A Coupled DNS/Monte-Carlo Solver for Dilute Suspensions of Brownian Fibres in Turbulent Channel Flow
A Direct Numerical Simulation (DNS) of turbulent channel flow of dilute suspensions of small, Brownian fibres in a Newtonian solvent is presented. The DNS investigates the potential of drag reduction under situations, where no internal elasticity of the additives is present. The DNS is solving the microscopic equations for the suspended fibres and couples the resulting stresses into a (macroscopic) DNS of the solvent. The microscopic equations for the conformation of the fibres as well as the resulting stresses are derived by the rheological theory of dilute suspensions of Brownian particles in Newtonian solvents. These equations are solved by a Monte-Carlo method. First results show a dramatic reduction of the Reynolds shear stress. However, only a mild reduction of the drag is observed because the fibres generate considerable shear stress components at the wall at the configuration chosen.
KeywordsShear Layer Direct Numerical Simulation Separation Bubble Separation Zone Spanwise Direction
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