Relationship between Nusselt and Rayleigh Numbers in Natural Convection

Abstract

When studying heat transfer in laminar or turbulent flow, the aim is to maximize heat transfer, using for example corrugated channels; nanofluids or hybrid nanofluids, etc.; to determine the factors that influence the thermal and hydraulic performance of the used equipment and to determine the relationships that may exist between heat transfer efficiency and these various variables; hence the study of the relationships between these various factors. The findings can be analyzed by using tables, graphs or correlations. The objective of the current paper is focused on the last approach. In addition, we are attempting to determine the influence of the physical parameter Rayleigh number (Ra) on thermal and hydraulic behavior, using the FLUENT calculation code, on the one hand, and to validate the correlation obtained, based on a statistical model, on the other hand. We have also validated that our findings are in excellent accord with those of prior work involving this statistical method.