A novel technique to enhance thermal performance of a thermoelectric cooler using phase-change materials S. Manikandan 1 • C. Selvam 1 • P. Pavan Sai Praful 1 • Ravita Lamba 2 • S. C. Kaushik 2 • Dongliang Zhao 3 • Ronggui Yang 3 Received: 22 March 2019 / Accepted: 29 April 2019 Ó Akade ´miai Kiado ´, Budapest, Hungary 2019 Abstract In the present work, a novel technique has been developed to enhance the thermal performance of a thermoelectric cooler (TEC) by integrating with phase-change material (PCM). The PCM has been integrated at the hot side of the thermoelectric cooler to maintain constant and relatively low temperature. The study has been carried out with variable geometric parameters of the heat sink, variable cooling load conditions, variable input currents to the TEC and with different PCMs. The results show that there is a significant reduction in both hot and cold side temperatures of the thermoelectric cooler with the use of PCM. For a typical operating condition in the TEC with two thermocouples (2 mm 9 2 mm 9 3 mm each) under cooling load of 0.03 W and convective heat transfer coefficient of 5 Wm -2 K -1 , the hot and cold side temperatures of the TEC have been reduced from 52 to 30 °C and 25 to 12 °C, respectively, with the use of PCM. The coefficient of performance of the TEC integrated with PCM has been estimated and it has been found to be 30% higher than the TEC without PCM for a cooling load of 0.05 W. Moreover, the thermal performance of TEC has been studied with variable fill volume of PCM in the heat sink. It has been found that the increase in fill volume of PCM increases the thermal performance of the TEC. This study has been carried out with different PCMs and similar performance enhancements have been observed. Keywords Thermoelectric cooler Á Phase-change materials Á Heat sink List of symbols h Heat transfer coefficient/Wm -2 K -1 A Area/m 2 H Height/mm I Current/A L Latent heat of fusion/kJ kg -1 N Number Q Heat/W T Temperature/ o C W Width/mm Z Figure of merit/K -1 Subscript a Environment c Cold side of TEC fin Fins h Hot side of TEC m Mean n n-type material p p-type material Greek Letters D Difference Introduction The threat to the environment caused by the refrigerants used in conventional refrigeration and air-conditioning systems is increasing day by day. To overcome this issue, alternative cooling techniques, which does not use any hazardous refrigerant or produce cooling without using any refrigerant should be explored. One such technique is the & Dongliang Zhao dongliang.zhao@colorado.edu 1 Department of Mechanical Engineering, SRM Institute of Science and Technology, Kattankulathur, Chennai, India 2 Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi, India 3 Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, CO 80309, USA 123 Journal of Thermal Analysis and Calorimetry https://doi.org/10.1007/s10973-019-08353-y