再入飞行器振动环境工程预示方法

目的为再入飞行器振动环境设计提供方法支撑,并为结构设计和地面环境试验条件制定提供载荷输入。方法分析再入飞行器振动环境主要特征及其诱导因素,结合飞行试验实测振动数据研究小攻角对飞行振动环境的影响规律,辨识出脉动压力与动压、马赫数以及攻角的关系式。在传统脉动压力预测方法基础上,建立涉及攻角影响的再入飞行均方根脉动压力预测模型,并给出再入振动环境工程预示方法。结果构建模型计算的脉动压力变化趋势与实测振动量值变化趋势基本一致,辨识出来的脉动压力与攻角、动压以及马赫数之间的关系式是基本合理的。结论基于实测数据及脉动压力特性建立了再入飞行器振动环境工程预示模型,结合实测振动数据和气动载荷数据可预测出再入飞行器振动环境,能够实现再入飞行器振动环境载荷的精细化设计,并为结构设计提供载荷输入。

Engineering Prediction Method of the Vibration Environment for Re-entry Vehicle

This paper is to provide method support for the vibration environment design of the re-entry vehicle, and provide load input for the structural design and the formulation of ground environment test conditions. Firstly, the main characteristics and inducing factors of re-entry vehicle are investigated. Secondly, the influence rule of small angle of attack on flight vibration environment is studied based on the measured flight test vibration data. Then, the relations among fluctuating and dynamic pressure, mach number and angle of attack is derived. Based on the traditional fluctuating pressure prediction method, the pulsating pressure RMS prediction model of reentry flight with considering the influence of angle of attack is established. Finally, the prediction method of re-entry vibration environment engineering is presented. The variation trend of the fluctuating pressure calculated by the present model is basically consistent with that of the measured vibration value. The relations among the fluctuating pressure and the angle of attack, dynamic pressure and mach number deduced in this article is basically reasonable. Based on the measured data and fluctuating pressure characteristics, the vibration environment engineering prediction model of re-entry vehicle is established. With the measured vibration and aerodynamic load data, the vibration environment of re-entry vehicle can be predicted, which can realize the detailded design of vibration environment load for re-entry vehicle. It can also provide load input for structural design.