프랙탈 난류생성판을 갖는 V-shape 화염에서 난류 예혼합 화염 분석: Part. I 비반응장의 난류유동 특성
Analysis of Turbulent Premixed Flames in V-shape Flames with Fractal Turbulence Generators: Part. I Turbulent Flow Characteristics in a Non-Reacting Field
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In this study, various fractal grids are used to investigate the non-reacting turbulent flow characteristics of a circular fractal turbulence generator. The types of fractal grids used as turbulence generators are cross and square, and a total of 24 grids produced by changing the shape parameters are investigated. Also, to compare the characteristics of turbulent flow, a general perforated plate with the same blockage ratio is used together. In the center axis turbulence component results, the two types of fractal grids show different turbulence component tendency depending on their shape parameters, and are investigated individually. As a result of quantitatively confirming the difference in turbulence intensity using the percentage difference method, the two types of fractal grids produced stronger turbulence than the conventional grids (perforated plate and mesh). The results of (r, z) plane measurements show that the shape of the turbulent generator significantly affects the turbulent component after nozzle exit. The inhomogeneity of the turbulence component was more severe in the square grid than in the cross and conventional grids, but as the blockage ratio of the square grid increased, the homogeneity of the turbulence component showed a tendency to improve.
Abstract
In this study, various fractal grids are used to investigate the non-reacting turbulent flow characteristics of a circular fractal turbulence generator. The types of fractal grids used as turbulence generators are cross and square, and a total of 24 grids produced by changing the shape parameters are investigated. Also, to compare the characteristics of turbulent flow, a general perforated plate with the same blockage ratio is used together. In the center axis turbulence component results, the two types of fractal grids show different turbulence component tendency depending on their shape parameters, and are investigated individually. As a result of quantitatively confirming the difference in turbulence intensity using the percentage difference method, the two types of fractal grids produced stronger turbulence than the conventional grids (perforated plate and mesh). The results of (r, z) plane measurements show that the shape of the turbulent generator significantly affects the turbulent component after nozzle exit. The inhomogeneity of the turbulence component was more severe in the square grid than in the cross and conventional grids, but as the blockage ratio of the square grid increased, the homogeneity of the turbulence component showed a tendency to improve.
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