微元管催化燃烧过程中燃烧特性分岔分析

Bifurcation analysis of catalytic combustion in micro-channel

运用分岔理论对微元管催化燃烧过程进行了详细的分岔分析,采用了一种比较理想的简化模型——短体蜂窝状模型(SM模型),同时微元管中气体流动采用了层流模型.分别以径向Thiele数及滞留时间为分岔参数对微元管催化燃烧过程中混合气的着火与熄火特性进行了详细分析,同时,详细讨论了B、P、Lef及s对混合气燃烧特性的影响.结果表明当以径向Thiele数为分岔参数时,随着Lef减小或B、P增大,主体气流与催化剂表面混合气的着火点与熄火点之间的非稳定区域将变宽;当以滞留时间为分岔参数时,随着s及B减小或Lef增大,催化剂表面混合气的着火点与熄火点之间的非稳定区域将变窄.

Bifurcation analysis of catalytic combustion in micro-channel was carried out using bifurcation theory. A simple model -- the short monolith model （SM model） and the laminar flow model were adopted. The bifurcation behaviors of the ignition and the extinction of the mixed gas were analyzed with the transverse Thiele modulus and the residence time as bifurcation parameter respectively. At the same time, the effects of the values of B, P, Lef and Фs on the bifurcation characteristics of the mixed gas combustion were discussed. The results show that with the transverse Thiele modulus as bifurcation parameter, the unstable steady region between the ignition and extinction of the fluid and mixed gas on the catalyst surface is widened with Lef decreasing or B and P increasing. With the residence time as bifurcation parameter, the unstable steady region between the ignition and extinction of the mixed gas on the catalyst surface becomes narrow with Фs and B decreasing or Lef increasing.