Proposed research will improve the accuracy and efficiency of numerical simulations in unbounded domains. Investigations in two important areas of fluid dynamics are pursued. The first is the development of absorbing boundary conditions based on the Perfectly Matched Layer (PML) technique for Large Eddy Simulation (LES) of turbulent flows. Following recent successes of extending the Perfectly Matched Layer methodology to the nonlinear Euler and Navier-Stokes equations, further development of the PML technique for Large Eddy Simulation of turbulent flows is proposed. Formulations of absorbing equations for LES, as well as other turbulent flow simulation, such as the time-dependent Reynolds Averaged Navier-Stokes (RANS) simulations, are proposed. The second area of research is the development of non-reflecting boundary conditions for numerical schemes for the Boltzmann-BGK equation in gas kinetic theory. Proposed work will develop, analyze and implement the absorbing boundary condition based on the Perfectly Matched Layer methodology. Implementation and analysis of PML absorbing boundary condition in the Lattice Boltzmann Method will also be carried out in proposed research.
Due to the ubiquity of non-reflecting boundaries and the importance of Large Eddy Simulation in the computational studies of complex turbulent flows, proposed work will have a direct impact on the quality and efficiency of a broad class of numerical simulations in computational fluid dynamics and computational acoustics, such as in the reduction of airframe and jet noises, in studies of turbulent combustion in reactive flows, and in numerical models for weather predictions. The PML for the Boltzmann-BGK equation developed in proposed research is applicable to a diverse field of scientific investigations that employ the kinetic theory, such as multiphase and multi-component flows, microfluidics in nanotechnologies, particle suspensions and microflows in micro-electro-mechanical systems (MEMS).
