Wecombined the 3D lattice Boltzmann method (LBM) with the immersed boundary method (IBM) to study the flow physics induced by an elastic rectangular container undergoing harmonic oscillations surrounding a viscous fluid. We proposed a semimicroscopic expression for the drag force to compute the hydrodynamic forces at the boundary nodes. An analytical deformation solution was used based on a thin plate elastic deformation theory to calculate the displacement experienced by the boundary. The numerical simulation results. All the results on figure axes, in this article, are displayed in lattice units. based on the proposed method agreed with the theoretical predictions for channel flow with stationary boundary. The oscillating boundary simulation exhibits the expected flow pattern in line with theory.