Heat and mass transfer characteristics of evaporators with circular and elliptic finned tube under wet conditions

Studies the thermal performance of circular and elliptic finned tube evaporators under wet conditions by enthalpy difference method. Reveals that the heat transfer of the elliptic finned tube is 57.15% higher than that of the circular one under the same conditions. Establishes a heat and mass transfer calculation model of wet air in evaporator, and the maximum error with the experimental and other literature results is less than 20%. Through the analysis of the velocity field, streamline field, temperature field and concentration field of the two kinds of tubes, the results show that although the wakes are both formed after the wet air flows around the circular and elliptic finned tubes, the streamline structure of the elliptic finned tube makes the maximum velocity of the air flow to the second row of tubes about 50% higher than that of the circular one. Therefore, the elliptic finned tube evaporator features higher heat transfer capacity, more rapid water vapor condensation and better performance.