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动导数是飞行器轨道及姿态控制系统设计时的重要参数,对飞行器开环系统受到扰动时振荡的敛散特性起重要作用。在标模验证的基础上开展吸气式内外流一体化飞行器WR-A动态特性分析,采用N-S方程模拟强迫简谐振动的非定常流场,获得了飞行器的直接阻尼导数、加速度导数和旋转导数,并对WR-A外形大振幅振动时的进气道性能参数进行了分析。研究表明,在某些情况下反映流动时滞效应的加速度导数占直接阻尼导数的比例最高可以达到40%以上,而在某些情况与直接阻尼导数符号相反。此外,在动导数研究基础上,采用参数化的动导数概念初步开展了非定常气动参数建模研究。针对WR-A大振幅强迫振动的研究显示,采用所建立的模型预测的气动参数与完全非定常计算吻合较好。
Dynamic derivative is an important parameter in the design of orbit and attitude control system. It plays an important role in the convergent and divergent oscillation of the open-loop system. On the basis of the model verification, the dynamic characteristics of WR-A integrated aspirated inflow and outflow aircraft are analyzed, NS equations are used to simulate the unsteady flow field of harmonic vibration, and the direct damping derivative, acceleration derivative and rotation derivative The inlet performance parameters of WR-A with large amplitude vibration were analyzed. The results show that in some cases, the derivative of acceleration that reflects the flow delay effect can account for more than 40% of the direct damping derivative, and in some cases the opposite sign of the direct damping derivative. In addition, on the basis of the study on the dynamic derivatives, the unsteady aerodynamic parameters modeling has been carried out by using the concept of parametric dynamic derivatives. The research on large-amplitude forced vibration of WR-A shows that the aerodynamic parameters predicted by the established model are in good agreement with the completely unsteady calculations.