CHINESE JOURNAL OF COMPUTATIONAL PHYSICS ›› 2016, Vol. 33 ›› Issue (4): 379-390.

    Next Articles

Numerical Methods for Linear Global Stability of Magnetohydrodynamic Duct Flows

HU Jun1, LIU Chan2, ZHANG Nianmei2, NI Mingjiu2   

  1. 1. Institute of Applied Physics and Computational Mathematics, Beijing 100094, China;
    2. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2015-06-03 Revised:2015-10-08 Online:2016-07-25 Published:2016-07-25

Abstract: Spectral Chebyshev collocation method and high-order FD-q finite difference method are used for global instability analysis of magetohydrodynamic(MHD) duct flows and compared for their merits and drawbacks. Spectral Chebyshev collocation method has faster convergence rate and high-order accuracy, while it needs to construct full general eigenvalue matrix which would consume large memory storage and a great deal of computational cost. High-order FD-q finite difference method adopts modified Chebyshev collocation points as discretization mesh grids based on Kosloff-Tal-Ezer transformation. FD-q method can maintain high convergence rate of mesh grids, and resulted general eigenvalue matrix is very sparse and can be stored with sparse matrix, which greatly reduces computational resource. In contrast to traditional spectral collocation method, non-uniform mesh based FD-q method obtains remarkable progress on computational efficiency, which is further demonstrated by computation of linear optimal transient growth for MHD duct flows.

Key words: magnetohydrodynamic duct flows, linear global stability, linear optimal transient growth, Hunt flows

CLC Number: