Heat Transfer Across a Turbulent Falling Film With Cocurrent Vapor Flow

Computational modeling of turbulent evaporating falling films

“…But eddy diffusivity profiles commonly utilized with internal or external flows single-phase flows [24,25] lack the ability to account for the dampening influence of surface tension on turbulence eddies near a liquid-vapor interface. Mills and Chung [26], Seban and Faghri [27], Hubbard et al [28], and Mudawar and El-Masri [29] recommended different formulations to account for the dampening of eddy diffusivity near the interface. Mudawar and El-Masri developed a single continuous eddy diffusivity profile incorporating the Van Driest model near the wall, an experimental profile derived from open channel flow data for the bulk region of the film, and a dampening multiplier for the interface region.…”

Prediction of heat transfer in turbulent falling liquid films with or without interfacial shear

“…Ishigai, Nakanisi, Heating Takehara, and Oyabu (1974) Spalding model for all y'+; Re agree with evaporation data of Chun and Seban (1971) Razavi and Damle (1978) cients in turbulent film heating, evaporation or condensation for both with or without interfacial shear. The turbulence model used in the present work incorporates the main features of the van Driest model used by Limberg (1973), Seban and Faghri (1976) and Hubbard et al (1976), but with two important differences. The first difference is the inclusion of the effect of interfacial shear through the variable shear stress term in the van Driest eddy viscosity model and the turbulent Prandtl number model.…”

“…Certain arbitrariness have been called upon in specifying the thickness of this region as have been done by Mills and Chung (1973), Hubbard et al (1976), and Seban and Faghri (1976). Until more information is gathered on understanding the nature of interface damping and predicting the thickness of this region, the specification of an eddy diffusivity as deduced from gas absorption data for the interface region of film heating, evaporation or condensation seems to be quite unjustified and unnecessary.…”

Heating and evaporation of turbulent falling liquid films

“…The evaporation or condensation problem addressed in this research has been studied theoretically by Seban (1 954), Dukler (1960), Lee (1964), Kunz and Yerazunis (1969), Mills and Chung (1973), Seban and Faghri (1976). Hubbard et al (1976), Mostofizadeh and Stephan (198 l), Kutateladze (1982), and Sandall et al (1 984). Heating or cooling of a turbulent liquid film has been studied by Limberg (1973) and Carey (1985).…”

“…In this note an analysis is carried out in which we somewhat modify the eddy diffusivity that was used to derive our prior results (Sandall et al, 1984). Here we use the eddy diffusivity for the interface region from Hubbard et al, (1976). The eddy diffusivity in the wall region is taken to be the same as was used to derive our prior results except that the Limberg (1973) reduction factor is applied, as recommended by Seban and Faghri (1976).…”