Conjugate natural convection heat transfer in an open-ended vertical concentric annulus

This paper is concerned with the steady conjugate heat transfer problem in vertical open-ended concentric annuli under the laminar natural convection flow regime. A finite difference technique has been used to solve the governing equations, with the outer surface of the outer tube wall being isothermally heated while the inner surface of the inner tube is kept adiabatic. Numerical results are presented for a Newtonian fluid of Pr = 0.7 in a fluid annulus of radius ratio 0.5. We present the effect of solid-fluid conductivity ratio on the induced flow behavior and some engineering parameters, such as the heat absorbed and the mixing-cup temperature.