Modifications of the turbulent diffusion layer model for the condensation heat transfer under the presence of noncondensable gases

摘要

The condensation heat transfer model of the MARS-KS1.5 code tends to under-predict the condensation in the presence of noncondensable gases. In our previous study, we adopted the diffusion layer model and modified it in order to consider the effect on turbulence on diffusive mass transfer in the diffusion layer. In this work, further modifications were made by introducing the boundary layer theory for natural convection flow.The new condensation model has been validated against 442 experimental data collected from eight different facilities. It is shown that the results of the new model for natural convection flow are more accurate result than those of the previous model. It is confirmed that the new model works well for the condensation in forced convection flow. The relative root mean square error of the new model is reduced to 0.193 from 0.242 of the previous model and 0.401 of the original one. (C) 2019 Elsevier Ltd. All rights reserved.