论文部分内容阅读
空化与空蚀是影响水电站水轮机安全与经济运行的关键因素.为研究不同翼型结构下绕流翼型流场的性能,首先以无孔翼型为研究对象,采用RNGκ~ε湍流模型和欧拉多相流模型中的Mixture模型,对其绕流流场进行数值模拟.由流场内的静压力、动压力、液相和气相体积分数等参数的分布可知,流体绕流无孔翼型过程中发生空化的位置主要在翼型上方,故选择在翼型易发生空化部位打微孔,在单相流的条件下,对具有不同微孔数目的翼型绕流流场进行数值模拟.结果表明:在翼型上打孔后,绕流翼型的流场发生了改变.随着翼型上微孔数目的增加,在翼型上方的湍动能的数值逐渐降低,翼型上方的低压区域的面积减少,而低压区内的压力值明显增加,这将有助于改善绕流翼型流场的空化性能,降低空化和空蚀发生的风险.
Cavitation and cavitation are the key factors that affect the safety and economic operation of hydroelectric power stations.In order to study the performance of the flow field around the airfoil with different airfoil structures, firstly, the non-porous airfoil is taken as the research object and RNGκ-ε turbulence model and Euler multiphase flow model is used to simulate the flow field around the flow field.The static pressure, dynamic pressure, liquid and gas volume fraction and other parameters in the flow field show that the flow around the flow non-porous wing Type cavitation occurs mainly in the airfoil above the location, it is easy to choose the airfoil in the airfoil microphotomagnetism, under the conditions of single-phase flow, with a different number of microporous airfoil around the flow field Numerical simulation results show that the flow field around the airfoil changes when the airfoil is drilled.With the increase of the number of airfoils on the airfoil, the value of the turbulent kinetic energy above the airfoil decreases gradually, and the airfoil The area of the lower pressure region decreases and the pressure in the lower pressure region increases significantly. This will help to improve the cavitation performance of the flow around the airfoil and reduce the risk of cavitation and cavitation.