Absorption refrigeration method with alternative water-ammonia solution circulation system for microelectronics cooling

The study develops an analytical model of an optimized small scale absorption ammonia/water refrigeration system, designed to fit smaller scale power electronics, using a pump to circulate the binary ammonia-water solution cooling agent in the proposed miniaturized system. This continues the authors´ previous study of a refrigeration absorption system, by replacing the thermo-siphon and gravitational based circulation of the compensatory hydrogen gas with an actual circulation mini-pump, with application to the cooling of the electronic components populating a Printed Circuit Board (PCB) in a High-Power Microelectronics System. It is a viable alternative to the simple absorption system, due to the increase in COP from 0.4 to 0.7, while providing improved feasibility and reliability at smaller scales. The proposed system includes miniaturized refrigeration components, compact heat exchangers with meso-channels and circulation mini-pump working in a multi-step optimization (regenerative) cycle to improve the overall efficiency of the absorption system and increase the COP to 0.7. The system with pump will be simplified without the need of additional systems to provide the thermo-siphoning functionality presented in the previous study. The efficiency of the system is evaluated and compared to mechanical compression designs at similar cooling powers, and discusses the thermodynamic cycle specifics and provides an extensive analytical evaluation and calculation of each miniaturized component design. The study is concluded by identifying the pros and cons of implementing such an absorption system to real-life microelectronics applications.