Thermal performance of pulsating heat pipe for high power LED thermal management

doi:10.11949/0438-1157.20240556

Abstract

Abstract:

Pulsating heat pipe (PHP) can effectively solve the thermal management problem of high heat flux electronic components. However, its application is severely limited by its poor adaptability to heat sources with high heat flux in small areas, poor gravity resistance and large contact thermal resistance. In this paper, a butterfly PHP is designed, which has a more compact evaporation section and is suitable for high heat flux in a small area. Taking LED cooling as the application background, the thermal performance of butterfly PHP under different working conditions (heating power, different working fluid, installation angle, liquid filling rate) was studied, and the performance of LED chip thermal management system based on butterfly PHP was analyzed. The results show that under the condition of natural convection condensation, butterfly PHP shows excellent heat transfer performance and temperature equalization, and can meet the thermal management requirements of Bridgelux 100 W LED chip at any installation angle, with the highest thermal resistance not exceeding 0.292 K/W, which has great application potential. Heating power significantly affects the thermal performance of PHP. Increasing the power can restrain the amplitude of wall temperature pulsation and improve the periodicity of wall temperature pulsation. There is a critical power, and the performance of butterfly PHP is better when the heating power is greater than this power and deionized water is charged. Heating power and installation angle both affect the optimal filling rate, and they have certain interaction.

Key words: pulsating heat pipe, thermal management, heat transfer, flow, experimental validation

摘要：

为满足大功率LED芯片的热管理需求，设计了蝶形脉动热管（pulsating heat pipe，PHP），实验研究了不同工况下（加热功率、工作流体、安装角度、充液率）的传热性能，基于热阻法分析了蝶形PHP的热管理性能。结果表明，自然对流冷凝工况下，蝶形PHP表现出优秀的传热性能和均温性，任意安装角度下，均能够满足Bridgelux 100W LED芯片的散热需求，热阻不超过0.292 K/W，最低可达0.174 K/W，均温性系数低至0.263。加热功率显著影响PHP的传热性能，提高功率能够抑制壁温脉动幅度，增强脉动周期性。存在一个交叉功率，大于此功率后充注去离子水的蝶形PHP性能更好。加热功率和安装角度均会影响最佳充液率，二者具有一定的交互作用。

关键词: 脉动热管, 热管理, 传热, 流动, 实验验证

CLC Number:

TK 79

Xinze LI, Shuangxing ZHANG, Guanyu REN, Rui HONG, Wenjing DU. Thermal performance of pulsating heat pipe for high power LED thermal management[J]. CIESC Journal, 2024, 75(S1): 126-134.

李新泽, 张双星, 任冠宇, 洪瑞, 杜文静. 大功率LED热管理用脉动热管热性能[J]. 化工学报, 2024, 75(S1): 126-134.

Figures/Tables 17

Fig.1 Butterfly PHP structure

Fig.2 Simulation of LED heat source

Fig.3 Butterfly PHP structure and performance test platform

Table 1 Experimental test conditions

变量	数值
工作流体	去离子水、丙酮
加热功率/W	0~120（间隔20）
充液率/%	30、40、45、50、60
内径/外径/mm	2/3
安装角度/(°)	0、30、60、90

Table 2 Uncertainty of parameters

参数	最大相对不确定度
充液率/%	2.5%
加热功率/W	0.14%
PHP热阻/(K/W)	4.8%

Fig.4 Analysis of heat transfer process

Fig.5 Wall temperature fluctuation characteristics (FR=50%, α=90°)

Fig.6 Thermal resistance (FR=50%, α=90°)

Fig.7 Temperature equalization coefficient (FR=50%, α=90°)

Fig.8 Critical power(FR=50%, α=90°)

Fig.9 Evaporation-condensation temperature difference (FR=50%, α=90°)

Fig.10 Start-up performance of different FR (α=90°)

Fig.11 Thermal resistance (deionized water)

Fig.12 Thermal resistance (deionized water, Q=80 W)

Fig.13 Temperature equalization coefficient (deionized water, Q=80 W)

Fig.14 Tmax (heating condition of Bridgelux 100 W LED)

