{"title":"在不同模式下对不同蒸汽管道厚度的直式超薄蒸汽腔进行测试","authors":"","doi":"10.1016/j.applthermaleng.2024.124353","DOIUrl":null,"url":null,"abstract":"<div><p>This study aims to demonstrate, through careful temperature measurements and infrared images, that tests for a vapor chamber (VC) under a VC mode or a heat pipe (HP) mode, reach very different thermal performances due to different severities for water accumulation at the condenser end. Both modes have been frequently adopted in the literature with the difference overlooked. Experiments are conducted for 100 × 20 mm<sup>2</sup> straight ultra-thin vapor chambers (UTVCs) with a 0.17 mm or a 0.12 mm vapor duct thickness and a total thickness of 0.45 mm or 0.4 mm, respectively. Three different charges, an over-charge, a charge with the charge ratio slightly larger than 1.0, and an under-charge, are prepared for each vapor duct thickness. Severe water accumulation over the condenser is observed under the HP mode, yielding drastic temperature drops therein. Under the HP mode the maximum heat transfer rate (<em>Q</em><sub>max</sub>) drops to about only 3–4 W with vapor duct thickness (<em>h</em>) = 0.17 mm and fails at actual vapor input ∼3 W with <em>h</em> = 0.12 mm. Water accumulation cannot be totally removed in the HP mode when the UTVC is placed vertically, although slight improvement on the thermal performance can be achieved with the assistance of gravity. Under a HP mode, the minimum vapor chamber resistance (<em>R</em><sub>min</sub>) ranges between 0.7–1.0 K/W, while under a VC mode <em>R</em><sub>min</sub> is 0.14–0.29 K/W. <em>Q</em><sub>max</sub> appears slightly reduced for the thinner vapor duct thickness due to the larger vapor resistance.</p></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":6.1000,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Straight ultra-thin vapor chambers tested under different modes for different vapor duct thicknesses\",\"authors\":\"\",\"doi\":\"10.1016/j.applthermaleng.2024.124353\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>This study aims to demonstrate, through careful temperature measurements and infrared images, that tests for a vapor chamber (VC) under a VC mode or a heat pipe (HP) mode, reach very different thermal performances due to different severities for water accumulation at the condenser end. Both modes have been frequently adopted in the literature with the difference overlooked. Experiments are conducted for 100 × 20 mm<sup>2</sup> straight ultra-thin vapor chambers (UTVCs) with a 0.17 mm or a 0.12 mm vapor duct thickness and a total thickness of 0.45 mm or 0.4 mm, respectively. Three different charges, an over-charge, a charge with the charge ratio slightly larger than 1.0, and an under-charge, are prepared for each vapor duct thickness. Severe water accumulation over the condenser is observed under the HP mode, yielding drastic temperature drops therein. Under the HP mode the maximum heat transfer rate (<em>Q</em><sub>max</sub>) drops to about only 3–4 W with vapor duct thickness (<em>h</em>) = 0.17 mm and fails at actual vapor input ∼3 W with <em>h</em> = 0.12 mm. Water accumulation cannot be totally removed in the HP mode when the UTVC is placed vertically, although slight improvement on the thermal performance can be achieved with the assistance of gravity. Under a HP mode, the minimum vapor chamber resistance (<em>R</em><sub>min</sub>) ranges between 0.7–1.0 K/W, while under a VC mode <em>R</em><sub>min</sub> is 0.14–0.29 K/W. <em>Q</em><sub>max</sub> appears slightly reduced for the thinner vapor duct thickness due to the larger vapor resistance.</p></div>\",\"PeriodicalId\":8201,\"journal\":{\"name\":\"Applied Thermal Engineering\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":6.1000,\"publicationDate\":\"2024-09-04\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Applied Thermal Engineering\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1359431124020210\",\"RegionNum\":2,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ENERGY & FUELS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Thermal Engineering","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1359431124020210","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
引用次数: 0
摘要
本研究旨在通过仔细的温度测量和红外图像证明,由于冷凝器末端积水的严重程度不同,在汽化室(VC)模式或热管(HP)模式下进行的测试会产生截然不同的热性能。文献中经常采用这两种模式,但忽略了两者的区别。实验对象为 100 × 20 mm2 直式超薄蒸汽室(UTVC),蒸汽管道厚度分别为 0.17 mm 或 0.12 mm,总厚度分别为 0.45 mm 或 0.4 mm。为每种蒸汽管道厚度准备了三种不同的装料,即过量装料、装料比略大于 1.0 的装料和装料不足。在 HP 模式下,冷凝器上出现了严重的积水现象,导致温度急剧下降。在 HP 模式下,当蒸汽管道厚度(h)= 0.17 毫米时,最大传热速率(Qmax)仅为 3-4 W,而当蒸汽管道厚度(h)= 0.12 毫米时,实际蒸汽输入量为 3 W。在 HP 模式下,当UTVC 垂直放置时,虽然在重力的作用下可以略微改善热性能,但积水并不能完全排除。在 HP 模式下,最小蒸气室阻力(Rmin)在 0.7-1.0 K/W 之间,而在 VC 模式下,Rmin 为 0.14-0.29 K/W。由于蒸汽阻力较大,当蒸汽管道厚度较薄时,Qmax 会略有降低。
Straight ultra-thin vapor chambers tested under different modes for different vapor duct thicknesses
This study aims to demonstrate, through careful temperature measurements and infrared images, that tests for a vapor chamber (VC) under a VC mode or a heat pipe (HP) mode, reach very different thermal performances due to different severities for water accumulation at the condenser end. Both modes have been frequently adopted in the literature with the difference overlooked. Experiments are conducted for 100 × 20 mm2 straight ultra-thin vapor chambers (UTVCs) with a 0.17 mm or a 0.12 mm vapor duct thickness and a total thickness of 0.45 mm or 0.4 mm, respectively. Three different charges, an over-charge, a charge with the charge ratio slightly larger than 1.0, and an under-charge, are prepared for each vapor duct thickness. Severe water accumulation over the condenser is observed under the HP mode, yielding drastic temperature drops therein. Under the HP mode the maximum heat transfer rate (Qmax) drops to about only 3–4 W with vapor duct thickness (h) = 0.17 mm and fails at actual vapor input ∼3 W with h = 0.12 mm. Water accumulation cannot be totally removed in the HP mode when the UTVC is placed vertically, although slight improvement on the thermal performance can be achieved with the assistance of gravity. Under a HP mode, the minimum vapor chamber resistance (Rmin) ranges between 0.7–1.0 K/W, while under a VC mode Rmin is 0.14–0.29 K/W. Qmax appears slightly reduced for the thinner vapor duct thickness due to the larger vapor resistance.
期刊介绍:
Applied Thermal Engineering disseminates novel research related to the design, development and demonstration of components, devices, equipment, technologies and systems involving thermal processes for the production, storage, utilization and conservation of energy, with a focus on engineering application.
The journal publishes high-quality and high-impact Original Research Articles, Review Articles, Short Communications and Letters to the Editor on cutting-edge innovations in research, and recent advances or issues of interest to the thermal engineering community.