降落伞附加质量对开伞载荷的影响研究

Study on the Influence of Added Mass on Parachute Opening Load

摘要: 充气过程中的降落伞外形和体积均发生急剧变化，对其气动性能产生重大影响，同时也使得附加质量及其变化规律的确定十分困难。文章首先基于充气仿真数据得到了降落伞的投影面积、阻力面积和伞衣体积变化规律，然后根据几种常用的工程计算方法得到了不同的降落伞附加质量变化规律，最后结合物伞系统动力学分析模型，研究了附加质量及其变化率对降落伞开伞载荷的影响。结果表明：附加质量计算方法对降落伞的开伞载荷分析具有较重要的影响，采用基于伞衣体积的计算方法较基于阻力面积的计算方法更加合适；附加质量变化引起的反作用力和伞衣阻力是降落伞开伞载荷的主要来源；而且开伞载荷峰值的出现时间与附加质量变化率峰值的出现时间基本相同。上述结果为工程中分析降落伞开伞载荷及其影响因素提供了参考。

Abstract: During the process of parachute inflation, the canopy undergoes significant changes in shape and volume, which greatly affects its aerodynamic performance and makes it difficult to determine the parachute added mass and its rate of change. In this paper, we use simulation data from one parachute inflation to obtain the laws governing the change in projected area, drag area, and volume during the inflation process. We then use several common engineering calculation methods to determine the parachute added mass. Finally, we use a forebody-parachute sys-tem dynamics analysis model to study the effects of added mass and its rate of change on the parachute opening load. Our results show that the method used to calculate added mass has a significant impact on the analysis of parachute opening load, with the method based on canopy volume being more suitable than that based on canopy drag area. The main sources of parachute opening load are the reaction forces resulting from added mass changes and canopy drag, and the peak time of parachute opening load is generally the same as the peak time of added mass change rate. These findings provide a reference for analyzing the factors that influence parachute opening load in engineering.