TWO- AND THREE-DIMENSIONAL TRANSIENT ANALYSIS OF FLOW AND HEAT TRANSFER IN STRUCTURES WITH DOMICAL AND CURVED ROOFS

Year 2017, Volume: 3 Issue: 5, 1489 - 1497, 19.09.2017

Zekeriya Altaç

https://doi.org/10.18186/journal-of-thermal-engineering.338895

Cited By: 1

Abstract

The aim of this study is to investigate transient
buoyancy driven free convection heat transfer in domical (with a dome)
structures or curved roofs is numerically. Two- and three-dimensional turbulent free
convection are considered for the Rayleigh number intervals (10⁸≤Ra≤10¹⁰). The aspect ratios
of H/L=1 and 2, with respect to the
heated length, are considered. The heating is provided from a lateral surface
while cooling is from opposing lateral surface. The hot and cold surfaces are
kept isothermal, and all other surfaces are adiabatic. The Boussineq
approximation is used for modeling the buoyancy flow. The RNG k-e turbulence model is used. The pertinent
transient equations are solved using Fluent 6.3.26 software. The flow of air
(streamlines) and temperature distribution (isotherms) are produced. The mean
Nusselt number is evaluated over the isothermal hot wall is computed, and the
results are analyzed with respect to the flow and geometric variations.  The mean Nusselt number using the 2-D
simulations indicate that the mean Nusselt number does not significantly change
with H/L ratio. The 3-D simulations
yield higher mean Nusselt numbers, but they are smaller than those of obtained
for flat top enclosures.

Keywords

Buoyancy Flow, Domical Structure, Natural Convection, Turbulent Heat Transfer

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