节流前过冷度和压力对液氮节流特性的影响

doi:10.11949/0438-1157.20201526

摘要/Abstract

摘要：

节流在普冷领域应用广泛。其在基于林德循环、克劳德循环等低温液化循环、焦汤氦制冷系统、低温推进剂热力排气系统中也都有涉及。为了深入揭示低温流体相比室温气体的节流特殊性，设计并搭建了一套低温流体气液两相节流可视化试验系统。针对渐缩渐扩管型的节流元件，分析了节流前过冷度和压力对液氮节流特性的影响。研究表明：节流前压力一定，节流后温降及气相质量分数随节流前过冷度增加而增加；节流前过冷度一定，节流后温降及气相质量分数随节流前压力增大而增大；增大节流前压力，减小节流前过冷度，会减少节流后流体的单位质量制冷量。

关键词: 节流, 过冷度, 可视化, 低温助推剂, 热力学排气系统

Abstract:

Throttling is widely used in refrigeration, and is also involved in cryogenic liquefaction cycles such as Linde cycle, Claude cycle, J-T helium refrigeration cycle, and cryogenic propellant thermodynamic vent systems. In order to reveal the particularity of throttling effect of cryogenic fluids compared to ambient temperature gases and refrigerants, an experimental setup was designed and established to visualize two-phase cryogenic fluid throttling process. Taking a Laval nozzle as the testing element, the effects of inlet subcooling and pressure on throttling behavior of liquid nitrogen were investigated. The study showed that at given certain inlet pressure, the temperature drop and gas mass fraction increase with the inlet subcooling degree; at given certain inlet subcooling, the temperature drop and gas mass fraction increase with inlet pressure; higher inlet pressure and lower subcooling lead to lower refrigerating capacity.

Key words: throttling, subcooling, visualization, cryogenic fluid, thermodynamic vent system

中图分类号:

TB 61

赵芷慧, 李鹏, 吴栋梁, 张宏彬, 孙培杰, 黄永华. 节流前过冷度和压力对液氮节流特性的影响[J]. 化工学报, 2021, 72(S1): 106-112.

ZHAO Zhihu, LI Peng, WU Dongliang, ZHANG Hongbin, SUN Peijie, HUANG Yonghua. Effects of inlet supercooling and pressure on throttling behavior of liquid nitrogen[J]. CIESC Journal, 2021, 72(S1): 106-112.

图/表 15

图1 低温节流过程气液两相流可视化试验系统1—增压氮气瓶;2—液氮气瓶;3—低温调压阀;4—液氮过冷器;5—可编程控制器(PLC);6—计算机;7—数据采集仪;8—LED光源;9—真空测试腔;10—高速相机;11—分子泵机组;12—质量流量计;13—背压调节阀;14—回收罐;15—节流部件;16—压力传感器;17—铂电阻温度传感器

Fig.1 Visualized experimental system for gas-liquid two-phase flow in cryogenic throttling process

图2 低温节流过程气液两相流可视化试验系统实物

Fig.2 Actual experiment set-up for gas-liquid two-phase flow in cryogenic throttling process

图3 节流部件尺寸

Fig.3 Throttle parts

图4 压力控制逻辑

Fig.4 Logic of pressure control

表1 低温节流可视化试验台主要测量设备

Table 1 Main measuring equipment

设备名称	型号	主要参数	设备名称	型号	主要参数
铂电阻压力传感器	Pt100 CYYZ11	精度±78 mK，量程77~300 K 精度±0.1% FS，量程0~1 MPa	低温科里奥利流量计	RCCS34-A01D4SL/LT/S2	精度±0.1%，量程0.0015~5 t/h
差压传感器	CYYZ3051	精度±0.1% FS，量程0~1 MPa	低温调压阀	TokoT-8020	DN10，-196℃使用，Cv=1.1
LED光源	140 mm×140 mm	色温6000 K，照度50000 lx	数据采集仪	Keithley2700+770板卡	精度：六位半
PLC	欧姆龙CP1E-NA20DT-D	24 V，2路模拟量输出	高速相机	NAC-GX3相机	帧率198000fps，连续变焦比12

