基于网格测力数据的多体分离轨迹预测方法研究

Multi-Body Separation Trajectory Prediction Based on Grid Force Measurement Data

关键词:  两级分离  网格测力  离线轨迹  气动力数学模型  刚体运动方程

Key words:  Two-stage separation  Grid force measurement  Off-line trajectory  Aerodynamic mathematical model  Rigid body motion equation

摘要:

将基于风洞网格测力试验数据建立的气动力模型与刚体运动方程进行耦合求解，得到多体分离轨迹-时间特性，建立了一种多体分离的离线轨迹预测方法。为了提高气动力模型的预测精度，针对移动最小二乘法（MLS）模型提出一种新的权函数形式，针对Kriging气动力数学模型通过加入样点预处理提出了Kriging-Pre数学模型。研究方法应用于来流马赫数6条件下，某并联两级入轨飞行器标模的分离特性研究。研究表明采用改进的两种气动力数学模型均可有效提高分离轨迹预测精度，得到与CFD以及风洞试验定性一致的结论。验证了本文提出的离线轨迹预测方法可以满足当前多体分离特性定性分析需求，具有较高时效性。

Abstract:

The trajectory time characteristics of multi-body separation were obtained by coupling solution of the aerodynamic model based on the grid test data of wind tunnel and the motion equation of rigid body. A method for off-line trajectory prediction of multi-body separation was established. In order to improve the prediction accuracy of the aerodynamic model， a new weight function was proposed for the moving least square （MLS） model， and a Kriging-pre mathematical model was proposed for the Kriging aerodynamic mathematical model by adding sample point pretreatment. The method was applied to study the separation characteristics of a TSTO parallel two-stage orbiter under the Mach number of 6. The results show that the two improved aerodynamic mathematical models can effectively improve the prediction accuracy of the separation trajectory， and the conclusions are qualitatively consistent with CFD and wind tunnel tests. It was verified that the off-line trajectory prediction method proposed in this paper can meet the current requirements for qualitative analysis of multi-body separation characteristics and has high efficiency.