Thermal Management and Layout Optimization of LED Downlights Using CFD Simulation and Experimental Analysis

Abstract

The increasing global demand for energy efficiency and environmental sustainability has positioned Light Emitting Diodes (LEDs) as a leading solid-state lighting (SSL) technology. LEDs offer numerous advantages, including high luminous efficacy, energy savings of up to 75% compared to traditional lighting, long service life and environmental friendliness. However, nearly 80–85% of LED input power is dissipated as heat, which significantly impacts their performance, reliability and lifetime if not managed effectively. This research focuses on the thermal management of LED downlights through Computational Fluid Dynamics (CFD) simulations and laboratory experiments. An 8-inch, 25W LED downlight is modeled using ANSYS APDL to analyze heat conduction, convection and radiation. Temperature distribution results from simulations are validated against experimental data, with less than 2% error in most cases, demonstrating the model’s reliability. Further, optimization studies are performed to determine the ideal LED quantity and ring distance for improved heat dissipation. Results reveal that a 48-LED configuration with optimized spacing provides superior thermal performance, lowering maximum operating temperature by ~10% and extending the downlight’s service life. The findings provide valuable insights for manufacturers to enhance LED product reliability through efficient thermal design and layout optimization, balancing energy efficiency, performance and longevity.