降落伞临界开伞速度研究

The Research on the Critical Velocity of Parachute Opening

为了解航天器用降落伞的使用边界,计算降落伞临界开伞速度,文章基于充气体积理论推导了临界开伞速度的理论计算公式,讨论了影响临界开伞速度的因素。研究结果表明,降落伞临界开伞速度与大气密度、织物透气量、伞衣顶部结构透气量成反比;通过伞绳长度增加,影响伞衣充气进气口尺寸提高降落伞的临界开伞速度;降落伞临界开伞速度与伞衣尺寸的关系和降落伞充气过程底边尺寸有关;在降落伞底边尺寸大于某一临界值时,降落伞临界开伞速度与伞衣尺寸成正比;在降落伞底边尺寸小于某一临界值时,降落伞临界开伞速度与伞衣尺寸成反比。文章基于降落伞临界开伞速度与伞衣充气外形尺寸相关这一理论,提出计算收口状态下降落伞的简化充气外形尺寸方法,计算结果与流固耦合仿真结果一致。文章的研究结论可用于评估降落伞的开伞条件,为降落伞设计、应用提供参考。

In order to understand the application boundary of parachute and calculate the critical velocity of parachute opening,the theoretical calculation formula of parachute critical velocity is derived,and the factors affecting the critical velocity of parachute opening are discussed.The results show that the critical opening velocity of parachute opening is inversely proportional to the air density,fabric permeability and crown parachute poriosity.The increase of parachute suspension line and the gores of parachute will increase the critical velocity by affecting the size of parachute inflation inlet.When the bottom size of parachute is larger than a critical value,the critical velocity of parachute opening is proportional to the size of parachute.When the bottom size of parachute is less than a critical value,the critical velocity of parachute is inversely proportional to the size of parachute.The critical velocity of parachute opening is related to the dimension of parachute.Based on this theory,the simplified inflatable dimension of reefing parachute is proposed,and the calculated results are consistent with the FSI simulation results.The research work in this paper can provide reference for parachute design and application.