为了研究初生空化流动形态及其紊流流场结构,采用高速录像技术观察了绕Clark—Y型水翼初生空化的空化形态,应用LDV分别测量了无空化和初生空化条件下的紊流流场分布。结果表明,绕水翼小攻角无分离流动区域的初生空化形态呈游离发夹涡型空泡团结构,但其具有和单泡相同的发展过程;初生空化和无空化紊流流场的速度和紊流强度没有发现有规律性的差异,初生游离型空穴的形成与发展过程,对雷诺平均流场没有显著的影响。
To shed light on the inception cavitating turbulent flow structure, a high-speed video camera is used to visualize the cavitating patterns around a Clark-Y hydrofoil under the inception cavitation condition.The 2D-LDV technique is employed to measure the average turbulent velocity fields in inception cavitating and non-cavitating flow regimes. It is shown that the inception cavitating cavities are generated along with a hairpin-shaped vortex structure in the non-separated flow. The developing process of an inception cavity is the same as an individual cavitation bubble. There is no distinct difference between inception cavitating and non-cavitating turbulent flows. The contribution of the generation and collapse of an individual inception cavity to the average turbulent flow has not been observed.