中文摘要：

为深入研究绕带空化器回转体的空化流场结构,采用试验和数值模拟的方法对带不同尺度空化器回转体的空化流动进行了研究。运用高速全流场流动显示技术获得了不同空化数下绕回转体的空泡形态,运用粒子图像测速技术（DPIV）测量了相应工况下流场的时均速度和时均涡量分布。研究结果表明：空化器尺度对绕回转体空化流动有重要影响,对于自然空化,不同尺度空化器初生空化数不同,空化器越大越有利于空化的产生,并有利于空泡的发展;对于通气空化,在相同通气率下,绕小尺度空化器回转体产生的空泡长度大于绕大尺度空化器回转体的泡长,且绕小尺度空化器回转体容易达到稳定的超空泡状态。这是由于在大空化器后部流动分离明显,存在更加复杂的漩涡运动,从而不容易产生稳定的空泡。在相同通气率和傅汝德数下,绕带不同空化器的回转体形成的空泡形态不同,空泡的脱落方式和周期也不同。

英文摘要：

The structure of cavitating flows around an axisymmetric body with different size cavitators is studied by experimental and numerical simulation methods. Cavity shapes around the body were obtained by a high-speed video camera in different cavitation numbers,and the time-averaged velocity,and time-averaged vorticity distributions were obtained by a digital particle image velocimetry（ DPIV） system. The results show that the cavitator diameter has important influence on cavitating flows around the axisymmetric body. The inception cavitation number varies with the cavitator diameters in natural cavitation conditions. The bigger the cavitator diameter is,the larger the inception cavitation number is,and the more favorable to the cavity development. In ventilated cavitation conditions and the same ventilated rates,the cavity length around the axisymmetric body with a small cavitator is bigger than that of the axisymmetric body with a large cavitator. However,the supercavitating state is easily obtained in a lager cavitation number around the axisymmetric body with a small cavitator because the flow separation is obvious in the rear of large cavitator and there exists a more complicated vortex movement,which is not conducive to the formation of steady large cavity. At the same ventilated rate and Froude number,the cavitation shapes around the axisymmetric body with different diameters are different,and the fall-off mode and the period are different.