Forced Convection through Discrete Heat Sources and Simple Thermal Model – A Numerical Study

Kartikaswami Hasavimath,Kishan Naik,Banjara Kotresha,N Gnanasekaran

doi:10.33889/ijmems.2019.4.6-110

Kartikaswami Hasavimath, Kishan Naik + Show 2 more

Open Access

https://doi.org/10.33889/ijmems.2019.4.6-110

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Abstract

In this work a forced convection through discrete heat sources and simple thermal model placed inside the vertical channel is analyzed numerically. The problem considered for the investigation comprises of a vertical channel with distinct heat source assembly located at the center of the channel. The novelty of the present work is to replace the discrete heat source assembly by a simple thermal model to obtain uniformly distributed temperature and streamlines. A conjugate heat transfer investigation is carried out because the problem domain consists of aluminum solid strips as well as Bakelite strips in discrete heat source assembly which are replaced by a aluminum solid in case of simple thermal model. The numerically obtained data are initially compared with experimental data for the purpose of validation. The temperature of each discrete sources decrease with increase in inlet velocity of the fluid and bottom heat source is able to take higher heat load. The results in terms excess temperature obtained for both discrete heat source and simple thermal model is presented and discussed.

Highlights

IntroductionThe rapid development of electronic industries and reduced dimension of electronic components results in less space for excessive heat dissipation
A boundary layer mesh is used near the wall and near the discrete heat sources as well as near the simple thermal model
The excess temperature in the channel is less in the case of simple thermal model compared to discrete heat source

Summary

Introduction

The rapid development of electronic industries and reduced dimension of electronic components results in less space for excessive heat dissipation. Premachandran and Balaji (2006) numerically investigated heat transfer through extended heat sources in a channel by keeping the size of channel, thickness of heat sources and spacing between the heaters as constant They found that maximum temperature and effect of radiation decreases as Reynolds number increases. Chen et al (2013) performed analysis of forced convection in metal foams placed in a horizontal channel with distinct heaters placed on the bottom wall of the channel They found that the increasing the heat exchange between solid and fluid phases at the interface results in reduction in the excess temperature between the solid and fluid phases at a particular velocity. Kotresha and Gnanasekaran (2019) numerically calculated the forced convection through discrete heat sources attached with metallic foams in a vertical channel They considered two dissimilar types of metal foam material for the investigation. The net heat input to the heater for simple thermal model is given in Eq (6)

Grid Independence Study

Validation of Numerical Results

Thermal Results Figure 4 and