Numerical Study of Boundary-Layer Transition in Flowing Film Evaporation on Horizontal Elliptical Cylinder

摘要: ABSTRACT A numerical study of the onset transverse and longitudinal transitions between turbulent laminar regimes during evaporation a water film is presented. The streams, without interfacial shear stress, along horizontal elliptical tube under simultaneous effects gravity, pressure gradients, viscous forces. Outside boundary layer, vapor-phase velocity obtained from potential flow. In analysis, turbulence model taking into account various gradients proposed, inertia convection terms are retained. Transfer equations discretized by using implicit Keller method. different models main parameters, such as initial liquid flow rate per unit length, Froude number, temperature difference wall liquid–vapor interface, ellipticity, on transition position evaluated. criterion given in term critical Reynolds number.