基于翼剖面改型的空化抑制

为提高水翼抗空化的性能,对二维翼型的吸力面外形进行适当改造。首先通过数值计算对稳态无空化流场和稳态空化流场进行模拟,计算所得的吸力面压力系数与实验值吻合良好,验证了模型的可行性。在此基础上,采取基于阻碍回射流从而控制空化的思路,在翼型吸力面上设置微小方形凸起,并提出设置拱弧的新方案。通过对原翼型及两种改型的空化流场瞬态模拟,对比了不同时刻各模型气体体积分数云图所反映出的翼面空化程度差异。计算结果验证了阻流体对云状空化的抑制作用,同时表明设置拱弧阻流体的效果比方形阻流体好。

Cavitation Control of a 2-D Hydrofoil Under Section Reshaping

To optimize the cavitation performance of the hydrofoil,some reshaping measures were applied properly on the suction side.In numerical modeling,the 2-dimensional hydrofoils with and without cavita tion in uniform flow were simulated respectively,and those results of the pressure coefficients on the suc tion coincided well with the experimental data.Consequently,the modeling reliability was confirmed.It was assumed that the interruption of the re-entrant jet can suppress the cavitation.Based on the model,a tiny rectangular obstacle was set on the hydrofoil section.And the amendment,which set a vaulted obsta cle instead,was presented.By having instantaneous cavitating flow simulation of the prototype and the two remodelers,the differences were acquired in comparison of the vapor volume fraction contours,which indi cated the intensity of the cavitation.The obstacle’s function was validated in cavitation control,and the vaulted one was proved much better.