National Science Foundation
Cooling Technologies Research Center
Purdue University - School of Mechanical Engineering logo

CTRC Breakthroughs

Small Scale Refrigeration

Liquid Loop brekathroughs figure When choosing the coolant for a specific application, the material compatibility, toxicity, corrosion properties have to be considered in addition to their thermal performance.  This project focused on answering these system considerations. As a part of the project, an extensive liquid-loop coolant database was developed with 56 single-phase and two-phase fluids that can be used in electronics cooling.  In addition, a simulation tool was developed to predict the coolant performance in single-phase and two-phase flow microchannels.

Miniature Scale Linear Compressor for Electronics Cooling

Linear Compressors breakthroughs figure A linear compressor is considered a promising new development in component technology due to the potential for high performance and high scalability. This work has developed a comprehensive model of a linear compressor based on first principals. This model has shown good agreement when compared with experimental data and can be used for future development of linear compressor technology. The figure is a schematic of a linear compressor.

Miniature-Scale Refrigeration System (MSRS) for Electronics Cooling

MSRS breakthroughs figureThe simulation model for the refrigeration system is based on thermodynamics, heat transfer and fluid mechanics concepts applied to miniature scale components of a micro vapor compression system, including the compressor, mini-channel condenser, expansion device, and integrated cold plate evaporator and heat spreader. The system model shown in the figure simulates a refrigeration system with an active expansion device. Hence, only two parameters, suction and discharge pressures, need to be estimated to completely define the operating conditions and performance of the vapor compression system. The model predicts all state points of the micro-refrigeration system and the power consumption and the efficiency of the cooling system.

Miniature-Scale Daiphragm Compressor for Electronics Cooling

MSDC breakthroughs figureResults from the compressor model indicate that an Miniature Scale Diaphragm Compressor (MSDC) has excellent thermodynamic performance and good potential for miniaturization and integration with micro-refrigeration systems to cool high-heat-dissipation microprocessors. The diaphragm compressor consists mainly of two contoured conductive planes that serve as electrodes. These are separated by dielectric insulation layers and a gas/refrigerant gap. If a voltage differential is applied between the electrodes, the electrostatic force deforms the diaphragm and pulls it towards the electrode on the chamber wall. Suction and discharge flapper mini-valves control the refrigerant flow in and out of the compressor chamber. Target parameters for the diaphragm compressor include a heat removal of 200 W, pressure head of 750 kPa, pressure ratio of 2, and flow rate of 3000 ml/min, accomplished with a diaphragm compressor of 80 mm in diameter and 20 mm in height.