水下航行体通气超空泡的实验研究

为了研究超空泡的减阻效果,保证在较低流速下生成超空泡,在水洞中开展了水下航行体通气超空泡的实验研究.采用通气的方法在较低水速下(V=7-15 m/s)生成人工通气超空泡,通过改变通气率和弗洛德数,获得了不同条件下通气空泡的长度,给出了通气空泡长度与通气率及弗洛德数的经验公式.研究表明,来流速度不变时,空泡长度随通气率的增加而增加,空泡长度一定时,通气率随弗洛德数的增加而减少;重力场造成了空泡形态的严重不对称,通过比较相同空化数下自然空泡与通气空泡的长度,定量地给出了弗洛德数对通气空泡长度的影响.当Fr=43.74时,重力场对通气空泡长度的影响几乎可以忽略.

Experimental investigation of ventilated supercavity of underwater bodies

In order to explore drag reduction of supercavity and guaranteeing forming supercavity in lower velocity,experiments of underwater bodies forming ventilated supercavity were performed in cavitation tunnel.Supercavity was formed using ventilation method in lower velocity.Changing ventilation volume and Froude number,a series supercavity lengths were obtained in different conditions and experiential formula of ventilated cavity length was presented.Experimental investigation shows that supercavity length increases with ventilation volume increasing at constant velocity,and ventilation volume reduces with Froude number increasing for some a supercavity length.Gravity causes ventilated supercavity serious asymmetry.Comparing vapor supercavity length with ventilated in the same cavitation number,Froude number effecting on ventilated supercavity length was quantified.Gravity effecting on ventilated supercavity length can be ignored at Fr=43.74.