Turbulent film condensation on a non-isothermal horizontal tube-effect of eddy diffusivity

A theoretical study is made into the process of heat transfer with vapor condensation on a non-isothermal horizontal tube submerged in a forced vapor flow. The interfacial eddy diffusivity effect included in the energy relation is first considered here. The interfacial shear at the vapor condensate film is evaluated by employing the Colburn analogy. The condensate film flow and condensing heat transfer characteristics from a non-isothermal horizontal tube under the effects of the non-uniform wall temperature variation, the Froude number, sub-cooling parameter and system pressure parameter have been investigated. As the wall temperature variation amplitude increases, the value of the dimensionless mean heat transfer result, Nu¯Re-1/2, with the inclusion of the eddy diffusivity effect, decreases insignificantly.