摘要
文中介绍在跨临界CO_2制冷系统中采用的双节流装置,第一膨胀阀用来控制高压侧压力,第二膨胀阀用两相流引射器代替,以回收系统膨胀功。对双节流装置引射制冷系统的性能进行了实验研究,分析了两段式喷嘴几何尺寸和工况变化对引射器性能和系统COP的影响。实验结果表明,在固定工况下,随着第一喷嘴扩张角的增加,引射比和压缩机耗功先增大后减小,而系统制冷量和系统COP呈相反的趋势;随着第一喉部当量直径的增加,引射比和系统COP都先增大后减小。在固定几何尺寸下,蒸发温度为-1℃和-3℃时,系统COP和引射比分别取得最大值;随着气冷器出口压力的升高,引射比逐渐增加,而系统COP逐渐减小。
The double -throttling devices were adopted in the transcritical CO2 refrigeration system and introduced in this paper. The first expansion valve was used to control the high - side pressure, and the second expansion valve was replaced by a two - phase flow ejector to recover the system expansion work. The performance of the double - throttling ejector refrigeration sys- tem was conducted experimentally, and the influence of the geometries and working conditions on the performance of the ejector and the COP were analyzed. The experimental results indicate that under a fixed working condition, with the increase in the first nozzle divergence angle, the entrainment ratio and compressor power consumption firstly increase and then decrease, but the system cooling capacity and the COP have an opposite trend. With the rise in the equivalent diameter of the first throat, the entrainment ratio and the COP firstly increase then decrease. Under the fixed geometry size, as the evaporation temperature is - 1 ℃ and -3℃, the COP and the entrainment ratio reach the maximum value respectively. With the increase in the outlet pressure of the gas cooler, the entrainment ratio is on the rise, and the COP shows a downward trend.
作者
槐艳双
郭宪民
史耀广
Huai Yanshuang Guo Xianmin Shi Yaoguang(Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, Tianjin 300134, China)
出处
《低温与超导》
CAS
北大核心
2017年第4期78-81,共4页
Cryogenics and Superconductivity
基金
国家自然科学基金(51176142)
天津市应用基础及前沿技术研究计划项目(09JCZDJC24900)资助
关键词
双节流
CO2
引射比
系统COP
Double- Throttling, CO2, Entrainment ratio, System COP
