An analytical investigation of evaporation of laminar falling liquid film along an inclined wall is presented in this paper. The results for temperature distribution, local heat and mass Nusselt numbers and mass flow ratio are found to depend mainly on α, Pr and Ao. The other physical parameters igg, β and K are found to have only a mild effect on the results. © 1975 Springer-Verlag.

N. S.N. Murty

V. M.K. Sastri

HEAT EXCHANGERS - CONDENSERS

Heat transfer

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Evaporation of laminar falling liquid film along an inclined wall

Wärme- und Stoffübertragung

A finite-volume-based incompressible flow algorithm on Cartesian grid is presented for the simulation of evaporation phenomena in a falling liquid film under low wall superheat conditions. The model employs the PLIC-VOF method to capture the free surface evolution, and the continuum surface force (CSF) approximation to emulate the effects of interfacial tension. The phase change process is represented through a source term in the interfacial cells, which is evaluated from the normal temperature gradients on either side of the interface. In order to evaluate these discontinuous temperature gradients across the interface accurately, a simple and efficient ghost fluid method has been implemented, which properly takes into account the dynamic evolution of the interface. The overall numerical model, including the phase change algorithm, has been validated against standard benchmark analytical results. Finally, the model is used to simulate the evaporating flow of a 2-D laminar, developing film falling over an inclined plane surface, subjected to constant wall heat flux. The results thus obtained, clearly illustrate the significance of inertial effects in the developing region of the falling film, which are generally neglected in the available analytical models. It is also observed, that the evaporation of fluid commences only after the growing thermal boundary layer reaches the interface, and the length of the nonevaporating section reduces with the increase in wall heat flux value. Copyright © Taylor & Francis Group, LLC.

Journal	Data powered by TypesetWärme- und Stoffübertragung
Publisher	Data powered by TypesetSpringer-Verlag
ISSN	00429929
Open Access	No