Thermal analysis of a rotary regenerator with fixed pressure drop or fixed pumping power

Heat transfer in a rotary regenerator subject to constant pressure drops or pumping power constraints was examined. The fluid flow and the convective heat transfer coefficient were determined from correlations. These results were used as inputs for a numerical solution which was applied to evaluate the regeneratorʹs thermal performance. A scale analysis was conducted to determine the order of magnitude of optimal porosity and maximum heat transfer. This analysis suggests the best scales to present heat transfer and heat capacity rate in dimensionless form. It was found that, for a given dimensionless pressure drop or pumping power, there is a level of porosity that maximizes the heat transfer rate. The scale analysis of power law predictions showed good agreement with numerical results. Diagrams are presented with curves of optimal operating conditions for the prescribed constraints for typical rotary regenerators with both streams under the laminar flow regime.