表2 试验工况设置

Table 2 Experimental conditions

工况	节流前压力/kPa	节流前过冷度/K	工况	节流前压力/kPa	节流前过冷度/K
1	420	0.2	10	480	3
2	480	0.2	11	490	3
3	520	0.2	12	510	3
4	380	2	13	360	4
5	440	2	14	480	4
6	470	2	15	490	4
7	490	2	16	420	5
8	420	3	17	430	5
9	440	3	18	440	5

图5 气液两相液氮节流过程状态点

Fig.5 Schematic diagram of gas-liquid two-phase liquid nitrogen throttling process

图6 温降与节流前过冷度的关系

Fig.6 Relationship of temperature drop and subcooling

图7 不同过冷度下节流温降

Fig.7 Schematic diagram of temperature drop in throttling process with different inlet subcooling

图8 气相质量分数与节流前过冷度的关系

Fig.8 Relationship between mass fraction of gas phase and inlet subcooling

图9 单位质量制冷量与节流前过冷度的关系

Fig.9 Relationship between cooling capacity and inlet subcooling

图10 温降与节流前压力的关系

Fig.10 Relationship between temperature drop and inlet pressure

图11 不同节流前压力温降过程

Fig.11 Schematic diagram of temperature drop in throttling process with different inlet pressure

图12 气相质量分数与节流前压力关系

Fig.12 Relationship between mass fraction of gas phase and inlet pressure

图13 单位质量制冷量与节流前压力关系

Fig.13 Relationship between cooling capacity and inlet pressure

参考文献 13

1	李家鹏, 陈晓屏, 陈军, 等. 微型节流制冷器在低温医疗中的发展与应用[J]. 真空与低温, 2014, 20(6): 311-314.
	Li J P, Chen X P, Chen J, et al. Development and application of a miniature Joule-Thomson cooler in cryosurgical [J]. Vacuum and Cryogenics, 2014, 20(6): 311-314.
2	李家鹏, 陈晓屏, 陈军, 等. 红外用微型节流制冷器耗气量试验研究[J]. 真空与低温, 2016, 22(3): 148-152.
	Li J P, Chen X P, Chen J, et al. Experimental research on gas consumption of a Joule-Thomson cooler for IR-detectors [J]. Vacuum and Cryogenics, 2016, 22(3): 148-152.
3	Mer S, Thibault J P, Corre C. Thermodynamic control system for cryogenic propellant storage: experimental and analytical performance assessment [C]// Proceedings of the 69th Annual Meeting of the APS Division of Fluid Dynamics. Portland, United States, 2016.
4	Hord J, Anderson L M, Hall W J. Cavitation in liquid cryogens (I): Venturi: CR-2045 [R]. NASA Contractor Reports, 1972.
5	Hord J. Cavitation in liquid cryogens (Ⅱ): Hydrofoil: CR-2156 [R]. NASA Contractor Reports, 1973.
6	Hord J. Cavitation in liquid cryogens (Ⅲ): Ogives: CR-2242 [R]. NASA Contractor Reports, 1973.
7	Edmonds D K, Hord J. Cavitation in liquid cryogens [M]// Advances in Cryogenic Engineering. Boston, MA: Springer US, 1969: 274-282.
8	Tani N, Nagashima T. Cryogenic cavitating flow in 2D Laval nozzle [J]. Journal of Thermal Science, 2003, 12(2): 157-161.
9	Niiyama K, Hasegaea S, Tsuda S, et al. Thermodynamic effects on cryogenic cavitating flow in an orifice [C]// Porceeding of the 7th International Symposium on Cavitation. Ann Arbor, Michigan, USA, 2009.
10	de Ohira K, Nakayama T, Nagai T. Cavitation flow instability of subcooled liquid nitrogen in converging-diverging nozzles [J]. Cryogenics, 2012, 52(1): 35-44.
11	赵东方. 液氮文氏管汽蚀动态特性可视化试验研究[D]. 杭州: 浙江大学, 2016.
	Zhao D F. Experimental observation on dynamic characteristic of liquid nitrogen cavitation in venture tube [D]. Hangzhou: Zhejiang University, 2016.
12	赵东方, 朱佳凯, 徐璐, 等. 文氏管中低温流体汽蚀过程可视化试验研究[J]. 低温工程, 2015, (6): 56-61.
	Zhao D F, Zhu J K, Xu L, et al. Visualization experiment of cavitating flow of cryogenic fluid in venturi tube [J]. Cryogenics, 2015, (6): 56-61.
13	朱佳凯. 低温空化非稳态特性和机理研究[D]. 杭州: 浙江大学, 2018.
	Zhu J K. Study on unsteady characteristics and mechanisms of cryogenic cavitation [D]. Hangzhou: Zhejiang University, 2018.

