用计算流体力学(CFD)方法分析了均匀布置导叶时的流场特点，发现导致水力性能恶化的原因，提出非均匀导叶布置方案，并进行了数值模拟及对比。结果表明，合理的非均匀导叶布置方案能有效改善装置水力性能。

NON-UNIFORM DIFUSSION VANE ASSEMBLY IN CHEMICAL AXIAL PUMP

Usually chemical axial pump doesn't mount diffusion vane because the distance between impeller and elbow is too short. But this manner would waste energy greatly because the kinetic energy associated with circular velocity at impeller outlet will dissipate gradually in flow passage. In order to increase the unit efficiency, computational fluid dynamics method is adopted to explore the internal flow characteristics for different diffusion vane assemblies. The mechanics is studied, which can explain why hydraulic performance becomes deteriorative when the normal diffusion vane is installed in chemical axial pump. Numerical simulation results indicate that the non-uniform diffusion vane assembly can optimize the unit hydraulic performance effectively.