基于反馈定理的IB-LB方法(英文)

格子波尔兹曼方法(Lattice Boltzmann method,LBM)和浸入边界方法(Immersed boundary method,IBM)皆为近年来发展的可替代Navier-Stokes(N-S)方程求解复杂流体力学问题的数值模拟方法。本文采用浸入边界-格子波尔兹曼方法(IB-LBM),将IBM作为一种边界处理格式应用到LBM中,模拟了静止单圆柱及并排双圆柱绕流,与文献对比结果吻合良好,证明该方法具有模拟复杂边界物体绕流的能力。与采用虎克定理、直接力法计算体积力项的传统方法不同的是本方法运用反馈定理,即采用流场和流场内物体之间的速度、位移反馈来计算体积力项,使得该方法易于实施并具有优良的并行性。

NOVEL IMMERSED BOUNDARY-LATTICE BOLTZMANN METHOD BASED ON FEEDBACK LAW

The lattice Boltzmann method(LBM)and the immersed boundary method(IBM)are alternative,computational techniques for solving complex fluid dynamics systems,and can take the place of the Navier-Stokes(N-S)equation.This paper proposes a novel immersed boundary-lattice Boltzmann method(IB-LBM)based on the feedback law.The method uses the immersed boundary concept in the LBM framework to capture the coupling between a body with complex geometry and a uniform fluid,Then,the flows around a stationary circular cylinder and two circular cylinders in a side by side arrangement are simulated by using the method.Results are agreed well with the benchmark data,so,the capability of the method for complex geometry is demonstrated.Different from the conventional IB-LBM,which uses the Hook’s law or the direct forcing method to compute the interaction force,the method uses the feedback law—the feedback of velocity field and displacement information to calculate the force,thus ensuring the method has advantages of easy implementation and full parallelism.