Flow and Temperature Visualization of a Heated Vortex Ring Using Temperature Sensitive Particle

• Main Authors: Chun-Yao Lin, 林雋堯
• Other Authors: Wei-Hsin Tien
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/98775u

碩士 === 國立臺灣科技大學 === 機械工程系 === 105 === A whole-field flow and temperature measurement technique is proposed in this study to visualize the temperature and flow distribution of a heated vortex ring. This technique is a combination and extension of Temperature Sensitive Paint (TSP) and Flow Visualization (FV). 5μm tracer particles are coated with EuTTA (Europium (III) thenoyltrifluoroacetonate, trihydrate) through a heating and stirring process to be fluorescent and temperature sensitive (TS). Unlike other researches using crystalline thermal phosphor as tracing particles, the particles proposed in this study is in spherical shape. The emission spectrum of EuTTA and the temperature response curve is verified by a spectrometer. To validate the performance of the temperature sensitive particles, TS-particles are seeded in DI water and injected into a cold water tank at 23℃ from a syringe to create a heated (70℃) and unheated (23℃) vortex ring. Through a 405nm excitation laser source, the 619nm emission luminescence signal is captured and recorded by a sCMOS camera. The experimental results show that the vortex ring structures is visualized successfully and light intensities of the heated vortex ring image is 4.5 times larger than the unheated one because of the temperature differences. With appropriate illumination and calibration, this technique can be applied to quantitatively measure the velocity and temperature fields of the flow.