Transient Vapor Compression Refrigeration Cycle for Electronics Cooling - Part 1: Distributed Model Validation

For high-power electronic systems, such as high-concentration photovoltaics arrays, laser diode arrays, and high-density data centers, two-phase cooling technologies are being explored to significantly reduce heat convection resistance from electronics’ wall to the ambient. Lower electronics surface or junction temperatures lead to higher energy conversion or computation efficiency; therefore, thermal management is a critical issue for energy efficient electronic system operation. In large-scale electronics cooling systems, there usually exist many distributed and transient heat sources. The non-uniform heat loads could cause severe flow mal-distribution problems and local device burn-out (i,e, a difficult thermal management challenge). Vapor compression refrigeration cycles have been identified as promising solutions to ultra high-power electronics cooling. A well-designed active refrigeration cooling system is expected to achieve higher transient cooling capability and energy efficiency. This paper presents a comprehensive first-principle dynamic refrigeration cycle model to understand its fundamental mass, energy, and momentum transport mechanisms in transient operation. Experimental validation results show the proposed distributed vapor compression cycle model has excellent steady-state and transient prediction performance. The proposed distributed dynamic model is able to provide valuable design and operation guidelines for energy-efficient electronics cooling systems under transient and non-uniform heating scenarios.