Basic flow fields of two dimensional V flames were examined as a preliminary work to study the instability of premixed flame with vorticity generation. Laminar premixed propane and methane flames were anchored by a thin and electrically heated wire to make two dimensional V flames. Various flame shapes were observed by changing equivalence ratio from 0.45 to 0.92 and mean velocity from 20cm/s to 100cm/s. Flow fields were measured mainly by PIV(Particle Image velocimetry) and the results were compared with those obtained by LDV(Laser Doppler velocimetry) to confirm their reliability. With the observations that the curvatures of V flames are so small except the neighborhood of anchoring point, V flames were locally assumed to be inclined planar flames in gravitational field and the measured flow fields were locally compared with those of analytical solutions, which showed the qualitatively similar results. In downstream region, the vorticity fields were nearly constant except region near the center line, which support the assumption of locally one dimensional flame. Besides, from the geometrical simplicity of V flames, it was tried to find experimentally the similarity of flow fields in downstream region. Finally, stability diagrams of propane and methane flames were drawn for the equivalence ratio less than one and the wide range of mean velocity.
와도를 생성시키는 예혼합 화염의 불안정에 대한 선행연구로써 이차원 V 화염의 기본 유동장을 연구하였다. 당량비 0.45에서 0.92, 그리고 평균유속 20cm/s에서 100cm/s까지 관찰되었고, 유동장은 PIV와 LDV를 이용해 측정되었다. 열선 부근를 제외한 V 화염의 곡률이 매우 작기 때문에, 이차원 V 화염을 중력장하에서의 기울어진 일차원 평면화염으로 가정할 수 있다. 따라서, 측정된 유동장은 국부적으로 해석해와 비교 되었고, 정성적으로 유사한 거동을 보였다. 또한 화염대 하류에서의 와도를 유동장을 통해 계산 되었고, 해석해와 정성적으로 유사한 거동을 보였다. 마지막으로 프로판 및 메탄 화염의 안정화 선도가 관찰되었다.
