Evaluation of the thermal performance of hybrid nanofluids in pulsating heat pipe

• Main Authors: Zufar, M., Gunnasegaran, P., Ng, K.C., Mehta, H.B.
• Format: Article
• Language: English
• Published: 2020
• Online Access: http://dspace.uniten.edu.my/jspui/handle/123456789/13225
• Institution: Universiti Tenaga Nasional

The present article performed experimental and numerical investigations to evaluate the thermal performance of hybrid nanofluids in PHP under heat input and filling ratio of 10 W – 100 W and 50 %-60 %, respectively. The thermal performance results of PHP incorporated with hybrid nanofluids were compared with water. Water has low thermal conductivity value which is not favourable for an efficient heat transfer in a cooling device. Several studies have shown that hybrid nanofluid as a promising working fluid for thermal performance enhancement of the heat transfer device. The present study uses Al2O3-CuO hybrid nanofluid and SiO2-CuO hybrid nanofluid with mass concentration of 0.1 %. The thermal performance of PHP was studied with respect to the start-up mechanism, steady-state evaporator temperature, thermal resistance and the formation of two-phase flow. From the experiment results, PHP filled with SiO2-CuO hybrid nanofluid obtained the lowest thermal resistance value of 0.27 °C/W. Thermal resistance was improved by 55 % when PHP was charged with SiO2-CuO hybrid nanofluid compared to water. The optimal filling ratio of PHP is found to be 60 % at all the heat input and working fluid tested. Incorporating hybrid nanofluids in PHP have seen to expedite the start-up mechanism and also showed lower steady-state evaporator temperature and thermal resistance values. © 2019 PENERBIT AKADEMIA BARU-All rights reserved.