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In this paper, the case of the steady two-dimensional flow in a two-sided lid-driven square cavity is numerically investigated by the finite volume method (FVM). The flow motion is due to the top and bottom horizontal walls sliding symmetrically in the opposite direction with equal velocities, UT and UB, obtained through three respective Reynolds numbers, Re1,2=10000, 15000, and 20000. Due to the lack of availability of experimental results in this Reynolds number margin for this type of flow, the problem is first examined by considering that the flow is turbulent with the inclusion of four commonly used RANS turbulence models: Omega RSM, SST k-ω, RNG k-ε and Spalart-Allmaras (SA). Next, the regime is considered being laminar in the same range of Reynolds numbers. A systematic evaluation of the flow characteristics is performed in terms of stream-function contour, velocity profiles, and secondary vortices depth. Examination of the calculation results reveals the existence of a great similarity of the predicted flow structures between the Omega RSM model and those from the laminar flow assumption. On the other hand, the computed flow with the SST k-ω model, the RNG k-ε model, and the SA model reveals a remarkable under-prediction which appears clearly in the size and number of secondary vortices in the near-wall regions. Various benchmarking results are presented in this study.

Nomenclature e -width of the magnetic gap, m; C p -specific heat with constant pressure, J/Kg C°; h -coefficient of heat transfer by convection, w/m 2 C°; K -kinetic energy turbulent; L -lenght of rotor, m; V -axial speed of fluid, m/s; w -angular velocity, rd/s; Nu -Nusselt Number; Pr -Prandtl Number; Ta -Taylor Number; (Ta) m -Taylor Number modified; r e -interior radius of stator, m; r i -exterior radius of rotor, m; λ -thermal conductivity, w/mC°; ν -kinematic viscosity, m 2 /s

We report three-dimensional simulation results of thermal mixing in square T-junction configuration at high Reynolds number. The square T-junction configuration with different channel sizes was studied experimentally at the Department of Mechanical Engineering of Mie University, Japan. The T-Junction was selected as a benchmark for thermal mixing in the ERCOFTAC Workshop held in EDF Chatou, France, 2011. RANS, URANS and SAS simulations were performed with CFD code using finite volume method The comparison shows excellent agreement between SAS and the data.