Towards Large Eddy Simulations of Turbulent Drag Reduction Using Sinusoidal Riblets
نویسندگان
چکیده
A new modification to the drag reduction method using riblets is proposed, which consists of adding a sinusoidal variation to the riblet shape in spanwise direction. It is anticipated that more significant drag reduction will be achieved with sinusoidal riblets due to an oscillatory spanwise component added to the mean flow. First, Large Eddy Simulations of conventional riblet geometry consisting of straight riblets are conducted in order to validate the numerical method to be used for computational investigation of sinusoidal riblets. Summary of the previous findings on straight riblets is reported and illustrated by the results of the current simulations. Second, laminar computations of the sinusoidal riblets are documented and analyzed. Key–Words: Drag Reduction, Riblets, Large Eddy Simulations, Turbulence, Boundary Layer
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