Heat Transfer Measurements for a Horizontal Micro-Tube Using Liquid Crystal Thermography

摘要：

In this study, a non-contact liquid crystal thermography (LCT) method was developed for surface temperature measurements on a horizontal 2000μm macro-tube and 1000μm micro-tube. In the single-phase heat transfer experiments, the fully-developed flow heat transfer data were obtained under the uniform wall heat flux boundary condition. In order to reduce the heat loss, the test tube was placed in a vacuum box. For comparison purposes, the tube surface temperatures were also measured using thermocouples (TC). The results showed that the heat transfer coefficient is affected by the vacuum condition (magnitude of vacuum pressure). For the micro-tube, the expected buoyancy effect was not observed in the laminar region when using the LCT method. The increase of heat transfer in the laminar region due to the surface roughness was also observed. In the turbulent region, the LCT heat transfer data trend was close to the classical correlation. For the entire flow regime, the TC heat transfer data trend was much higher than the LCT data trend due to the thermal shunt effect. Our current LCT results when compared with those of Yang and Lin 1 showed slightly higher heat transfer values.

关键词： Liquid Crystal Thermography (LCT) Thermocouple (TC) Micro-tube Heat transfer measurement

作者: Lap Mou Tam Hou Kuan Tam Afshin J. Ghajar Wa San Ng

作者单位: Department of Electromechanical Engineering, Faculty of Science and Technology, University of Macau, Department of Electromechanical Engineering, Faculty of Science and Technology, University of Macau, School of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, Oklahoma 0740

会议类型: 国际会议

会议名称: 4th International Symposium on Heat Transfer and Energy Conservation(第四届传热与节能国际研讨会 ISHTEC2012)

会议地点: 广州

会议语种:英文

页码: 1-5

在线出版日期: 2012-01-06（万方平台首次上网日期，不代表论文的发表时间）