Variable grid scheme applied to turbulent boundary layers

Theoretical Fluid Dynamics Division 5643, Sandia Laboratories, Albuquerque, New Mexico 87115, USA
Computer Methods in Applied Mechanics and Engineering (Impact Factor: 2.62). 09/1974; DOI: 10.1016/0045-7825(74)90033-4

ABSTRACT A Crank-Nicolson type finite-difference scheme with a nonuniform grid spacing has been interpreted in terms of a coordinate stretching approach to show that it is second-order accurate. The variable grid scheme is applied to a flat plate laminar to turbulent boundary layer flow with a rapidly changing grid interval across the layer. The accuracy of the solution is determined for a different number of intervals and compared to results obtained with the Keller box scheme. The influence of changing the grid spacing on the accuracy of the solutions is determined for one coordinate stretching or grid spacing relation. The use of Richardson extrapolation is also investigated.

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