Effects of inlet supercooling and pressure on throttling behavior of liquid nitrogen

doi:10.11949/0438-1157.20201526

Abstract

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

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

CLC Number:

TB 61

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.

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.

Figures/Tables 15

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

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

Fig.3 Throttle parts

Fig.4 Logic of pressure control

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

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

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

Fig.6 Relationship of temperature drop and subcooling

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

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

Fig.9 Relationship between cooling capacity and inlet subcooling

Fig.10 Relationship between temperature drop and inlet pressure

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

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

Fig.13 Relationship between cooling capacity and inlet pressure

References 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.

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