诱导轮旋转汽蚀数值模拟

旋转汽蚀是诱导轮汽蚀不稳定现象中常见的一种,可导致叶片承受循环载荷,引发轴振动,对涡轮泵工作的可靠性造成威胁.本文对一个3叶片诱导轮进行了考虑汽蚀的定常和非定常流动计算,在特定的汽蚀数范围内,在非定常流动计算结果中观察到了旋转汽蚀现象.然后,对一典型计算结果,分析了旋转汽蚀发生时叶片气穴尺寸以及攻角随时间的变化情况.结果表明,叶片上的气穴尺寸与下游相邻叶片的攻角的变化趋势大致相同,但是在气穴尺寸的最大值点附近的变化趋势相反.此外,在叶片气穴尺寸的一个变化周期内,气穴尺寸的变化率与其攻角的变化趋势不完全吻合.

Numerical simulations of rotating cavitation in inducer

Among various cavitation instabilities in inducers, rotating cavitation is the most common one, which can lead to cyclic loading of the inducer blades and severe shaft vibrations, which in turn can degrade the reliability ofturbopumps. In this paper, steady and unsteady simulations are performed for a three-blade inducer. In unsteady simulations within a certain range of cavitation numbers, the rotating cavitation was found. Then, according to a typical calculation result, the variation of cavity sizes of the blades and attack angles with time when rotating cavitation occurred were analyzed. The results indicate that cavity size on each blade has similar changing trend with the attack angle of the nearest downstream blade, but the changing trend is opposite at the point near maximum value of the cavity size. In addition, within one evolution period of cavity size, the changing rate of cavity size on each blade and changing trend of its attack angle are not completely identical.