在金星浮空气球探测器的部署过程中，浮空气球需要借助降落伞减速在空中完成充气，降落伞-浮空气球组合体的气动阻力是方案设计需要考虑的因素。针对以上问题，本文建立了降落伞-浮空气球组合体流固耦合数值模型。在该模型中，借助ALE（Arbitrary Lagrange-Euler）法对流场进行求解，流体计算网格跟随降落伞-浮空气球组合体运动。利用罚函数方法处理流场与降落伞及浮空气球之间的流固耦合，以及降落伞及浮空气球的结构自接触。采用CV（Control volume）法求解浮空气球内部压力和体积变化。通过设置浮空气球初始内部压力，以压缩的方式获得部分充气状态下的气球外形。浮空气球的浮力通过在气球表面施加随高度变化的压差实现。使用该数值模型，对金星大气环境下部分充气浮空气球伞降过程进行了仿真计算，分析了浮空气球充气量变化对计算结果的影响。计算结果表明：在来流影响下，浮空气球外形随时间发生轻微变化，同时气球存在转动；浮空气球及降落伞阻力随时间大幅振荡，两者振荡频率基本一致，充气量变化对振荡频率无明显影响；随着充气量增加，浮空气球平均阻力增大，降落伞平均阻力基本保持不变；浮空气球不同区域应力由高到低依次为：法兰盘附近及气球褶皱位置、气球顶部充满区域和气球凹陷区域。
In the deployment process of the Venus balloon probe, the balloon needs to be decelerated by the parachute to inflate in the air. The aerodynamic drag of the parachute-balloon combination is a factor that needs to be considered in the scheme design. For this issue, a fluid-structure interaction numerical model is established for the parachute-balloon combination. In this model, the flow field is solved using the ALE (Arbitrary Lagrange-Euler) method, and the fluid mesh follows the motion of the parachute-balloon combination. The penalty function method is used to handle the fluid-structure interaction between the flow field and the parachute and balloon, as well as the structural self-contact of the parachute and balloon. The internal pressure and volume changes of the balloon are solved by the CV (Control volume) method. The partially inflated balloon shape is obtained through compression by setting the initial internal pressure of the balloon. The buoyancy of the balloon is achieved by applying a pressure difference that varies with height on the surface of the balloon. Using this model, simulations are conducted on the process of partially inflated balloon parachute descending in the atmospheric environment of Venus, and the impact of changes in balloon inflation rates on the calculation results is analyzed. The calculation results indicate that the balloon shape undergoes slight changes over time under the influence of the flow field, and the balloon rotates. The drags of the balloon and para-chute fluctuate significantly over time, and their fluctuation frequencies are basically the same. The inflation rate change has no significant effect on the fluctuation frequency. As the inflation rate increases, the average drag of the balloon increases, while the average drag of the parachute remains basically unchanged. The areas of the balloon sorted in order of stress from high to low are as follows: flange fringes and wrinkles of the balloon, the filled area at the top of the balloon, depressed areas of the balloon.
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