摘要
用有限单元法建立了气冷器稳态分布参数模型,并通过实验对模型的准确性进行了验证。运用该模型对小型CO_2制冷系统用气冷器的传热性能、系统内的假临界现象及平均密度进行了研究,结果表明:在质量流量相同时,进口温度的变化对气冷器换热的影响很小,对气冷器管内假临界状态的出现位置影响很小;在气冷器进口温度相同时,质量流量越大,假(准)临界点出现的位置越向后移,当质量流量足够大时,气冷器内可能不会有假临界现象发生;气冷器进、出口处CO_2的算术平均密度值与气冷器内真实平均密度值相近,而对数平均密度和平方平均密度与气冷器内CO_2的真实平均密度值相差较大。
Steady-state distributed parameter model of gas cooler was established using the finite ele- ment method, and the accuracy of model was verified by experiment. The heat transfer performance of gas cooler,pseudo critical condition and the average density of refrigerant for a small refrigeration system were researched based on the model. The results showed that the change of entrance temperature has little effect on the heat exchanger and the pseudo critical state position the gas cooler for the same mass flow. The posi- tion of pseudo critical point-in-time moves backward with the increasing mass flow rate at the same entrance temperature. When the mass flux is large enough, it may be have no pseudo critical phenomenon at the gas cooler. The arithmetic average density of refrigerant in the inlet and outlet of gas cooler is similar to the ac- tual value. The difference between the logarithmic mean density and actual average density is larger than that between square average density and actual average density.
出处
《低温工程》
CAS
CSCD
北大核心
2016年第2期26-31,37,共7页
Cryogenics
基金
上海市动力工程多相流动与传热重点实验室(1N-15-301-101)
低温余热有机朗肯循环试验台项目
安徽工业大学青年基金(QZ201510)项目
关键词
气冷器
CO2
仿真
小型制冷系统
gas cooler
carbon dioxide
simulation
small refrigeration system
作者简介
沈航，男，25岁，硕士研究生。