Fig.15 Thermal resistance of each heat transfer link (heating condition of Bridgelux 100 W LED, FR=45%)

References 33

15	Zhang M, Yang H H, Yin Y, et al. Start-up and heat transfer characteristics of a pulsating heat pipe with graphene oxide nanofluids[J]. CIESC Journal, 2022, 73(3): 1136-1146.
16	Zhou Y, Yang H H, Liu L W, et al. Enhancement of start-up and thermal performance in pulsating heat pipe with GO/water nanofluid[J]. Powder Technology, 2021, 384: 414-422.
17	杨洪海, 张苗, 刘利伟, 等. 氧化石墨烯/水脉动热管传热强化及性能预测[J]. 化工进展, 2022, 41(4): 1725-1734.
	Yang H H, Zhang M, Liu L W, et al. Heat transfer performance enhancement and prediction in GO/water pulsating heat pipe[J]. Chemical Industry and Engineering Progress, 2022, 41(4): 1725-1734.
18	Rudresha S, Babu E R, Thejaraju R. Experimental investigation and influence of filling ratio on heat transfer performance of a pulsating heat pipe[J]. Thermal Science and Engineering Progress, 2023, 38: 101649.
19	Shi W X, Li M, Chen H D, et al. Effect of evaporating-condensing length ratio and heat flux on starting and operating characteristic of pulsating heat pipe[J]. Applied Thermal Engineering, 2024, 246: 122963.
20	Mucci A, Kholi F K, Chetwynd-Chatwin J, et al. Numerical investigation of flow instability and heat transfer characteristics inside pulsating heat pipes with different numbers of turns[J]. International Journal of Heat and Mass Transfer, 2021, 169: 120934.
21	Dai Y C, Zhang R, Qin Z Y, et al. Research on the thermal performance and stability of three-dimensional array pulsating heat pipe for active/passive coupled thermal management application[J]. Applied Thermal Engineering, 2024, 245: 122793.
22	Jang D S, Ham S H, Shin H H, et al. Thermal performance improvement of a radial pulsating heat pipe with diverging channels by adopting Tesla valves at various heat fluxes[J]. Applied Thermal Engineering, 2024, 237: 121799.
23	Zhang D, Wang L, Xu B R, et al. Experimental and simulation study on flow heat transfer characteristics of flat pulsating heat pipe with wide and narrow interphase channels[J]. Applied Thermal Engineering, 2024, 245: 122806.
24	Yang H H, Wang J, Wang N, et al. Experimental study on a pulsating heat pipe heat exchanger for energy saving in air-conditioning system in summer[J]. Energy and Buildings, 2019, 197: 1-6.
25	Shang F M, Yang Q J, Fan S L, et al. Experimental study on novel pulsating heat pipe radiator for horizontal CPU cooling under different wind speeds[J]. Thermal Science, 2022, 26(1 Part B): 449-462.
1	Holonyak N, Bevacqua S F. Coherent (visible) light emission from Ga(As1-xPx) junctions[J]. Applied Physics Letters, 1962, 1(4): 82-83.
2	Juntunen E, Tapaninen O, Sitomaniemi A, et al. Copper-core MCPCB with thermal vias for high-power COB LED modules[J]. IEEE Transactions on Power Electronics, 2014, 29(3): 1410-1417.
3	Kyatam S, Camacho P, Rodrigues L, et al. Thermal analysis of high power LEDs using different PCB materials[C]//2017 European Conference on Circuit Theory and Design (ECCTD). Catania, Italy: IEEE, 2017: 1-4.
4	Li J, Lin F, Wang D M, et al. A loop-heat-pipe heat sink with parallel condensers for high-power integrated LED chips[J]. Applied Thermal Engineering, 2013, 56(1/2): 18-26.
5	Ben Abdelmlek K, Araoud Z, Charrada K, et al. Optimization of the thermal distribution of multi-chip LED package[J]. Applied Thermal Engineering, 2017, 126: 653-660.
6	Ben Abdelmlek K, Araoud Z, Ghnay R, et al. Effect of thermal conduction path deficiency on thermal properties of LEDs package[J]. Applied Thermal Engineering, 2016, 102: 251-260.
