摘要
通过建立空调蒸发器分布参数模型,并对模型进行了验证,进而研究了四种不同风速场对R22和R290翅片管蒸发器流动和换热性能的影响规律。研究表明:在上三角型、下三角型和三角型风速场分布下,蒸发器单位面积换热量、质量流量以及压降均较均匀风速场降低;上三角型较均匀型单位面积换热量下降达7%左右,下三角型和三角型较均匀型下降4%左右;在不同风速场下,各换热温差基本持平,总传热系数起主导作用;R290质量流量均较R22小40%左右,且压降均较R22小24%左右。在满足换热量的要求下,R290在协调压降与质量流量具有一定的优势,可以作为现有空调制冷剂R22的环保型替代工质。
A distributed parameter model for air - conditioning evaporator has been developed in this paper. The model has been validated by comparing outputs from the model with test data, given in reference papers. The effects of four different velocity fields on the flow and heat transfer of R22 and R290 finned - tube evaporator are comparatively analyzed. The results show that the specific heat load, dae mass flow rate and the pressure drop of evaporator under three types velocity field labeled upper triangle, lower triangular and triangular type are all decreasing than that of the uniformity velocity field type. Using the uniformity type as a reference, the upper triangle, lower triangular, and triangular type, all have a lower specific heat load by 7%, 4% and 4%, respectively. With differenct velocity fields, the different temperature differences are nearly identical with each other, and the coefficient of heat transfer acts as the dominant factor in the heat transfer process. The mass flow rate of R290 is less than 40% around than that of R22, and the pressure drop is less than 24% around. When the heat flux of the system is contented, R290 has the particular advantages in terms of harmonizing the pressure drop with the mass flow rate and can be used as environment friendly alternative refrigerant for R22 air- conditioning.
出处
《低温与超导》
CAS
CSCD
北大核心
2009年第10期26-31,39,共7页
Cryogenics and Superconductivity
基金
国家"863"基金项目(2007AA05Z219)资助
关键词
翅片管蒸发器
性能
风速场
不均匀分布
Finned - tube evaporator, Performance, Wind velocity field, Maldistrlbution
