HEAT TRANSFER OF LAMINAR FLOW IN VERTICAL TUBES WITH CONSTANT WALL HEAT FLUX

Abstract

Theoretical and experimental studies were performed on heat transfer to fluids with variable physical properties, fully developed laminar flow in vertical tubes, under the condition of constant wall heat flux.
In the course of analysis the temperature dependence of viscosity and density was taken into account.
The final results were envisioned as the relation between local Nusselt number and local Graetz number, having ε and Gr₀/64Re₀ as parameters.
Experimental data were obtained in the above system with water or aqueous solutions of cane sugar, and the analytical solutions are in a fairly good agreement with the above experimental data.