非线性壁板颤振计算的子循环预测校正方法研究

Nonlinear panel flutter computation with subcycling and predict-correct scheme

为了解决流固耦合问题中弱耦合计算方法存在的滞后误差引起计算发散的问题,将子循环方法与预测校正方法相结合,使用有限元方法求解壁板动力响应,使用Fluent求解受扰动的流场,使用基于拉伸弹簧与扭转弹簧的动态网格方法更新流场网格,分析了弹性壁板在超声速气流作用下的非线性动力响应,结果表明此方法能准确预测壁板颤振的响应特性,计算稳定性优于弱耦合方法,可以保持长时间计算结果的稳定性.

Weak coupling scheme in fluid-structure interaction introduces lag error which results in divergence of computation. To eliminate the error and enhance computing efficiency,subcycling and predict-correct scheme were combined and applied to the supersonic nonlinear panel flutter problem. Dynamic response of the panel was simulated with finite element method, while the geometric nonlinear effect caused by large deflection of the panel was considered. The fluid flow disturbed by panel vibration was computed with Fluent, which has the ability to calculate the governing equations with geometry conservation law. It is demonstrated that the subcycling predict-correct scheme is able to eliminate the lag error of weak coupling and keep the long running time of computation stable.