Mixed convection from an elliptic tube placed in a fluctuating free stream

Flow of Newtonian and Power-Law Fluids Past an Elliptical Cylinder: A Numerical Study

“…This clearly casts some doubts on the validity of the steady-flow assumption up to Re = 90 in an earlier study . Unsteady flow over an elliptical cylinder (aspect ratios 0.5 and 0.6) up to R e ≈ 500 was investigated by Ahmad and Badr . They examined the unsteadiness arising from two sources, namely, the fluctuating imposed flow and the vortex-shedding phenomenon.…”

“…14 Unsteady flow over an elliptical cylinder (aspect ratios 0.5 and 0.6) up to Re ≈ 500 was investigated by Ahmad and Badr. 21 They examined the unsteadiness arising from two sources, namely, the fluctuating imposed flow and the vortex-shedding phenomenon. Aside from the aforementioned studies, which utilized the complete Navier-Stokes equations, Khan et al 22 employed the boundary-layer approximation to develop closed-form analytic expressions for skin friction and heat transfer from an elliptical cylinder.…”

Effect of aiding buoyancy on heat transfer from an isothermal elliptical cylinder in Newtonian and Bingham plastic fluids

“…While the relevant studies on the pure free-and forced convection heat transfer from elliptical cylinders in Newtonian fluids have been reviewed recently [2,3,[6][7][8][9], a cursory examination of the pertinent literature shows that the mixed-convection heat transfer from a horizontal elliptical cylinder has received very little attention even in Newtonian fluids [10][11][12], let alone in power-law or Bingham plastic type non-Newtonian fluids. Indeed, to the best of our knowledge, the currently available three studies [10][11][12] are all related to the cross-buoyancy configuration for a horizontal elliptical cylinder.…”

“…Indeed, to the best of our knowledge, the currently available three studies [10][11][12] are all related to the cross-buoyancy configuration for a horizontal elliptical cylinder. Badr [10] solved the coupled governing momentum and energy equations to elucidate the influence of Grashof number (0 6 Gr 6 1.25 Â 10 6 ), Reynolds number (20 6 Re 6 500), and the angle of attack (0°6 k 6 180°) but for a fixed value of the aspect ratio which corresponds to E = 1.67 and mainly for a fixed-angle of attack, k = 30°on mixed-convection heat transfer in air as the working fluid, i.e., for a constant value of the Prandtl number.…”

“…Limited results showing the effect of k on the streamline patterns were also included. Subsequently, Ahmad and Badr [11] revisited this configuration by studying the influence of fluctuating free stream of air for k = 30°and aspect ratio, E = 1.67, over the range of conditions as Re = 50, 100 and 500 and Grashof number, Gr = 2, 3 and 5 Â 10 4 . The frequency of the far flow field ranged from p/4 to p whereas the amplitude ranged from 0.25 to 1.…”