화학공학소재연구정보센터
Chemical Engineering Science, Vol.191, 436-447, 2018
Influence of chevron fin interruption on thermo-fluidic transport characteristics of nanofluid-cooled electronic heat sink
In the current study, the effects of different interruptions of fin on the transport characteristics of a nanofluid-cooled electronic heat sink with chevron shape are analyzed numerically. Seven interruptions of fin are explored and compared with the integral case. Water and water-based nanofluid with Al2O3 nanoparticle at volume fractions of 0.5% and 1.0% are tested as the coolant in laminar flow regime (Reynolds number less than 900). All coolants are also tested experimentally in the heat sink equipped with the integral fin, and the achieved data are used to verify the numerical approach. The obtained results disclose that the use of interrupted fins leads to a superior heat transfer process due to a decrease in the fin surface temperature and a rise in the outlet coolant temperature. Simultaneously, it causes considerable decrements in the pressure drop which is because of an increase in the fin porosity of the heat sink. The percentage variation in heat transfer coefficient for the interrupted fins as compared with the integral case is in the range of -9.3% to +43.6% while the percentage variation in the pressure drop is in the range of -43.5% to -92.7%. Among all interrupted models, the one reaching the performance index of 3.09 at the Reynolds number of 300 is the best. Furthermore, the water-based nanofluid shows a better thermal performance and a certain penalty in the pressure drop compared to water. The water-based nanofluid can enhance the performance index of the heat sink by an average of 14.7% and 28.3%, which correspond to 0.5% and 1.0% volume fractions of Al2O3 nanoparticle, respectively. Finally, it can be concluded that the compound technique used for the chevron fin (interruption + nanofluid) can be a good choice in practical applications to improve the overall performance of electronic heat sinks. (C) 2018 Elsevier Ltd. All rights reserved.