NUMERICAL AND EXPERIMENTAL-ANALYSIS OF COMBINED CONVECTIVE AND RADIATIVE HEAT-TRANSFER IN LAMINAR-FLOW OVER A CIRCULAR-CYLINDER

Flow and heat transfer of a participating medium over a right circular cylinder was investigated experimentally and numerically. Experimenta l results for the total Nu number using combustion products of propane were obtained for Reynolds number 500 and gas temperature up to 1219 K. The length-to-diameter ratio of the cylinder was greater than 10, i n order to simulate two-dimensional conditions. A finite-element metho d was used to solve low Reynolds number flow over a circular cylinder in a radiatively participating medium. Continuity, momentum, energy, a nd an equation for radiative intensity were solved simultaneously. A c onstant property assumption allowed decoupling of the momentum and ene rgy equations. The medium was assumed non-gray and non-scattering, and the intensity field was approximated by the P-1 spherical harmonic me thod for each effective band. Edward's wide band model was used to obt ain the absorption coefficient and the effective band width for each b and. The average and local Nusselt numbers were calculated for Re = 50 0. The numerical results for the average total Nu number are in agreem ent with the experimental data.