The Viscous Dissipation Effect in a Regular Polygonal Duct for H2 Boundary Conditions

A numerical investigation based on the Boundary Element Method (BEM) was carried out to solve laminar forced convection with viscous dissipation in a straight regular polygonal duct with H2 boundary conditions. The axial heat conduction in the fluid is neglected. The effects of the Brinkman number and Nusselt number for both the wall heating case and the wall cooling case are considered. Nusselt numbers are obtained as a function of the number of sides of a regular polygonal duct and of the Brinkman number. The singular points of the Brinkman number and the Brinkman number for a limited Nusselt number when the total heat flux reached the heat flux that is generated internally by viscous dissipation processes are obtained. (paper)