Convergence Manufacturing System Engineering (Green Process and Energy System Engineering), University of Science & Technology, Daejeon, 34113, South Korea.
Carbon Neutral Technology R&D Department, Korea Institute of Industrial Technology, Cheonan, 31056, South Korea.
Sci Rep. 2023 Mar 1;13(1):3468. doi: 10.1038/s41598-023-30511-4.
Inlet flow direction significantly affects the hydraulic performance of an axial-flow pump. Usually, the research papers ignore this phenomenon, resulting in discrepancies between simulation and experimental results. This study examines the influence of inflow direction in five cases (0%, 5%, 10%, 15%, and 30% pre-swirl intensities) to determine the relationship between the pre-swirl intensity and the hydraulic performance of the axial-flow pump. Based on this, changing the setting angle of the inlet guide vane (IGV) is proposed and thoroughly investigated to reduce the effect of inflow direction. In this study, the influence of clearances in IGV blades on hydraulic performance is also investigated in detail. Numerical simulations are performed using ANSYS-CFX and a shear stress transport reattachment modification (SST k-[Formula: see text]) turbulence model with small y+ values at all walls. Specifically, the hydraulic performance curves and internal flow characteristics, including contours and streamlines, are assessed and analyzed. The inflow direction significantly impacts the hydraulic efficiency of the axial-flow pump. Increased pre-swirl intensity causes more loss in the IGV passage. The internal flow field and performance are not affected by the clearance at the hub and shroud of the IGV. However, the tip clearance of the impeller causes a decrease in hydraulic efficiency due to the tip leakage vortex. By adjusting the setting angle of the IGV, the efficiency and head gradually increase from a negative to a positive setting angle. Additionally, 30° is considered the critical setting angle for IGV.
进口流动方向对轴流泵的水力性能有显著影响。通常，研究论文忽略了这一现象，导致模拟结果与实验结果之间存在差异。本研究考察了五种情况下（0%、5%、10%、15%和 30%预旋强度）进口流动方向的影响，以确定预旋强度与轴流泵水力性能之间的关系。在此基础上，提出并深入研究了改变进口导叶（IGV）安装角的方法，以减小进口流动方向的影响。本研究还详细研究了 IGV 叶片间隙对水力性能的影响。采用 ANSYS-CFX 进行数值模拟，采用剪切应力输运再附修正（SST k-[Formula: see text]）湍流模型，所有壁面的小 y+值。具体评估和分析了水力性能曲线和内部流动特性，包括轮廓线和流线。进口流动方向对轴流泵的水力效率有显著影响。预旋强度的增加会导致 IGV 通道中的损失增加。IGV 的轮毂和叶栅间隙不会影响内部流场和性能。然而，叶轮的顶部间隙会由于顶部泄漏涡而导致水力效率降低。通过调整 IGV 的安装角，可以使效率和扬程逐渐从负安装角增加到正安装角。此外，30°被认为是 IGV 的临界安装角。
