导流片结构参数对先进旋涡燃烧室性能影响研究 *

Effects of Flow Guide Vanes Structure Parameters on Characteristics of Advanced Vortex Combustor

关键词:  先进旋涡燃烧室  导流片  双旋涡  数值模拟

Key words:  Advanced vortex combustor  Flow guide vanes  Dual-vortex  Numerical simulation

摘要:

为了研究带导流片的先进旋涡燃烧室燃烧及流动性能，对导流片不同结构参数下燃烧室的流场分布、温度分布、总压损失、燃烧效率及污染物排放进行了数值模拟。结果表明，带导流片的先进旋涡燃烧室性能表现出明显的优越性，能够在不依赖凹腔射流的情况下形成理想的双旋涡结构，有利于增强凹腔稳焰及燃气掺混，大幅度提高燃烧效率，改善出口温度分布，降低NO排放。导流片结构参数对燃烧室性能影响呈现出一定的规律。当导流片伸入凹腔的长度与前钝体高度之比(a/B)为0.2，导流片到前钝体上端面的距离与燃烧室进气通道高度之比(b/H)为0.4，导流片到前钝体后端面的距离与凹腔长度之比(c/L)为0.1～0.2时，燃烧室在贫燃条件下可以实现低压降、低污染的稳定燃烧，而且出口温度分布均匀。

Abstract:

In order to investigate the combustion and flow characteristics of Advanced Vortex Combustor (AVC) with flow guide vanes，the effects of different structural parameters on flow fields，temperature distribution，the total pressure loss，combustion efficiency and pollutant emission were numerically studied. The results show that AVC with flow guide vanes has better performance than formal AVC. It can form a desirable dual-vortex structure even without any cavity air injection and it can enhance the stability of flame and the mixing of gas，combustion efficiency and exit temperature distribution. Meanwhile it can reduce pollutant emission. Structural parameters of flow guide vanes have certain significant effects on the combustor characteristics. Stable combustion with lower total pressure loss and lower pollution can be achieved when a/B=0.2，b/H=0.4，c/L=0.1～0.2 (where a is defined as the length of vane inside the cavity，b is defined as the distance from vane to the upper surface of the front-body，c is the distance from vane to the rear surface of the front-body，B is the front-body height，H is height of the inlet，L is the cavity length)under lean conditions，and the combustor exit temperature distribution becomes more uniform.