Boundary layer transition model

Data processing: structural design – modeling – simulation – and em – Simulating nonelectrical device or system – Fluid

Reexamination Certificate

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C703S002000, C703S006000, C073S432100, C244S204000

Reexamination Certificate

active

10921486

ABSTRACT:
A method for analyzing performance of an airfoil includes determining: an estimated laminar separation location; a freestream turbulence intensity; a momentum thickness; and a turbulence length scale. Based upon the freestream turbulence intensity, momentum thickness, and turbulence length scale, a first momentum thickness Reynolds number associated with a first estimated laminar/turbulent boundary transition location along the airfoil is determined. If the estimated laminar separation location is downstream of the first estimated transition, the first estimated transition is used to determine a spatial domain for running a turbulent flow model. If the estimated laminar separation location is upstream of the first estimated transition, a second estimated transition location is used to determine a spatial domain for running the turbulent flow model. The second estimated transition location is determined as a function of a momentum thickness Reynolds number associated with the estimated laminar separation location.

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