The study of heat transfer by convection and radiation in laminar incompressible fluid flows at low Prandtl numbers is a significant area of research in thermodynamics and fluid mechanics. Heat transfer in such systems is characterized by the complex interplay of two primary mechanisms: convection, which involves the transfer of heat due to the movement of fluid particles, and radiation, which is the transfer of heat through electromagnetic waves. The Prandtl number, a dimensionless quantity that relates the relative thickness of the momentum and thermal boundary layers, plays a crucial role in determining the heat transfer characteristics of fluids. In fluids with a low Prandtl number, such as liquid metals or molten salts, thermal diffusion is much faster than momentum diffusion, leading to distinct flow behaviors compared to fluids with higher Prandtl numbers. The combined effect of convection and radiation on heat transfer is particularly important in high-temperature systems, such as those encountered in heat exchangers, chemical reactors, and power plants. This research aims to explore the interactions between convection and radiation in laminar fluid flows, providing a comprehensive understanding of heat transfer mechanisms in low Prandtl number fluids. By employing analytical, numerical, and experimental techniques, this study investigates the impact of various parameters, including fluid velocity, temperature distribution, and Prandtl number, on both convective and radiative heat transfer. The findings will contribute to optimizing thermal management in systems relying on low Prandtl number fluids and advance the theoretical understanding of combined heat transfer mechanisms

Heat Transfer, Convection, Radiation, Laminar Flow, Low Prandtl Number, Fluid Mechanics, Thermal Diffusion, Boundary Layer, Fluid Flow, Thermal Management, High-Temperature Systems, Numerical Modeling, Heat Exchangers, Power Plants

The study of heat transfer by convection and radiation in laminar, incompressible fluid flow at low Prandtl numbers provides valuable insights into the complex interplay between fluid dynamics, temperature distribution, and radiative heat flux. The main findings of the study emphasize the critical role of temperature gradients, Prandtl number, and radiative properties in influencing the heat transfer characteristics of fluids. The results of the numerical simulations confirm that for low Prandtl numbers, the thermal boundary layer is relatively thick, indicating that thermal diffusion is the dominant process in heat transfer. As the Prandtl number increases, the heat transfer efficiency improves due to the increased momentum diffusivity. Radiative heat transfer is shown to have a significant impact on the overall heat transfer rate, particularly in systems with high temperature gradients. The inclusion of radiation leads to a marked increase in the Nusselt number, which signifies an enhanced heat transfer rate due to the combined effects of conduction and radiation. Moreover, the study illustrates that the buoyancy forces induced by radiation contribute to a reduction in the fluid velocity near the surface, which ultimately influences the skin friction coefficient. The results also highlight the contrasting effects of suction and injection, with suction leading to an increase in the heat transfer rate and injection reducing it due to the altered fluid dynamics at the surface. This study provides a comprehensive understanding of the role of convection and radiation in laminar fluid flow, which is crucial for numerous engineering applications where thermal management is essential. The findings are particularly relevant for industries dealing with high-temperature fluids or processes that involve radiation, such as material processing, heat exchangers, and energy systems. In conclusion, the research underscores the importance of considering both convective and radiative heat transfer mechanisms in fluid flow analysis. The results presented offer a deeper understanding of the factors affecting heat transfer in such systems, paving the way for more efficient designs in thermal management applications. Future work can extend this study to include more complex fluid behaviors, such as non-Newtonian fluids, and explore the effects of radiation in turbulent flows and varying geometries

Vijay Kumar Yadav and Jitesh Kumar Singh (2025). Analysis of Heat Transfer Mechanisms by Convection and Radiation in Laminar Flow of Incompressible Fluids at Low Prandtl Numbers. International Journal on Emerging Technologies, 16(2): 51–56