瑞士卷燃烧器中火焰位置影响因素的研究

Research of the Combustion Flame Position in a Small Swiss-Roll Combustor

对逆向对流换热通道瑞士卷（Swiss—roll）燃烧器内甲烷／空气的燃烧过程进行了模拟计算，结果表明只有将燃料控制在很窄的速度和当量比的范围内时，才能使火焰稳定在燃烧器的中心位置。流体流速较高时，由于强烈的对流换热预热效应，即使甲烷含量非常低也能维持稳定燃烧，但火焰始终停留在反应物通道的第一个拐角处；而流体流速较低时，Swiss—roll燃烧室内较长的逆向对流换热通道恰好将足够的热量从出口高温烟气处传递给入口冷流体，从而保持燃料在燃烧器中心区域的稳定燃烧，但由于预混燃料气体流量较小，只有在特定条件下（VO=1．0m／s时函=0．8—1．2，VO=0．5m／s时空：1．0）才能维持稳定的火焰。

A numerical model on methane/air combustion inside a small Swiss-roll combustor was set up to investigate the flame position of small-scMe combustion. The simulation results show that the combustion flame could be maintained in the central area of the combustor only when the speed and equivalence ratio are all within a narrow and specific range. For high inlet velocity, the combustion could be sustained stably even with a very lean fuel and the flame always stayed at the first corner of reactant channel because of the strong convection heat transfer and preheating. For low inlet velocity, small amounts of fuel could combust stably in the central area of the combustor, because heat was appropriately transferred from the gas to the inlet mixture. Whereas, for the low premixed gas flow, only in certain conditions （4 = 0.8-1.2 when v0 = 1.0 m/s, θ = 1.0 when v0 = 0.5 m/s） the small-scale combustion could be maintained.