多蒸发器低温回路热管的运行特性

doi:10.16085/j.issn.1000-6613.2019-1278

摘要/Abstract

摘要：

回路热管（LHP）是柔性高效的两相流换热部件，通过工质的相变以及毛细芯的吸附作用实现高效传热。多蒸发器回路热管（MeLHP）是在其基础上通过多个蒸发器并联实现对多个热源的高效热收集与排散，适用于空间探测技术中多阵列红外探测器的制冷。本文试验样机采用包含三个蒸发器的多蒸发器回路热管结构，管路以气耦合方式并联，管线非对称布置，工作温区为170K，采用乙烷为相变换热工质。以单蒸发器回路热管的数据为参考，在不同的加热功率及加热方式下对多蒸发器回路热管进行运行特性的实验研究，并从补偿器工作特性出发研究其充液率对性能的影响。实验证明，该MeLHP样机运行过程中具有良好的热分享特性，负载热量在各蒸发器间互相分享，且该特性有方向性，与两相流的流动特性相关，表现为低流阻回路向高流阻回路分享为有效分享，反之会引起高流阻性能变差而容易失效，因而低流阻回路分配更多热负载，有利于热管运行；MeLHP的传热极限与单蒸发器回路热管相当，并且实验还验证了MeLHP补偿器的工作方式为单一补偿器工作，因而对MeLHP充装时应适当提高充液率，以获得与单回路热管一致的性能。该研究有助于多蒸发器回路热管运行规律的掌握，对实际应用的推动有促进作用。

关键词: 多蒸发器回路热管, 热分享特性, 两相流, 低温, 气液平衡

Abstract:

Loop heat pipe(LHP) is a kind of flexible and efficient two-phase flow heat transfer device, which can achieve high heat transfer efficiency through phase change of working fluid and adsorption capability of porous wick. The multi-evaporator loop heat pipe(MeLHP) is based on such structure of LHP with parallel connection of multiple evaporators to achieve efficient heat collection and dissipation of multiple heat sources, which is suitable for the cooling of multi-array infrared detectors in space exploration technology. The test prototype adopted the structure of a multi-evaporator loop heat pipe with three evaporators. The pipelines were connected in parallel by gas coupling and arranged asymmetrically. The working temperature was set to be 170K while ethane was used as working fluid. Taking the experimental data of single evaporator loop heat pipe as reference, the experimental study of MeLHP’s operating characteristics was conducted under different heating power and heating methods. Then the effect of liquid charging ratio on MeLHP‘s performance was experimentally studied based on working characteristics of compensation chambers. Experiments showed that the MeLHP prototype had good heat sharing characteristics during the operating. Heat load was effectively shared among the evaporators, but the magnitude of heat sharing behaved differently in different heat transfer directions which depend on flow characteristics of each pipeline. It was shown that sharing from lower flow resistance loop to higher flow resistance loop was effective. Instead, when heat was shared to lower resistance loop, the performance of MeLHP would be worse. Such heat sharing made MeLHP prone to failure. Therefore, allocating more heat load in lower flow resistance loop was conducive to heat pipe operation. The heat transfer limit of MeLHP was the same as that of single evaporator loop heat pipe. It was also verified that only one compensation chamber worked when MeLHP was on operation. So the fluid charging ratio of MeLHP should be increased appropriately to obtain equivalent performance with single loop heat pipe. The research is helpful to grasp the operating rules of MeLHP and to promote the practical application of MeLHP.

Key words: multi-evaporator loop heat pipe, heat sharing characteristics, two-phase flow, low temperature, vapor liquid equilibria

中图分类号:

TK172.4

鲁得浦,谢荣建,文佳佳. 多蒸发器低温回路热管的运行特性[J]. 化工进展, 2020, 39(4): 1235-1244.

Depu LU,Rongjian XIE,Jiajia WEN. Operating characteristics of multi-evaporator cryogenic loop heat pipe[J]. Chemical Industry and Engineering Progress, 2020, 39(4): 1235-1244.

