Summary: | 碩士 === 國立交通大學 === 機械工程系所 === 102 === Steady state liquid crystal thermography was used to measure heat transfer in a one-pass rotating rectangular channel. The aspect ratio of the channel was 4:1 with two opposite walls roughened with pin fins. The test conditions of Reynolds number(Re) and rotation number(Ro) were in the range of 10000-20000 and 0-0.195, respectively. The diameter and height of the pin fins were 5mm and 5mm, respectively. A staggered array of pins with uniform streamwise and spanwise spacing(X/D=2,S/D=2) was installed.
Stroboscopy was used as the photography technique. This photography technique is able to record images when the channel is in rotating condition. The result showed that in stationary condition, the wake region behind the pin fins became narrower with increased Reynolds number. When the rotation number increased, the shape of the pin fin wake was shifted in different directions.
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