平面遮挡分析法及其在航天器气动力矩分析中的应用

摘要

针对空间站等复杂构型航天器迎流面积和气动力矩的快速分析问题，提出一种平面遮挡分析法。该方法在与迎流垂直的方向上，选定一个二维投影平面进行航天器组成单元的划分和二维外形信息的定义；通过标志符、差值函数及相关的单元外形边界搜索规则定义和操作，实现迎流面积和遮挡面积的计算。平面遮挡分析法减少了遮挡分析所需使用的航天器外形信息维度，可以提高遮挡分析的效率。然后给出基于该平面遮挡分析法对迎流面积和压心位置进行计算的数学模型，对使用的气动力矩分析模型进行说明。以一个非对称构型的空间站为例，对相应的迎流面积和气动力矩进行仿真计算和对比验证。结果表明，平面遮挡分析法具有较为明显的计算时间优势，同时具备较高的计算精度。%A planar method for obscuration analysis is proposed to analyze and compute the windward area as well as aerodynamic torque of spacecraft with complex configuration,such as space station.In this method,a plane which is perpendicular to the windward direction is chosen as the projection plane,in which a spacecraft system is divided into different units and the outlines of these units are defined.The windward area as well as obscuration area are analyzed and computed through the definition of identifier,difference function and relevant rules of units′edge searching.In this planar obscuration analysis method,less information of the spacecraft outlines is used,thus the efficiency of obscuration analysis can be improved.Then,on the basis of this planar obscuration analysis method,the mathematical models for windward area and pressure center computations are given.In addition,the aerodynamic torque computation model used in this paper is introduced.Taking a space station with asymmetrical configuration as an example,its windward area and aerodynamic torque are computed through simulation and compared with some other simulation results.It’s shown that the planar method for obscuration analysis costs much less time and has relatively high accuracy.