LEDs' thermal management for special application

The aim of this work is related to the development of efficient, low-cost active LED cooling systems for industrial applications in horticulture, poultry housings, dairy farms and others. Investigations and comparative analysis of different variants of LEDs' cooling by use of different types of water pipes were carried out to find an optimum thermal performance. Two types of water pipes - polyethylene and PEX-AL-PEX were used in combination with different LEDs' heat sinks. In this study LEDs with power from 1 to 20 watts at different water flow rate through the active cooling were evaluated. Conventional measurements and infrared thermography are used for obtaining temperature distribution on LEDs' solder points, PCB, heat sinks and pipe surface. Safe modes for different operating regimes and different conditions are determined. Various proposals for use of waste heat have been made and thereby to improve the energy efficiency of lighting systems.