旋回流れを伴う円筒形燃焼器内流れの研究 : 第3報, 絞り比とその位置の影響

抄録

The most practical combustor is considered to be the continuous combustion type with swirling flow. With this type, it is easier to control combustor and reduce pollutants. In this study, swirling nonreacting flows are investigated in an axisymmetric test section with expansion ratio of D/d=2, sidewall expansion angle α=180°and swirl vane angle 45°, which can be equipped with contraction nozzles of area ratios C={1-(Dc/D)²: Dc : contraction nozzle diameter, D: test section diamerter} 0.0, 0.54, 0.74 and 0.89, and its contraction nozzle locations, Lc/D=1.5, 2.0 and 2.5. From these results, the present study has clarified the mechanism of recirculation zone and the characteristics of flow pattern for a contraction nozzle and the location of the contraction nozzle. Other characterestics such as the intensity of turbulence and power spectra in these zones are also clarified.