Investigation of thermal performance of modified vertical rectangular fin array in free convection using experimental and numerical method Anilkumar Sathe a,⇑ , Sudarshan Sanap a , Sunil Dingare a , Narayan Sane b a MIT School of Engineering, Pune 412201, India b Walchand College of Engineering, Sangli 416415, Maharashtra, India article info Article history: Received 25 March 2020 Received in revised form 27 May 2020 Accepted 18 June 2020 Available online xxxx Keywords: Thermal performance Natural convection Rectangular fin with slits Heat sink Flow pattern Heat transfer augmentation abstract Heat transfer by free convection from fin array is influenced by modification in size and shape of the fins as well as interruption in fluid flow. The objective of heat sink is the thermal management of electronic devices by removing excessive heat and improve the lifespan of the device. The paper investigates the thermal performance of free convection heat transfer with vertical heat sink by providing slits along the vertical surface of the fins. For the evaluation purpose two different arrangements viz. plain fin and slitted fin are selected. Fins are made from high thermal conductivity aluminium material and five dissimilar heat inputs are selected for study. The experimental and numerical findings are confirmed using the theoretical correlations available from the literature. The effect of number of slits and width of slits is investigated on convective heat transfer coefficient. Numerical study is used to understand the flow patterns around the vertical fin surface. It has been observed that the presence of slits on the surface appreciably improves the thermal performance of ver- tical fin array. Ó 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by- nc-nd/4.0) Selection and Peer-review under responsibility of the scientific committee of the International Conference & Exposition on Mechanical, Material and Manufacturing Technology. 1. Introduction The heat sinks are popularly used for cooling electrical, elec- tronics and automotive parts in various industrial applications. They are useful at elevated temperatures in extracting heat from the surfaces. The survival of such instruments depends on the tem- perature of their operation. Heat sinks are important components of most of these devices’ thermal management systems. In certain cases, where heat transfer is through natural convec- tion where the value of heat transfer coefficient is less, because of low cost and maintenance free operation fins are the suitable choice. The most critical construction criteria are the weight and scale of the equipment. In the present situation, the compact sys- tem plays very important role which reduces overall size of the equipment. With rise in temperature the failure rate of electrical devices increases exponentially. Even significant sources of failure are the high thermal stresses in the solder joints of electronic devices placed on circuit boards arising from temperature fluctua- tions. Hence thermal control has been a key element in electronic equipment manufacturing and functioning. The purpose of the proposed study is to analyse numerically and experimentally the thermal efficiency of the vertical rectangu- lar plate-fin system with slits in free convection mode. The results will be compared with the case of regular plate fin array without slits. 2. Literature survey In the past, many researchers worked on improving thermal performance of heat sink composing of fin array with different ori- entation and geometry. Shyy-Woei Chang et al. [1] investigated numerically the influ- ence of dimples using three-dimensional steady-state and heat transfer in free convection mode for a collection of vertical fine arrays. For obtaining the data about temperature, velocity and Nus- selt number, momentum and energy equations were solved. For solving these equations finite volume method and SIMPLE algo- https://doi.org/10.1016/j.matpr.2020.06.389 2214-7853/Ó 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Selection and Peer-review under responsibility of the scientific committee of the International Conference & Exposition on Mechanical, Material and Manufacturing Technology. ⇑ Corresponding author. E-mail address: anilkumar.sathe@mituniversity.edu.in (A. Sathe). Materials Today: Proceedings xxx (xxxx) xxx Contents lists available at ScienceDirect Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr Please cite this article as: A. Sathe, S. Sanap, S. Dingare et al., Investigation of thermal performance of modified vertical rectangular fin array in free con- vection using experimental and numerical method, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2020.06.389