Heat Transfer Correlations for Thermally Developing Flow in Rectangular Micro-Channels Subject to Four-Sided and Three-Sided H1 Boundary Conditions

In this study, heat transfer to laminar hydrodynamically fully developed flow in the thermally developing region of rectangular micro-channels is analyzed for four-wall and three-wall circumferentially uniform temperature and axially uniform heat flux (H1) boundary conditions. The temperature and wall heat flux distributions are solved numerically and used to calculate the local average Nusselt number. Based on the numerical results, new correlations capable of predicting heat transfer in the thermally developing region continuously into the fully developed region are developed. The correlations are compared with other correlations and available experimental data, and show good agreement.