EFFECT OF MATERIAL TYPE AND INTERNAL HEAT GENERATION ON TEMPERATURE DISTRIBUTION IN CONVECTIVE HEAT TRANSFER

Abstract

This study investigates the thermal behavior of aluminum, copper, and stainless-steel heat-generating configurations under different geometrical and convective conditions using computational fluid dynamics (CFD). The analysis focuses on the combined effects of thermal conductivity, heat generation, characteristic length, and convection regime on the resulting temperature distribution. A back-calculation procedure was employed to obtain comparable convective heat-transfer coefficients and to reconcile differences in the thermal boundary conditions applied in the independent simulations. The aluminum and copper configurations were subjected to natural convection, yielding convective coefficients of approximately 1.16 and 4.55 W/m²·K, respectively, while the stainless-steel configuration operated under forced convection with a coefficient of approximately 20.4 W/m²·K. Although stainless steel has the lowest thermal conductivity, its smaller characteristic radius and stronger forced-convection condition resulted in the lowest back-calculated maximum temperature, approximately 380.1 K. In contrast, the aluminum and copper cases exhibited maximum temperature differences of 86.56 K and 44.00 K, respectively. The Biot numbers for all three configurations were below 0.1, indicating that internal conduction resistance was negligible relative to convective resistance for the investigated geometries. The analysis demonstrates that the temperature response cannot be attributed to material thermal conductivity alone; instead, geometry and convective boundary conditions substantially influence thermal performance. These findings emphasize the importance of establishing consistent thermal boundary conditions when comparing the effects of different materials in CFD-based thermal analyses.