The present procedure is essentially a combination of automatic point creation, advancing-front point placement, and connectivity optimization schemes. The overall procedure uses efficient local operations which are applied repetitively to produce a global effect. A valid grid is maintained throughout the grid generation process. This allows the grid to serve as an efficient means of searching with the simple data structure. It also provides an efficient way to smoothly distribute the point spacing. Point distribution is controlled by a point distribution function, which is interpolated from the initial boundary point spacing. An automatic point creation scheme is used wherein points are generated using advancing-front type placement. Connectivity for these generated points is initially obtained by directly subdividing the elements which contain them, without regard to element quality. This connectivity is then improved by swapping elements until a complete field grid is generated with a desired point distribution. The generated grid was then improved using double precision and optimizing the cell’s aspect ratio for viscose flow. Some cases were shown.
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View of grid for a circle.
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View of grid for NACA4424 airfoil.
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Close up view of boundary layer grid for leading edge of NACA0012 airfoil.
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View of grid for naca0012 airfoil.
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Close up view of
grid for leading edge of NACA0012 airfoil.
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Close up view of
grid for trailing edge of NACA0012 airfoil.
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View of grid for high lift
device (airfoil and flap).
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Near view of grid around of flap.
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Close up view of grid around of flap.
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