7	Wang C, Yuan K J, Song Q, et al. Performance of pulsating heat pipe with a stimulus of auxiliary heat load for battery thermal management system[J]. International Journal of Heat and Mass Transfer, 2024, 223: 125190.
8	Solanki A, Kapadia R G. Review of the effect of foldability and working fluid on the performance of flexible pulsating heat pipe for foldable applications[J]. Materials Today: Proceedings, 2023, 82: 234-240.
9	Kholi F K, Park S, Yang J S, et al. A detailed review of pulsating heat pipe correlations and recent advances using artificial neural network for improved performance prediction[J]. International Journal of Heat and Mass Transfer, 2023, 207: 124010.
10	Fan Y C, Wang Z G, Guo J W, et al. Capture of kinetic behavior of ethanol-based copper oxides in pulsating heat pipe[J]. International Journal of Heat and Mass Transfer, 2024, 225: 125392.
11	Wang L P, Cai Y, Zhan H R. Lorenz-like equation of two-phase flow in a single closed loop pulsating heat pipe[J]. International Journal of Thermal Sciences, 2023, 186: 108132.
12	Xu Y Y, Xue Y Q, Qi H, et al. An updated review on working fluids, operation mechanisms, and applications of pulsating heat pipes[J]. Renewable and Sustainable Energy Reviews, 2021, 144: 110995.
13	Lyu B K, Xu D, Wang W, et al. Experimental investigation of a serial-parallel configuration helium pulsating heat pipe[J]. Cryogenics, 2023, 131: 103668.
14	赵佳腾, 吴晨辉, 戴宇成, 等. 脉动热管强化传热及其应用研究进展[J]. 化工学报, 2022, 73(2): 535-565.
	Zhao J T, Wu C H, Dai Y C, et al. Research progress on heat transfer enhancement and application of oscillating heat pipe[J]. CIESC Journal, 2022, 73(2): 535-565.
15	张苗, 杨洪海, 尹勇, 等. 氧化石墨烯/水脉动热管的启动及传热特性[J]. 化工学报, 2022, 73(3): 1136-1146.
26	Chen Y, He Y Q, Zhu X Q. Flower-type pulsating heat pipe for a solar collector[J]. International Journal of Energy Research, 2020, 44(9): 7734-7745.
27	Mahajan G, Cho H, Smith A, et al. Experimental analysis of atypically long finned oscillating heat pipe for ventilation waste heat recovery application[J]. Journal of Thermal Science, 2020, 29(3): 667-675.
28	张双星, 刘舫辰, 张义飞, 等. R-134a脉动热管相变蓄放热实验研究[J]. 化工学报, 2023, 74(S1): 165-171.
	Zhang S X, Liu F C, Zhang Y F, et al. Experimental study on phase change heat storage and release performance of R-134a pulsating heat pipe[J]. CIESC Journal, 2023, 74(S1): 165-171.
29	Lv L C, Li J, Zhou G H. A robust pulsating heat pipe cooler for integrated high power LED chips[J]. Heat and Mass Transfer, 2017, 53(11): 3305-3313.
30	Wang H, Qu J, Peng Y Q, et al. Heat transfer performance of a novel tubular oscillating heat pipe with sintered copper particles inside flat-plate evaporator and high-power LED heat sink application[J]. Energy Conversion and Management, 2019, 189: 215-222.
31	Lin Z R, Wang S F, Huo J P, et al. Heat transfer characteristics and LED heat sink application of aluminum plate oscillating heat pipes[J]. Applied Thermal Engineering, 2011, 31(14/15): 2221-2229.
32	林梓荣. 自激式振荡流热管热输送性能研究[D]. 广州: 华南理工大学, 2012.
	Lin Z R. Study on heat transport capability of self-exciting mode oscillating-flow heat pipe[D]. Guangzhou: South China University of Technology, 2012.
33	李新泽, 张双星, 杨洪海, 等. 基于电池冷却用新型脉动热管性能的实验研究[J]. 化工学报, 2024, 75(6): 2222-2232.
	Li X Z, Zhang S X, Yang H H, et al. Experimental study on performance of new type of pulsating heat pipe for battery cooling[J]. CIESC Journal, 2024, 75(6): 2222-2232.

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