Condensation of laminar film over curved vertical walls using single and two-phase nanofluid models

Recently, an analytical solution was derived for the governing equations of condensate laminar film from stationary vapors on curved vertical walls of convex/concave shape (Soliman et al., 2014). The present research paper develops a theory covering the impacts of different nanofluids and derives further closed form solutions concerning the hydrodynamic and thermal transport through the condensate film over curved walls when the single phase and two-phase models of nanofluids are taken into account. From both approaches, exact expressions are obtained for the velocity and, temperature fields as well as the shear stress, thickness and Nusselt number of the film influenced by the presence of nanoparticles of frequently used nanofluids in the literature. It is found that heat transfer is enhanced, even more in the two-phase model case in the presence of nanoparticles. The concentration of Ag nanoparticles favors the best rate of heat transfer among the considered nanofluids. (C) 2017 Elsevier Masson SAS. All rights reserved.