研究了一种气动力(热)/结构耦合的高超声速机翼热颤振的时域数值分析方法.研究目的是分析结构内部温度梯度对结构固有特性的影响机制和结构发生颤振的规律.采用非定常计算流体力学耦合结构传热的算法,获得结构的瞬态温度场；通过有限元计算得到瞬态温度场不同时刻下的热结构模态；利用结构模态叠加法建立结构动力学模型,结合Volterra级数建立的非定常气动力模型进行气动/结构耦合计算获得颤振动压.对马赫数为5、高度13 km的一小展弦比机翼进行了颤振分析.验证了该方法的可实现性.研究表明,随着温度梯度的增大结构固有频率减小,颤振动压最小值发生在结构主频率差值最小处.%A numerical method to analyze the flutter of hypersonic wing by coupling aerodynamics (with thermal transmittance) with structural dynamics in time domain is studied in this paper. The aim is to analyze the effect of the inner temperature gradient on structural intrinsic properties and on flutter. The algorithm coupling unsteady computational fluid dynamics with thermal transmittance was used to get transient thermal field; the finite element method was used to get the modes of the transient thermal field at different instants; the structural dynamics model based on modal superposition was coupled with the unsteady aerodynamic model based on Volterra Series to get the flutter dynamic pressure. A low-aspect-ratio wing was analyzed at Mach 5, 13 km high. The implementability of this method was verified. Results show that the modal frequencies decrease with increasing temperature gradient and the minimum flutter dynamic pressure is at minimum difference between any two main mode frequencies.
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