Prediction of transpiration effects on heat and mass transfer by different turbulence models

Abstract The paper reports the results of a study related to transpirating flows, stimulated by the interest that these phenomena, occurring in the presence of simultaneous heat and mass transfer, have for nuclear reactor applications. The work includes a summary and the follow-up of previous experimental and numerical investigations on filmwise condensation and falling film evaporation and of a recent review of different forms of the heat and mass transfer analogy. The particular objective here pursued is to compare transpiration effects as predicted by different turbulence models with classical suction and blowing multipliers based on stagnant layer theories, in the attempt to clarify their quantitative implications on the predicted mass transfer rates. A commercial and an in-house CFD code have been adopted for evaluating the heat and mass transfer rates occurring over a flat plate exposed to an air-vapour stream, with uniform bulk steam mass fraction and temperature boundary conditions at the wall. This simple configuration was purposely selected since it is a simplified representation of the test section of an experimental facility presently in operation at the University of Pisa. This allows a direct comparison between the heat and mass transfer coefficients predicted by CFD models and classical correlations for Nusselt and Sherwood numbers.

[1]  J. Thome,et al.  Convective Boiling and Condensation , 1972 .

[2]  G. Yadigaroglu,et al.  Scaling of Containment Experiments , 2003 .

[3]  Nicola Forgione,et al.  On Various Forms of the Heat and Mass Transfer Analogy: Discussion and Application to Condensation Experiments , 2006 .

[4]  W. Jones,et al.  The prediction of laminarization with a two-equation model of turbulence , 1972 .

[5]  L. C. Chow,et al.  Evaporation of water into a laminar stream of air and superheated steam , 1983 .

[6]  T. Shih,et al.  New time scale based k-epsilon model for near-wall turbulence , 1993 .

[7]  Per F. Peterson,et al.  Diffusion Layer Theory for Turbulent Vapor Condensation With Noncondensable Gases , 1993 .

[8]  D. Spalding A standard formulation of the steady convective mass transfer problem , 1960 .

[9]  Ken-ichi Abe,et al.  A new turbulence model for predicting fluid flow and heat transfer in separating and reattaching flows—I. Flow field calculations , 1995 .

[10]  D. Mazzini,et al.  Computational Study of Evaporative Film Cooling in a Vertical Rectangular Channel , 2002 .

[11]  W. Ambrosini,et al.  Experiments and CFD Analyses on Condensation Heat Transfer in a Square Cross Section Channel , 2005 .

[12]  Nicola Forgione,et al.  Discussion of Heat and Mass Transfer Models on the Basis of Experiments and CFD Calculations , 2005 .

[13]  B. Launder,et al.  Application of the energy-dissipation model of turbulence to the calculation of flow near a spinning disc , 1974 .

[14]  K. Chien,et al.  Predictions of Channel and Boundary-Layer Flows with a Low-Reynolds-Number Turbulence Model , 1982 .

[15]  J. P. V. Doormaal,et al.  ENHANCEMENTS OF THE SIMPLE METHOD FOR PREDICTING INCOMPRESSIBLE FLUID FLOWS , 1984 .

[16]  Geoffrey F. Hewitt,et al.  Two-Phase Flow and Heat Transfer , 2019, Fundamentals of Multiphase Heat Transfer and Flow.

[17]  J. Lienhard A heat transfer textbook , 1981 .

[18]  Frank P. Incropera,et al.  Fundamentals of Heat and Mass Transfer , 1981 .

[19]  R. M. C. So,et al.  A critical evaluation of near-wall two-equation models against direct numerical simulation data , 1997 .

[20]  Nicola Forgione,et al.  Experimental Investigation and Modelling of Film Evaporation in the Presence of Countercurrent Air Flow , 2000 .

[21]  K.-Y. Chien,et al.  Predictions of channel and boundary-layer flows with a low-Reynolds-number two-equation model of turbulence , 1980 .