하이브리드타입 프랙탈격자 화염의 난류특성에 관한 실험적 연구
An Experimental Study on Turbulent Characteristics of Hybrid Type Fractal Grid Flames
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초록
This study focuses on the V-shape with hybrid type fractal grid generator to evaluate the turbulent characteristics of turbulent premixed flames. In this work, the mean and velocity fluctuation, turbulence intensity were investigated. The integral length scale of non-reactive flow was additionally investigated to obtain a Borghi-Peters diagram. By comparing the Borghi-Peters diagram shown as a result of the non-reactive flow based with the reaction OH-PLIF images, it was confirmed that the flame characteristics of each regimes in fractal grid flames were well represented. Also, the irreguar turbulence of premixed flames was quantitatively analyzed using the flame brushes obtained by the mean progress variable analysis. As a result, the flame brushes of the hybrid type fractal turbulence generator were wider than the conventional fractal grid generator with individuial shape of cross and square grid. This means that the turbulence intensity has increased compared to the previous conventional fractal grid, and the local displacement speed is also expected to increase.it has increased compared to the existing fractals of the hybrid type, and the local displacement speed is also expected to increase.
Abstract
This study focuses on the V-shape with hybrid type fractal grid generator to evaluate the turbulent characteristics of turbulent premixed flames. In this work, the mean and velocity fluctuation, turbulence intensity were investigated. The integral length scale of non-reactive flow was additionally investigated to obtain a Borghi-Peters diagram. By comparing the Borghi-Peters diagram shown as a result of the non-reactive flow based with the reaction OH-PLIF images, it was confirmed that the flame characteristics of each regimes in fractal grid flames were well represented. Also, the irreguar turbulence of premixed flames was quantitatively analyzed using the flame brushes obtained by the mean progress variable analysis. As a result, the flame brushes of the hybrid type fractal turbulence generator were wider than the conventional fractal grid generator with individuial shape of cross and square grid. This means that the turbulence intensity has increased compared to the previous conventional fractal grid, and the local displacement speed is also expected to increase.it has increased compared to the existing fractals of the hybrid type, and the local displacement speed is also expected to increase.
참고문헌 (24)
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