图/表 16

图1 MeLHP样机结构及测温点布置

表1 MeLHP样机基本参数

类别	参数
蒸发器数目	3
设计温区/K	170
充装工质	乙烷
壳体、管线材料	紫铜
吸液芯材料	铜粉烧结
气体管线/mm	810/720/630
液体管线/mm	695/605/515
充液率	0.6/0.7

图2 MeLHP补偿器的两种工作模式

图3 MeLHP性能测试装置系统图

表2 回路热管内阻力系数计算公式

类别	阻力系数计算公式
圆管沿程阻力系数	$f = 64 R e ???????????? (R e ≤ 2300) 0.3164 R e 0.25 ??? (4000 ≤ R e ≤ 105)$
圆管弯头局部阻力系数	$ζ = 0.131 + 0.163 (d R) 72 θ 90 12$
分流三通管局部阻力系数	$直管 : ζ = 1 1 - α 2 - 1$ $侧管 : ζ = 2$
汇流三通管局部阻力系数^[11]	$直管 : ζ = 2 1 - δ b α + C 1 Δ λ π - 1 α 2$ $侧管 : ζ = - 1 + 4 - 2 δ b α + C 1 Δ λ π - 1 α 2$ 其中， $δ b = K α$ ； $K = 0.5$ ； $Δ λ = 0.0049$ ； $C 1 = 0.058 R e ??? (层流) 25 ~ 40 ??????? (湍流)$ （Langhaar公式）

表2 回路热管内阻力系数计算公式

类别	阻力系数计算公式
圆管沿程阻力系数	$f = 64 R e ???????????? (R e ≤ 2300) 0.3164 R e 0.25 ??? (4000 ≤ R e ≤ 105)$
圆管弯头局部阻力系数	$ζ = 0.131 + 0.163 (d R) 72 θ 90 12$
分流三通管局部阻力系数	$直管 : ζ = 1 1 - α 2 - 1$ $侧管 : ζ = 2$
汇流三通管局部阻力系数^[11]	$直管 : ζ = 2 1 - δ b α + C 1 Δ λ π - 1 α 2$ $侧管 : ζ = - 1 + 4 - 2 δ b α + C 1 Δ λ π - 1 α 2$ 其中， $δ b = K α$ ； $K = 0.5$ ； $Δ λ = 0.0049$ ； $C 1 = 0.058 R e ??? (层流) 25 ~ 40 ??????? (湍流)$ （Langhaar公式）

图4 MeLHP并联管路流量分配示意图

图5 MeLHP并联管路流阻网络图

表3 MeLHP各回路流阻计算

参数	蒸发器	计算值
毛细芯流动阻力（n=1）	E1	2.76×10⁴m^-1·s^-1
	E2	2.76×10⁴m^-1·s^-1
	E3	2.76×10⁴m^-1·s^-1
沿程阻力和局部阻力（n=2）	E1	2.82×10⁴m^-1·kg^-1
	E2	3.27×10⁴m^-1·kg^-1
	E3	0.783×10⁴m^-1·kg^-1

图6 单蒸发器回路热管运行曲线

图7 MeLHP单蒸发器加热过程运行曲线（充液率0.6）

表4 MeLHP单蒸发器加热15W的稳态运行特性（充液率0.6）

温差/K

图8 MeLHP定总加热功率15W运行曲线（充液率0.6）

表5 MeLHP不同加热功率分配方式的稳态运行特性（充液率0.6）

实验工况	E1温差/K	E2温差/K	E3温差/K	平均温差/K	热阻/K·W^-1	蒸发器间最大温差/K
5W+5W+5W	18.76	19.16	18.23	18.71	1.24	0.93
0W+5W+10W	7.95	9.70	8.08	8.57	0.57	1.75
10W+5W+0W	21.69	24.51	10.64	18.95	1.26	13.88
10W+10W+0W	33.27	39.62	17.05	29.98	1.50	22.57
10W+0W+15W	35.21	32.40	36.65	32.11	1.39	4.25
10W+5W+10W	29.81	失效	29.97	E2失效
10W+10W+10W	31.21	失效	32.84	E2失效

表6 15W总功率不同分配方式的稳态运行特性（充液率0.7）

实验工况	E1温差/K	E2温差/K	E3温差/K	平均温差/K	热阻/K·W^-1	蒸发器间最大温差/K
0W+0W+15W	16.68	16.93	17.84	17.15	1.14	2.13
5W+0W+10W	18.17	17.64	18.54	18.17	1.20	1.05
0W+5W+10W	16.48	18.62	19.66	18.25	1.22	3.18
5W+5W+5W	22.72	21.84	23.68	22.74	1.52	1.84
10W+0W+5W	22.71	21.41	23.32	24.82	1.65	1.91
15W+0W+0W	26.70	22.86	23.73	24.43	1.63	3.84
10W+5W+0W	29.25	32.97	25.26	29.16	1.94	7.71
5W+10W+0W	23.67	31.53	25.33	26.84	1.79	7.86
0W+15W+0W	27.60	35.97	25.23	29.60	1.97	8.37

