Abstract
Laminar natural convection heat transfer from uniformly heated horizontal cylinders of a triangular cross-section is investigated numerically in air. Different cylinder cross-section dimensions and orientations are examined under laminar conditions. The computational procedure is based on the finite volume technique (using the commercial software FLOWORKS). Results are presented in the form of streamline and temperature contour plots around the perimeter of the cylinders. Some representations of thermal layers around the side of the cylinders are obtained for different modified Rayleigh numbers. General correlations of Nusselt numbers verse the modified Rayleigh numbers are obtained. Symmetric, transition, and asymmetric plumes are obtained and characterized for both positions of the cylinders.