In this investigation of the two-phase, annular-mist flow of a condensing vapor, the following significant conclusions are drawn. The conclusions are based on the numerical results obtained from the theoretical analysis. Where appropriate, recommendations for future studies are included: 1. The analytical model accurately predicts the condenser length necessary for complete condensation and, with a reasonable degree of accuracy, the dynamic quality, heat transfer characteristics, and static pressure distribution. 2. An integral analysis is presented for which the assumed velocity and enthalpy profiles are the power-law type. For the range of temperatures and pressures encountered in this investigation, varying the profile shapes has a negligible effect on the dynamic quality and static pressure distributions at all except high vapor velocities. 3. The analysis accounts for the slip between the entrained particles and the vapor in the gas core. A constant entrainment slip ratio (SE) is assumed. Reducing the ratio below unity has an effect of the static pressure drop. The effect, however, is comparatively small. 4. Due to the lack of entrainment flow rate data available for two-phase, annular-mist, condensing flows, a variable entrainment correlation is included in the analysis. / Ph. D.