湿工况下圆形和椭圆形肋片管蒸发器热质传递特性研究*
Heat and mass transfer characteristics of evaporators with circular and elliptic finned tube under wet conditions
摘要：
通过焓差法实验研究了湿工况下圆形和椭圆形肋片管蒸发器的热工性能，发现在相同条件下椭圆形肋片管的换热量比圆形的高57.15%。建立了蒸发器内湿空气的热质传递计算模型，与实验和其他文献结果的最大误差均小于20%。经过对2种管型速度场、流线场、温度场和浓度场的分析，结果表明，虽然湿空气绕流圆形和椭圆形肋片管后均形成尾流，但椭圆形肋片管的流线型结构使气流到达第2排管的最大速度比圆形肋片管高约50%。因此椭圆形肋片管蒸发器的传热量更多、水蒸气冷凝速度更快，性能更好。
Abstract：
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.
Keywords:heatandmasstransfer,circularfinnedtube,ellipticfinnedtube,evaporator,wetcondition,speciestransport