PIV Measurement for Flow Field Analysis of Diffusion Flame over a Porous Cylindrical Burner
Date Issued
2014
Date
2014
Author(s)
Guo, Chang-Gang
Abstract
The present study is aimed to understand the dynamic characteristics of flow field and flame downstream from the porous cylindrical burner. A Particle Image Velocimetry (PIV) system was built to analyze the flow field qualitatively and quantitatively. In this research, the fuel flow rate is fixed while the upstream wind speed is set to 0.4 m/s (Re=24.85), 0.9 m/s (Re=77.55), 1.9 m/s (Re=157.3), 2.4 m/s (Re=199). The chemiluminescence images and the flame temperature distribution was compared with PIV. Influences on flow field pattern and structure of flame for four flame types could be investigated.
When the flame type is envelope flame, a low speed region is formed downstream from the porous cylinder. There is no recirculation zone exist because the effect of buoyancy. The flame in the forward stagnation region was unable to sustain where air went into the interior of cylindrical directly when wind speed enhanced. A small region of recirculation zone where fuel can be mixed with air was observed in both side of cylinder where 〖C_2〗^* fluorescent reaction here is bleaker. We observed that there is a pair of large scale vortex could bring intermediate products and wasted heat to reaction zone behind the cylinder when the flame type is wake flame. We also observed that the shape of yellow flame front which looks like a concave curve downward is contributed to effect of recirculation zone. The range of recirculation zone was extended when the wind speed got higher. Thus the yellow flame was unable to be sustained due to the high velocity of recirculation zone. However, air and fuel were mixed more efficiently in recirculation zone and reacted on both sides of cylinder, then brings blue flame layer formed on both sides of the porous cylinder burner.
Subjects
粒子影像測速儀 擴散火焰
化學螢光法
多孔圓柱燃燒器
強制對流
迴流區
SDGs
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-103-R01522315-1.pdf
Size
23.54 KB
Format
Adobe PDF
Checksum
(MD5):d40bcc26fcbee00188c9234a8ffe073d