Numerical investigation of fluid flow past a square cylinder in mixed convective flow regime

Abstract

In current study the numerical experiments have been conducted to elucidate the role of Richardson number and free-stream orientations on the flow dynamics and aerodynamic parameters for the conditions (Re = 140, 0 ⩽ Ri ⩽ 1.2, 0o ⩽α ⩽ 45o, ϕ = 0oand Pr = 0.71). The flow around a heated square cylinder is assumed to be two-dimensional. Also the flow is unsteady, incompressible, viscous and laminar unconfined flow. Oberbeck-Boussinesq approximation is utilized to consider the effects of buoyancy. To discretize the momentum and energy equations finite difference method is employed. Implicit pressure correction scheme is utilized to solve the equations. The flow is found to be unsteady periodic flow for the selected range of parameters except at α=0º and 0.4 ⩽ Ri ⩽ 1.2. The heat transfer rate is observed maximum from the front face(s) of square cylinder. Mean lift coefficient at α=0º is zero for every Richardson number chosen. For chosen free-stream orientations mean lift coefficient is zero at Ri = 0.0. Mean drag coefficient increases with increasing Reynolds and/or Richardson numbers.