EXPERIMENTAL INVESTIGATION OF HOT-SIDE THERMAL MANAGEMENT AND OPERATING-POINT OPTIMIZATION FOR A COMPACT THERMOELECTRIC WATER-COOLING SYSTEM

Abstract

Refrigerant-free cooling technologies are more appealing for point-of-use water dispensing, portable electronics, and small-scale applications in the medical field. However, the coefficient of performance (COP) of thermoelectric coolers (TECs) is comparatively low and heat is accumulated at its hot side. This study experimentally explores the hot-side thermal management and operating-point control of a compact thermoelectric water-cooling prototype that utilizes two TEC1-12706 Peltier modules working in parallel with dedicated forced convection heat sinks and axial fans. The prototype was tested to see how well it worked by cooling 1 liter of water from 25 °C to 15 °C in ambient temperature of 30 °C and recording various thermal and electrical parameters. The experimental results showed that the cooling time was found to be 26 min which is significantly higher than the idealized theoretical cooling time, mainly because of the environmental heat gain, non-steady-state cooling property, and progressive increase in the temperature of the hot side. The analysis showed that the instantaneous COP values are significantly different from the time-average COP, indicating that the performance evaluation method of thermoelectric cooling research should be standardized and transparent. Overall, the results show that a significant degree of hot-side thermal management is necessary, but not sufficient to attain high system efficiency. The study offers a practical and repeatable operating model for designing and testing low cost and compact thermoelectric water-cooling systems.