03.2020.213.223

DEVELOPMENT OF NATURAL CONVECTION HEAT TRANSFER IN HEAT SINK USING A NEW FIN DESIGN

Author(s):
Hisham H. Jasim*

Affiliation(s):
Mechatronics Engineering Department, AL-Khwarizmi College of Engineering, University of Baghdad, Iraq.

*Corresponding Author Email: hisham@kecbu.uobaghdad.edu.iq

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Improve of heat sink performance suffers from diverse levels of difficulties due to the complexities of the work environments. For that, researchers try always to develop the performance of heat sink using many ways. Therefore, the enhancement of heat sink performance by using the combination between two types of fin was investigated in this study. All models have constant parameters (size and weight) of heat sink to test the level of enhancing achieved, compared with the original model (longitudinal-fin). Converting part of the original size into pin fins, led to the emergence of a hybrid design (longitudinal – pins fin) that was studied numerically using Finite Element Method and validated by computational simulation (Ansys). The results were conducted for natural convection and Ra=107. While, range of surface area was expanded from 1 to 1.8 times. The strong agreement of the validation results (0.31% – 0.52%) showed the reliability of the presented model. Furthermore, the results demonstrated that the hybrid designs have discrimination in several aspects. Consequently, reduced of fin temperatures by (2.7% to 8.8%), lower thermal resistance by (24% to 46%), and augmentation of heat transferred by (31% -80%), compared with longitudinal fin. Meanwhile, entropy generation was minimized with an increase in area ratio for constant heat flux according to the decrease of thermal resistance. Improvement of thermal parameters does not behave in the same approach due to the an overlapping between the effects of miscellaneous parameters, especially at an area ratio greater than 1.5. This led to the approximate steady state of entropy generation starting from the optimum point at area ratio 1.5.