Forced convection on grey cast iron plate-fins: Prediction of the heat transfer coefficient

The main goal of the present work is to evaluate the convective heat transfer coefficient at the surface of grey cast iron plate-fins. A hybrid numerical/experimental approach was adopted, i.e., temperature was measured at selected points at the fin surface and an inverse problem technique based on optimization was used to obtain the heat transfer coefficients. The direct heat transfer problem was solved numerically using the finite volume method, whilst the optimization problem was resolved based on particle swarm optimization (PSO). Firstly, the temperature dependence is investigated by comparing uniform, linear and parabolic equations for the heat transfer coefficient. The hybrid approach was validated through an energy balance applied to the finned surface. The parametric study was performed by assessing the influence of the fin spacing and flow velocity on the convective heat transfer coefficient: the results indicate that the convective coefficient is enhanced with increasing Reynolds number and fin spacing. Finally, the experimental results for the Nusselt number in the parametric study were condensed into a single new empirical correlation with good accuracy.