摘要
废沥青混合料在加热融化的过程中会形成大量有机烟气,加之搅拌引起的灰尘,使得沥青热再生路面养护车产生的废气成分复杂,单一手段难以净化去除。提出一种多级联合处理的除尘系统结构设计方法,包含旋风段、喷淋段和吸附段,通过多级分段处理实现对复杂成分废气的高效净化;基于有限元方法评估该系统结构在各阶模态下的频率、应变和模态振型,优化系统设计薄弱结构;重点针对具备尘气分离功能的旋风段结构,运用FLUENT软件对其内部流场特性、湍流强度、切向速度和速度场矢量进行分析及优化,以提高除尘系统除尘效率和净化效果。结果表明:随着旋风段分离器排气管深度的增加,静压分布和气流切向速度越对称且稳定,其内部中心气旋的切向速度也不断减小,避免了沉降的灰尘被再次扬起,提高尘气分离效率;同时,考虑湍流强度和湍流耗散增大,当排气管深度超过筒体高度时,压力损失逐步减弱,当排气管深度设计为筒体高度时效果最佳,此时旋风段分离器对直径1~10μm灰尘的分离效率可达94.3%。
Asphalt hot recycling pavement maintenance vehicle is a kind of special vehicle equipment which can heat waste asphalt locally to realize mixture mixing and old asphalt recycling. Generally, a large amount of organic flue gas will be formed during the heating and melting of waste asphalt mixture, coupled with the dust caused by mixing, which makes the complex composition of waste gas generated by asphalt hot recycled pavement maintenance vehicle. It is difficult to purify and remove by a single method. This paper presents a structural design method of multi-stage combined treatment of dust removal system, including cyclone section, spray section and adsorption section. The high-efficiency purification of complex component waste gas is realized through multi-stage and segmented treatment. Based on the finite element method, the frequency, strain and modal shape of the system structure under each mode are evaluated, and the weak structure of the system is further optimized. Focusing on the cyclone section structure with dust gas separation function, the flow field characteristics, turbulence intensity, tangential velocity and velocity field vector are analyzed by FLUENT software in order to improve the dust removal efficiency and purification effect. The results show that with the depth increase of the exhaust pipe of the cyclone separator, the more symmetrical and stable of the static pressure distribution and the tangential velocity of the air flow will be realized, and the tangential velocity of the central cyclone will also decrease. So it can avoid the settled dust from being lifted up again and the dust gas separation efficiency will be improved. At the same time, considering the increase of turbulence intensity and dissipation, when the depth of exhaust pipe exceeds the cylinder height, the pressure loss will gradually weaken. When the depth of exhaust pipe is designed as the cylinder height, the effect is the best and its separation efficiency of cyclone separator for diameter dust can reach 94.3%.
作者
梁栋
张嘉俊
吴鹏
LIANG Dong;ZHANG Jiajun;WU Peng(School of electromechanical and vehicle engineering,Chongqing Jiaotong University,Chongqing 400074,China;Zhejiang Metong Machinery Manufacture Co.,Ltd.,Jiaxing 314423,China)
出处
《重庆理工大学学报（自然科学）》
CAS
北大核心
2022年第9期50-58,共9页
Journal of Chongqing University of Technology：Natural Science
基金
国家自然科学基金项目(52175042)
重庆市教委科学技术研究青年项目(KJQN201900736)
城市轨道交通车辆系统集成与控制重庆市重点实验室开放课题(CKLURTSIC-KFKT-202005)。
关键词
除尘系统
有机废气
结构设计
模态分析
CFD
dust removal system
organic waste gas
structural design
modal analysis
CFD
