Linear method for the determination of Newton’s heat transfer coefficient in the gap under conditions of limited convection

This study investigates heat transfer under conditions of limited (undeveloped) convection within a narrow 5 cm gap between a centrally positioned heater and the inner walls of a closed chamber. A simplified approach − the linear method − is proposed for estimating Newton’s heat transfer coefficient, assuming a weak linear dependence on temperature. Experimental data and known convection models were used to verify the method. The convective component obtained using the linear method was compared to experimental values and theoretical bounds, showing that the linear method slightly overestimates but remains within a valid range. Artificial neural networks supported the estimation of steady-state temperatures and voltages. This work is a continuation of earlier research and confirms the practical value of the linear method in constrained thermal environments. Further development of the experimental rig is planned to expand the study.