仅值班供油时斜流驻涡燃烧室出口温度分布特性研究

Outlet Temperature Profile Characteristics of Mixed-Flow Trapped Vortex Combustor by Pilot-Fueling Only

关键词:  斜流驻涡燃烧室  出口温度分布  值班供油  火焰形态  高温区

Key words:  Mixed-flow trapped vortex combustor  Outlet temperature profile  Pilot-fueling  Flame morphology  High temperature zone

摘要:

为深入了解和掌握仅值班供油时斜流驻涡燃烧室出口温度分布特性，开展了不同进气速度和油气比下燃烧室出口温度径向分布、不均匀性及出口温度分布系数（OTDF）和出口径向温度分布系数（RTDF）的研究，并结合凹腔内火焰形态分析了出口温度分布特性的变化原因。结果表明，不同进气速度和油气比下出口温度径向分布都呈现为中间高、两端低，温度峰值在0.6倍燃烧室出口高度位置处；不同进气速度下，高温区整体偏向燃烧室出口中心上方；不同油气比下，高温区主要靠近燃烧室出口中心；随着进气速度增加，不均匀性、OTDF增大，高温区从燃烧室出口中心上方往中心偏移；随油气比增加，不均性减小，OTDF和RTDF基本都是先减小后缓慢上升，高温区从燃烧室出口中心下方偏移到中心上方；这与凹腔内燃烧情况息息相关，取决于燃油分布、后进气掺混作用、凹腔当地油气比和高温产物位置。

Abstract:

To deeply understand and grasp the outlet temperature profile characteristics of the mixed-flow trapped vortex combustor by pilot-fueling only， the research on parameters such as outlet radial temperature profile， non-uniformity， and outlet temperature distribution factor （OTDF） and radial temperature distribution factor （RTDF） under different inlet air velocities and fuel/air ratios was carried out. The reason for the change of the outlet temperature profile characteristics was analyzed by combined with the flame morphology in the cavity. The results show that the outlet radial temperature profile at different inlet air velocities and fuel/air ratios is high in the middle， low at both ends， and the temperature peak is at 0.6 times the height of the exit of the combustor. The high temperature zone is generally biased above the outlet center at different inlet air velocities. The high temperature zone is mainly located at the outlet center under different fuel/air ratios. As the inlet air velocity increases， the non-uniformity and OTDF increase， and the high temperature zone shifts from above the outlet center to the center. As the fuel/air ratio increases， the non-uniformity decreases， and OTDF and RTDF basically decrease first and then slowly increase， and the high temperature zone shifts from below the outlet center to above the outlet center. This is closely related to the combustion situation in the cavity， which depends on the fuel distribution， the driving-air mixing effect， the local fuel/air ratio in the cavity， and the location of high temperature products.