基于虚功原理的流固耦合面力和位移传递方法
Load and Displacement Transfer Method Based on Virtual Work Principle for Fluid Structure Interaction

为解决已有力和位移传递方法的额外插值误差问题,提出了一种能量守恒的流固耦合面力和位移传递方法。首先将结构网格、流场网格粘贴为一个整体,然后直接采用流固耦合面处流场网格节点的气动力向量作为这一整体系统的激励。提出的方法没有在结构和流场网格之间插值,所以不会引入额外的插值误差,理论分析表明,该方法能够自动满足能量守恒。采用提出的方法对弹性梁、Agard Wing 445？？6颤振问题进行计算,得到的弹性梁颤振周期与文献结果偏差约为0.5％,机翼颤振流速与实验值的偏差约为1.3％,而已有的传递方法对弹性梁的计算结果与文献的偏差要比该方法高出约0.8％,对机翼的计算结果与实验值的偏差要比该方法高出约1.9％。
To avoid the additional interpolation error of existing load and displacement transfer methods, a new load and displacement transfer method based on energy conservation is developed in this paper. The structure mesh and the flow mesh are jointed to be an integral system. Then the nodal aerodynamic force vector of the flow mesh located on the fluid structure interface is taken as the excitation force for the system. There is no numerical interpolation between the structure mesh and the flow mesh during the load and displacement transfer by the present method, so the additional interpolation error does not exist. Theoretical analysis shows that the present method is conservative in energy. Computations are performed for an elastic beam and the Agard Wing 445？？6, and the calculated flutter period of the beam using the present method deviates from the reported data by 0.5％ and the calculated flutter flow speed by this method for the wing 445？？6 differs from the experimental data by 1.3％. While the computational deviation of the existing transfer method is 0.8％ higher than that of the present method for the beam and 1.9％ higher for the wing