图9 两种充液率条件下MeLHP传热性能与蒸发器均温性对比

表7 高加热功率下不同分配方式的稳态运行特性（充液率0.7）

实验工况	温差/K E1	温差/K E2	温差/K E3	平均温差/K	热阻/K·W^-1	蒸发器间最大温差/K
0W+0W+20W	18.83	19.10	20.94	19.62	0.98	2.11
0W+0W+25W	20.61	20.87	22.77	21.42	0.86	2.16
0W+0W+30W	19.90	20.19	22.08	20.72	0.69	2.18
0W+0W+40W	23.73	23.96	26.06	24.58	0.61	2.33
0W+0W+50W	66.95	67.03	68.78	67.58	1.35	1.83
0W+0W+60W	E3失效
10W+0W+40W	66.71	66.80	68.37	67.29	1.35	1.66
10W+5W+35W	E2失效

参考文献 11

1	何江, 苗建印, 张红星, 等. 航天器深低温热管技术研究现状及发展趋势[J]. 真空与低温, 2018, 24(1): 1-8.
	HE Jiang, MIAO Jianyin, ZHANG Hongxing, et al. Current status and development trend of cryogenic heat pipe technologies in spacecraft[J]. Vacuum & Cryogenics, 2018, 24(1): 1-8.
2	陶汉中, 张红, 庄骏. 槽道吸液芯热管的研究进展[J]. 化工进展, 2010, 29(3): 403-412.
	TAO Hanzhong, ZHANG Hong, ZHUANG Jun. Progress in the theoretical study on miniature axial grooved heat pipe[J]. Chemical Industry and Engineering Progress, 2010, 29(3): 403-412.
3	张程宾, 施明恒, 陈永平, 等. “Ω”形轴向槽道热管的流动和传热特性[J]. 化工学报, 2008, 59(3): 544-550.
	ZHANG Chengbin, SHI Mingheng, CHEN Yongping, et al. Flow and heat transfer characteristics of heat pipe with axial “Ω”-shaped grooves[J]. CIESC Journal, 2008, 59(3): 544-550.
4	张畅, 谢荣建, 孙琦, 等. 液氮温区Ω形轴向槽道热管的启动特性与传热性能[J]. 化工进展, 2019, 38(6): 2610-2617.
	ZHANG Chang, XIE Rongjian, SUN Qi, et al. Start-up and heat transfer performance of a nitrogen cryogenic axial Ω shape grooved heat pipe[J]. Chemical Industry and Engineering Progress, 2019, 38(6): 2610-2617.
5	QU Y, WANG S, TIAN Y. A review of thermal performance in multiple evaporators loop heat pipe[J]. Applied Thermal Engineering, 2018, 143: 209-224.
6	MAYDANIK Y F, PASTUKHOV V G, CHERNYSHOVA M A, et al. Development and test results of a multi-evaporator-condenser loop heat pipe[C]//AIP Conference Proceedings, 2003.
7	BUGBY D C. Development and testing of a miniaturized multi-evaporator hybrid loop heat pipe[C]//AIP Conference Proceedings, 2005.
8	HOANG T T, KU J. Multiple-evaporator loop heat pipe[C]//53rd AIAA Aerospace Sciences Meeting. Florida, USA. 2015: 0709.
9	陈健, 张华, 巨永林. 多蒸发器CPL热管及纳米流体应用于热管的研究进展[J]. 低温与超导, 2011, 39(8): 42-48.
	CHEN Jian, ZHANG Hua, JU Yonglin. Recent development of multi-evaporator CPL heat pipe and nano-fuild applied to heat pipe[J]. Cryogenics & Superconductivity, 2011, 39(8): 42-48.
10	刘成志, 杨帆, 董德平, 等. 乙烷双蒸发器低温回路热管的实验研究[J]. 低温与特气, 2012, 30(3): 7-11.
	LIU Chengzhi, YANG Fan, DONG Deping, et al. Experimental investigation on ethane double-evaporator cryogenic loop heat pipe[J]. Low Temperature and Specialty Gases, 2012, 30(3): 7-11.
11	茅泽育, 赵凯, 赵璇, 等. 管道汇流口局部阻力试验研究[J]. 水利学报, 2007, 38(7): 812-818.
	MAO Zeyu, ZHAO Kai, ZHAO Xuan, et al. Experimental study on local flow resistance at junctions of circular pipes[J]. Journal of Hydraulic Engineering, 2007, 38(7): 812-818.

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