[1]	周绍华, 詹飞龙, 丁国良, 张浩, 邵艳坡, 刘艳涛, 郜哲明. 短管节流阀内流动噪声的实验研究及降噪措施[J]. 化工学报, 2023, 74(S1): 113-121.
[2]	胡香凝, 尹渊博, 袁辰, 是赟, 刘翠伟, 胡其会, 杨文, 李玉星. 成品油在土壤中运移可视化的实验研究[J]. 化工学报, 2023, 74(4): 1827-1835.
[3]	颜少航, 赖天伟, 王彦武, 侯予, 陈双涛. 微间隙内R134a空化可视化实验研究[J]. 化工学报, 2023, 74(3): 1054-1061.
[4]	孙雄康, 李强. 多级复合芯结构的强化沸腾传热研究[J]. 化工学报, 2022, 73(3): 1127-1135.
[5]	曹海亮, 张红飞, 左潜龙, 安琪, 张子阳, 刘红贝. 梯形微槽道表面池沸腾换热性能研究[J]. 化工学报, 2021, 72(8): 4111-4120.
[6]	沈超, 刘玉娟, 王竹萱, 张东伟, 杨建中, 魏新利. 平行流热管管内两相流动可视化实验研究[J]. 化工学报, 2021, 72(5): 2506-2513.
[7]	李梦钖, 高明, 左启蓉, 章立新, 赵玉刚. 过冷壁面液滴中四丁基溴化铵水合物生成的可视化研究[J]. 化工学报, 2021, 72(4): 2094-2101.
[8]	田永生, 季万祥, 陈增桥, 王乃华. 大长径比垂直换热管外瞬态池沸腾的研究[J]. 化工学报, 2021, 72(4): 2018-2026.
[9]	常志昊, 崔晓钰, 耿晖, 佘海龙. 两种印刷电路板式微通道节流制冷器性能实验研究[J]. 化工学报, 2021, 72(4): 2027-2037.
[10]	刘洁妤, 龚岩, 吴晓翔, 郭庆华, 于广锁, 王辅臣. 多喷嘴对置式气化炉内颗粒挥发分火焰可视化研究[J]. 化工学报, 2021, 72(3): 1275-1282.
[11]	杨宽, 阎昌琪, 曹夏昕. 自然循环窄矩形通道内过冷沸腾两相摩擦阻力特性[J]. 化工学报, 2020, 71(7): 3060-3070.
[12]	车健, 江锦波, 李纪云, 彭旭东, 马艺, 王玉明. 节流孔出气模式对静压干气密封稳态性能影响[J]. 化工学报, 2020, 71(4): 1734-1743.
[13]	汪彬, 李江道, 黄永华, 吴静怡, 王天祥, 雷刚. 节流参数对液氮贮箱热力排气系统运行特性的影响[J]. 化工学报, 2019, 70(S2): 101-107.
[14]	王辉辉, 张丹, 杨庆忠, 牛照程. 纯水静态闪蒸中液膜高度演变的实验研究[J]. 化工学报, 2019, 70(S1): 54-60.
[15]	王慧儒, 刘振宇, 姚元鹏, 吴慧英. 组合相变材料强化固液相变传热可视化实验[J]. 化工学报, 2019, 70(4): 1263-1271.