Question: Consider fully developed laminar flow with constant properties in a circular tube. Let there be heat transfer to or from the fluid at a constant rate per unit of tube length. Additionally, let there be heat generation within the fluid (perhaps by nuclear reaction) at a rate S, W/m", that is everywhere the same. Determine an expression for the Nusselt number as a function of the pertinent parameters. (What are they?) Evaluate the convection conductance in the usual manner, based on heat flux through the surface, surface temperature, and fluid mixed mean temperature.