精馏型自复叠制冷系统的降温速度优化分析
Optimization and Analyses on the Cooling-down Rate of an Auto-cascade Refrigeration System Operating With a Rectifying Column
张靖鹏 1王勤 2宋琦 3罗介霖 2陈光明2
作者信息
- 1. 浙江大学制冷与低温研究所,浙江省制冷与低温技术重点实验室,杭州 310027;中国科学院微小卫星创新研究院,上海 201304
- 2. 浙江大学制冷与低温研究所,浙江省制冷与低温技术重点实验室,杭州 310027
- 3. 北京航天发射技术研究所,北京 100076
- 折叠
摘要
本文基于准稳态计算模型,提出了一种精馏型自复叠制冷系统降温速度的优化方法.以最大制冷量为优化目标,得到给定混合工质浓度时降温过程最佳吸气压力曲线,采用分段调节吸气压力的方法来匹配该曲线,从而减少降温时间,在此基础上可进一步优化混合工质浓度提高降温速度.该方法应用于箱内空气温度由20℃降至-100℃的试验箱降温过程,采用摩尔比例为0.35/0.25/0.15/0.25的R50/R1150/R290/R600a混合工质,结合最优吸气压力切换参数:两个切换温度(-20℃和-105℃)和三个切换压力(700 kPa、600 kPa和550 kPa)可以达到最短的降温时间.研究结果还表明不同蒸发温度区间所需的最优浓度不同,在降温过程中调节工质的浓度,则可以减少降温时间.该优化方法可为其它混合工质制冷系统降温过程研究提供参考.
Abstract
Based on a quasi-steady-state simulation model,a method to optimize the cooling-down rate of an auto-cascade refrigeration system operating with a rectifying column and multi-component mixed refrigerant is proposed in the paper.Targeted on the maximum cooling capacity,the opti-mal suction pressure-evaporating temperature curve for a specified mixed refrigerant concentration can be obtained,which can be matched by the sectional suction pressure adjustment in the prac-tical applications to reduce the overall cooling-down time,and the concentration of mixed refrig-erant can be optimized to further improve the cooling-down rate based on this way.The fastest overall cooling-down time is achieved using the R50/R1150/R290/R600a as the mixed refrigerant(0.35/0.25/0.15/0.25 by mole)and corresponding shifting parameters(including two shifting temper-atures-20℃ and-105℃)and three shifting suction pressure 700 kPa,600 kPa and 550 kPa)for the sectional suction pressure adjustment,when the air temperature in the test chamber is dropped from 20℃ to-100℃.Calculation results also show that the optimal concentrations are different for different evaporating temperatures,and the cooling-down rate can be improved further if the concen-tration of the mixed refrigerant can be adjusted during the cooling-down process.The optimization methods used in this paper can also provide references for researches on cooling-down processes of other refrigeration systems using multi-component mixed refrigerants.
关键词
混合工质/自复叠/精馏/降温过程/准稳态Key words
mixed refrigerant/auto-cascade refrigeration system/rectification/cooling-down pro-cess/quasi-steady-state引用本文复制引用
出版年
2024
NETL
NSTL
万方数据