Numerical Analysis of Heat Transfer in Pin-Fin Heat Sinks Using Mini-Channel Configurations

Abstract

Pin-fins are widely utilized to enhance heat transfer surfaces and induce turbulent flow, thereby improving cooling efficiency through increased heat dissipation, particularly in applications such as hydrogen fuel cells. Over the past decade, their use has become critical in various industrial systems. This study presents a numerical investigation of flow dynamics and heat transfer in rectangular mini-channels (RMC) and pin-fin heatsinks (PFHS), focusing on diamond-shaped pin-fins arranged in a segregated, corrugated configuration. To accurately determine the heat transfer coefficient within this complex thermal system, key parameters—including mass flow rate, geometric dimensions, heat flux, and reference temperature—are thoroughly analyzed. Special emphasis is placed on the method of calculating the reference temperature, as its precise estimation is crucial for optimizing cooling performance. The study introduces a novel technique to accurately determine the temperature difference between the cooling fluid and the heatsink wall, leading to an improved approach for estimating the heat transfer coefficient. A variable reference temperature (VRT) method is employed to calculate the wall-fluid temperature difference. Both qualitative and quantitative analyses are conducted to evaluate flow and heat transfer characteristics. The numerical methodology is validated through experimental measurements, demonstrating that the proposed reference temperature calculation method provides a more accurate representation of the heat transfer coefficient. Additionally, a new correlation is developed to describe the relationship between the averaged heat transfer coefficient and the Reynolds number. This work offers a refined approach to heat transfer coefficient estimation, contributing to the optimization of cooling processes in advanced thermal systems.