Title of the Paper: Note on the Turbulence Transition Threshold of a Buoyancy-Driven Flow over an Isothermal Vertical Wall
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Authors: Catalin Popa, Stéphane Fohanno, Guillaume Polidori
Abstract: The integral formalism has been developped in an attempt to predict the mathematical transition threshold from laminar to turbulent regimes in a free convection boundary-layer flow adjacent to an isothermal vertical wall and also to gain a better understanding in the prediction of the turbulence mechanism. The transition threshold is approached herein as the intersection of the two fully developped laminar and turbulent flow regimes. As earlier shown for the uniform heat flux condition, the transition for the isothermal wall condition is also Prandtl number dependent and occurs differently depending on whether the dynamical or thermal viewpoints are considered. A change in the transition threshold behaviour is observed at Pr = 20.
Keywords: Free convection, Laminar and turbulent regimes, Transition threshold, Vertical wall
Title of the Paper: Approximate Analytic Solutions for Mixed and Forced Convection
Heat Transfer from an Unsteady No-Uniform Flow past a Rotating
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Authors: Kenzu Abdella, Felicia Magpantay
Abstract: Presented in this paper is an analytic approximation to the thermal-fluid problem involving mixed and
forced convective heat transfer from a rotating isothermal cylinder placed in a non-uniform stream shear-flow. The
approximation is obtained using a series expansion of the scaled boundary layer equations in terms of a boundary
layer variable which is directly proportional to the time variable and inversely proportional to the Reynolds number.
Therefore, the resulting approximation is valid both for small time and for moderate and large times for which the
Reynolds number of the flow is sufficiently large.
Keywords: shear-flow, mixed and forced convection, rotating cylinder, boundary layer, viscous flow, laminar.