高海拔地区气压环境对高速水流空化特性的影响

为定量评价高海拔地区的低气压环境对水流空化特性的影响程度,通过理论计算单气核临界压强在不同气压条件下的变化,分析单气核临界压强变化对初生空化数的影响程度,并进行不同海拔高程下水流空化数的敏感性分析。研究成果表明:低气压环境下,气核初生空化数和水流空化数均减小,但水流空化数减小的程度远远大于初生空化数减小的程度,其他条件相同的前提下,高海拔地区的高速水流空化空蚀风险增大。研究结论可为高海拔地区高速水流的空化空蚀设计和评价提供参考。

Influence of Atmospheric Pressure on Cavitation Characteristics of High Velocity Flow at High Altitude

To quantify the influence of low pressure environment at high altitude on the cavitation characteristics of water flow, single gas nucleus critical pressure under different pressure conditions was theoretically calculated. The influence degree of single gas nucleus critical pressure on the nuclear incipient cavitation number was analyzed, and the sensitivity of flow cavitation number at different elevations was evaluated. Research results showed that, in low pressure environment, both gas nuclear incipient cavitation number and water flow cavitation number decreased, but the water flow cavitation number decreased much more intensively than gas nuclear incipient cavitation number did. On the premise that other conditions are the same, the cavitation erosion risk of high velocity flow is correspondingly high in high-altitude area. The research conclusions provide reference for the design against and evaluation of cavitation erosion of high speed flow in high altitude area.