Natural convection heat transfer from isothermal horizontal rectangular ducts

Abstract

Laminar natural convection heat transfer from horizontal rectangular cross section cylinder in air is investigated numerically. Different aspect ratios are examined under laminar conditions. The computational procedure is based on the finite element technique. Results are presented in the form of streamlines, temperature, velocity and heat flux plots around the circumference of the ducts. Heat transfer data are generated and presented in terms of mean Nusselt number versus Rayleigh number for different aspect ratios. Correlation covering the used aspect ratios is obtained in dimensionless form of Nusselt number, Rayleigh number and aspect ratio.