이산화탄소용 핀-관 증발기의 성능해석

Abstract

Fin-tube evaporator for carbon dioxide has been investigated both by experiment and simulation. Inside refrigerant heat transfer and outside heat and mass transfer of a wet surface heat exchanger were modeled using appropriate correlations. The results estimated by the calculation were in good agreement with the experimental results. The simulation errors were less than 7.9% for estimating capacity, 0.6℃ for air exit temperature, 1.2% for air exit humidity and 17% for CO2 exit pressure. The simulation program was used to study the effect of air flow direction, number of rows and refrigerant circuits. For a 2-row evaporator, parallel flow showed better performance for low air velocity but for high air velocity, counterflow was better. Refrigerant circuits, however, showed insignificant effect on the performance.