Development of heat and mass transfer model for condensation

Divergence and the interfacial temperature deviation are the two main problems in condensation simulation with the Lee model. Based on the heat transfer analysis at the vapor-liquid interface, a correlation is revealed describing the relationship between interfacial temperature deviation and the model parameters, qi ≈ (Tsat − Ti)(Akv)0.5 where A = hfgrρv / Tsat. With this correlation, the determination of the condensation frequency r is no longer empirical. Furthermore, the correlation indicates that the thermal conductivity of vapor plays an important role. Accordingly, an improved model is proposed amplifying the thermal conductivity of vapor in the phase interaction region. The model is verified with the Nusselt problem and the impacts of the model parameters are discussed and compared with the original Lee model. It is shown that the interfacial temperature deviation is reduced by the amplified thermal conductivity of vapor. The convergence is maintained by increasing both A and kv synchronously. Verification is also obtained on the forced convection condensation of R134a. The correlation predicts a temperature deviation at 0.1 K and the numerical result successfully reaches 0.12 K.