Mixed convection film condensation from downward flowing vapors onto a sphere with uniform wall heat flux

Abstract

A model is developed for the study of mixed convection film condensation from downward flowing vapors onto a sphere with uniform wall heat flux. The model combined natural convection dominated and forced convection dominated film condensation, including effects of pressure gradient and interfacial vapor shear drag has been investigated and solved numerically. The separation angle of the condensate film layer, φs is also obtained for various pressure gradient parameters, P* and their corresponding dimensionless Grashof 's parameters, Gr*. Besides, the effect of P* on the dimensionless mean heat transfer, \(\) will remain almost uniform with increasing P* until \(\) for various corresponding available values of Gr*. Meanwhile, the dimensionless mean heat transfer, \(\) is increasing significantly with Gr* for its corresponding available values of P*. For pure natural-convection film condensation, \(\) is obtained.