Improvement of natural convection heat dissipation of a conventional pin-fin heat sink by applying a helical wire spring

Abstract

Effective heat dissipation of electronic devices including high-power light-emitting diodes (LEDs) is essential in applications requiring both compact size and high performance. In such environments, passive cooling technologies providing high heat dissipation with simple structures are particularly desirable. This study proposes a new method to enhance the cooling performance of conventional pin-fin heat sinks by applying a spring-shaped wire structure around the outer surfaces of the fins. Aluminum 6061 or SAC305 wire was formed into a helical spring and wrapped around the fins without altering the original heat sink geometry, enabling attachment to existing products. The spring structure increases the effective surface area and guides airflow between fins, thereby enhancing free convection heat transfer. Experiments and numerical simulations were conducted to evaluate the thermal performance of the proposed design. For the reference heat sink without springs, a simple rising buoyant flow developed between the fins. In contrast, the spring-equipped heat sink induced more complex flow paths along the spring geometry, promoting enhanced air circulation. This resulted in more uniform heat distribution and a reduction in overall thermal resistance. Comparative analysis under different installation angles showed that the aluminum-spring-applied heat sink achieved a maximum thermal-resistance reduction of 11.72% relative to the reference model, demonstrating consistent performance improvement under various orientations. These results show that the simple addition of a spring structure can significantly improve the natural-convection cooling performance of conventional heat sinks, indicating its potential as a scalable and feasible thermal management solution for high-power electronic devices and LED lighting systems.