{"title":"微通道散热器热边界层传热系数的测量","authors":"Mehrdad Mehrvand, S. Putnam","doi":"10.1109/ITHERM.2016.7517588","DOIUrl":null,"url":null,"abstract":"This study describes the use of optical pump-probe diagnostics to characterize the heat transfer coefficient (HTC) in a developing thermal boundary layer in a microchannel. We use a differential form of the anisotropic time-domain thermoreflectance (TDTR) technique to measure the HTC as a function of fluid flow rate (or Reynolds number, Re). The testing environment/geometry consists of single-phase, degassed water flowing in a rectangular microchannel (hydraulic diameter Dh ≅ 480 μm) with local spot heating by the pump TDTR laser beam. Relative to the HTC measured with non-flowing (static) fluids, we find a 30% increase in the HTC for single-phase water flowing at Re ~ 1800.","PeriodicalId":426908,"journal":{"name":"2016 15th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"4","resultStr":"{\"title\":\"Heat transfer coefficient measurements in the thermal boundary layer of microchannel heat sinks\",\"authors\":\"Mehrdad Mehrvand, S. Putnam\",\"doi\":\"10.1109/ITHERM.2016.7517588\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"This study describes the use of optical pump-probe diagnostics to characterize the heat transfer coefficient (HTC) in a developing thermal boundary layer in a microchannel. We use a differential form of the anisotropic time-domain thermoreflectance (TDTR) technique to measure the HTC as a function of fluid flow rate (or Reynolds number, Re). The testing environment/geometry consists of single-phase, degassed water flowing in a rectangular microchannel (hydraulic diameter Dh ≅ 480 μm) with local spot heating by the pump TDTR laser beam. Relative to the HTC measured with non-flowing (static) fluids, we find a 30% increase in the HTC for single-phase water flowing at Re ~ 1800.\",\"PeriodicalId\":426908,\"journal\":{\"name\":\"2016 15th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm)\",\"volume\":\"7 1\",\"pages\":\"0\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2016-05-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"4\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"2016 15th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm)\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1109/ITHERM.2016.7517588\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"2016 15th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm)","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/ITHERM.2016.7517588","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Heat transfer coefficient measurements in the thermal boundary layer of microchannel heat sinks
This study describes the use of optical pump-probe diagnostics to characterize the heat transfer coefficient (HTC) in a developing thermal boundary layer in a microchannel. We use a differential form of the anisotropic time-domain thermoreflectance (TDTR) technique to measure the HTC as a function of fluid flow rate (or Reynolds number, Re). The testing environment/geometry consists of single-phase, degassed water flowing in a rectangular microchannel (hydraulic diameter Dh ≅ 480 μm) with local spot heating by the pump TDTR laser beam. Relative to the HTC measured with non-flowing (static) fluids, we find a 30% increase in the HTC for single-phase water flowing at Re ~ 1800.