The non-dimensional form of Navier-Stokes equations for two dimensional mixing layer °ow are solved using direct numerical simulation. The governing equations are discretized in streamwise and cross stream direction using a sixth order compact ¯nite difference scheme and a mapped compact ¯finite di®erence method, respectively. A tangent mapping of y = ¯ tan(¼³=2) is used to relate the physical domain of y to the computational domain of ³. The third order Runge-Kutta method is used for the time-advancement purpose. The convective out°ow boundary condition is employed to create a non-reflective type boundary condition at the outlet. An inviscid (Stuart °ow) and a completely viscous solution of the Navier-Stokes equations are used for verification of the numerical simulation. The numerical results show a very good accuracy and agreement with the exact solution of the Navier-Stokes equation. The results of mixing layer simulation also indicate that the time traces of the velocity components are periodic. Results in self-similar coordinate were also investigated which indicate that the time-averaged statistics for velocity, vorticity, turbulence intensities and Reynolds stress distribution tend to collapse on top of each other at the °ow downstream locations.

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