空化器参数对超空泡形成和发展的影响

INFLUENCE OF CAVITATOR PARAMETERS ON FORMATION AND DEVELOPMENT OF SUPERCAVITY

为了探索超空泡的生成机理和形态变化规律,依据其产生方式,进行了自然超空泡高速射弹试验和通气超空泡水洞试验研究．分析了超空泡的生成过程和空化器参数对形成超空泡的临界空化数和通气系数门限值的影响．研究了超空泡形态尺寸变化的特性,空化器直径和线型对自然和通气超空泡的形态尺寸有相类似的影响规律:超空泡尺寸随着空化器直径的增加而增加;在相同条件下,钝头空化器要比圆锥形空化器更容易形成超空泡;相对较小的直径空化器很难形成透明的通气超空泡,其主要原因是自然空化数没有降到足够低．此外,研究表明空化器直径对通气超空泡的细长比的影响较大,这与对自然超空泡形态的影响不相同．最后,对空化器的未来研究发展进行了展望．

Based on the way how to form supercavity, a series of projectile experiments and moderate-speed tunnel experiments were carried out to study the formation and development of the natural and ventilated supercavities in this paper. The processes of forming supercavities were recorded and discussed. The influence of cavitator parameters on the critical cavitation number and critical ventilation coefficient was analyzed. Qualitative features of the supercavity size change were obtained. It is shown that the cavitator diameter and coutour have a similar influence on the natural and ventilated supercavity sizes. Supercavity size increases with cavitator diameter and the formation of supercavity for a blunt cavitator is easier than for a cone cavitator under the same conditions. A cavitator of relatively small diameter might not be able to form a ventilated supercavity, mainly because the natural cavitation number is not small enough. Furthermore, the research shows that the cavitator diameter has an important effect on the fineness ratio of the ventilated supercavity, which is not the same as the natural supercavity. Finally, the perspective future research on cavitators is discussed.