稳定性导数计算方法研究

Study of Calculating Stability Derivative

稳定性导数的准确计算对于飞行器的操稳特性具有重要意义。应用计算流体力学(CFD)方法中的非结构化动网格技术建立能够模拟飞行器做周期性俯仰运动的强迫振荡法,以国际动导数标模Finner导弹为验证算例,获得不同马赫数下俯仰力矩系数的迟滞环曲线,进而计算Finner导弹在不同马赫数下的静稳定性导数和动稳定性导数。结果表明:本文计算得到的俯仰静稳定性导数与试验数据非常接近;在亚音速和超音速范围内,动稳定性导数计算结果与试验值很接近,但在跨音速范围内,本文计算结果与试验曲线的规律性一致,但误差较大。

It is of significant importance to calculate the stability derivative accurately for stability and control of an aircraft. Dynamic mesh technology in computational fluid dynamics（CFD） are used to simulate periodic pitching oscillation motion of Finner missile circling around a fixed axis. The hysteresis curve of pitching mo- ment coefficient for the basic model Finner missile is obtained at different Mach number. The static and dynamic derivatives of the missile in different Mach numbers are computed. The results show that the static derivatives are close to test data very much, and so as the dynamic derivatives in subsonic and supersonic speed range. The results in transonic speed range is of a similar tendency to test data, but with a big error.