摘要
以旋涡流化床悬浮空间喷入二次风形成一强族流场和气固悬浮流动为物理模型，试验研究了从床面夹带到悬浮空间颗粒群的运动行为及气固两相浓度场的匹配。指出在气相强旋湍流的作用下，在近壁区形成一稳定的高浓度的颗粒悬浮层，颗粒在炉内的平均停留时间延长，气固滑移速度增大，两相混合强烈并充分接触，良好的空气动力结构对提高炭粒在悬浮空间的燃尽度．降低扬析可燃物损失十分有利。本文研究结果．对降低常规鼓泡床及抛煤机链条炉内的飞灰可燃物损失，提高悬浮空间的气流横向混合速率有重要参考价值。
With the help of a physical model featuring the injection of secondary air into a vortex fluidized bed suspension space to form a strong swirling-flow field and gas/solid suspension flow, an exPerimental study has been Performed of the motion behavior of the groups of particles entrained from the bed surface into the suspension space and the matching of gas/solid dual Phase concentration fields. It is observed thet under the action of gas phase strong vortex turbulent flows there emerged at the near-wall region a stable suspension layer of high-concentration particles.The average retention time of the Particles in the boiler is lengthened and gas/solid sliding speed increased, resuling in a strong dna] phase mixing and sufficient concoct, The proper aerodynamic structure exercises a very favorable effect on the enhancement of burning-down degree of carbon particles in the suspension space, bringing about a reduction of segregated combustible loss.The cold model experimental study results presented in this Paper can prove very helpful in lowering the flyash combustible loss occurring in conventional bUbbling fluidized bed and travellinggrate boilers equipped with coal spreaders and in enhencing the gas flow transverse mixing speed in the suspesion space.
出处
《热能动力工程》
CAS
CSCD
北大核心
1994年第4期206-209,220,共5页
Journal of Engineering for Thermal Energy and Power
关键词
旋涡流化床
旋风燃烧
动力学
燃煤锅炉
vortex fluidized bed, transverse mixing,cyclone combustion,classification
