Visualization of Non-Equilibrium Two-Phase Flow

摘要

Recently, a few researchers have reported the presence of two-phase flow under subcooled conditions at theinlet of the capillary tube. In the present study, the effects of ambient temperature and R600a charge amounton the non-equilibrium two-phase state were investigated. The visualization results for most of the experimentsdemonstrated the presence of a non-equilibrium state at the inlet of capillary tubes of a refrigerator-freezer.The measured mass flow rates were compared with values predicted by Rasti et al. and Wolf and Pate empiricalcorrelations to investigate accuracy of empirical correlations under the non-equilibrium state. Both correlationscould predict the mass flow rate with large deviations under a non-equilibrium state. Finally, a new empiricalcorrelation was introduced to calculate the equivalent thermodynamic quality under the non-equilibrium state.The modified version of Rasti et al.’s correlation showed that 78.3% of data under the non-equilibrium statefell within relative deviations of ±25%.