Numerical Simulations of Coupled Conduction-Free Convection in Low Conductive Vertical Finned Surfaces

Numerical Simulations of Coupled Conduction-Free Convection in Low Conductive Vertical Finned Surfaces

Alessandra De Angelis Michele Libralato Onorio Saro 

Università di Udine, DPIA, via delle Scienze 206, Udine 33100, Italy

Corresponding Author Email: 
onorio.saro@uniud.it
Page: 
98-102
|
DOI: 
https://doi.org/10.18280/mmc_c.790306
Received: 
24 March 2018
| |
Accepted: 
28 May 2018
| | Citation

OPEN ACCESS

Abstract: 

Several industrial products and applications need to remove a large amount of thermal energy that arises from very small surfaces; typical solutions to this problem are heat sinks, dissipating heat devices in electrical and electronic appliances. In most cases they are cooled by means of finned surfaces and forced air. In some cases, especially in low-energy applications, free convection solutions could be preferable to forced convection ones. Usually, heat sinks are made of expensive aluminium or copper due to their high thermal conductivity. When the devices are small, and the solid-fluid temperature difference is limited, in free convection the heat transfer coefficient is typically low, and the thermal conductivity of the materials is less relevant. A less expensive possibility is the use of different materials that, despite their low thermal conductivity, can allow an easier production process as in the case of quasi-polymeric materials. In this paper, the free convection problem of small vertical finned surfaces immersed in still air has been investigated by means of numerical simulations in order to identify the influence of geometrical and physical parameters on the system performance with a moderately conductive polymeric material and a low-density Zn-based alloy.

Keywords: 

free convection, finned surface, numerical simulation, low thermal conductivity

1. Introduction
2. Simulations
3. Simulations
4. Conclusions
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