Abstract:

In the paper, the three dimensional,time dependent,incompressible Navier Stokes equations are numerically solved by the compact finite difference and Fourier spectral hybrid method.A third order mixed explicit implicit fractional step scheme is here employed for the time discretization.The space discretization is implemented using the Fourier spectral expansion and high order compact finite differences.A theoretical model of the symmetric single coherent structure in the wall region of turbulent flow is proposed,utilizing the idea of resonant triad in the theory of hydrodynamic stability.The evolution of the model is numerically studied by the numerical method.The obtained Reynolds stress distribution and the process of the formed strong shear layer are in reasonable agreement with experimental results.

Key words: the wall r egion of t ur bulent flow, numer ical simulation, single coher ent structur e