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The Study on the Effects of Mixer Configurations on Fluid Mixing Characteristics in SCR Systems  

Seo, Jin-Won (Department of Mechanical Engineering, Graduate School, Ajou University)
Lee, Kyu-Ik (Department of Mechanical Engineering, Graduate School, Ajou University)
Oh, Jeong-Taek (Department of Mechanical Engineering, Graduate School, Ajou University)
Choi, Yun-Ho (Department of Mechanical Engineering, Graduate School, Ajou University)
Lee, Jong-Hwa (Department of Mechanical Engineering, Ajou University)
Park, Jin-Il (Department of Mechanical Engineering, Ajou University)
Publication Information
Transactions of the Korean Society of Automotive Engineers / v.16, no.6, 2008 , pp. 192-199 More about this Journal
Abstract
The key issues for the reduction technologies of the exhaust gas from diesel engine being developed are to reduce particulate matters and NOx. The SCR system is known to be one of the most efficient and stable technologies to remove NOx through the mixing of NOx and urea solution. In the present research, the effects of mixer configurations of SCR system have been investigated to enhance the SCR performance. First, a Schlieren technique is employed to visualize the mixing characteristics of urea solution and exhaust gas. The results show that a mixer is essential to obtain proper fluid mixing. In addition, numerical studies have been made to understand the mixing characteristics through the comparison of the mal-distribution index of concentration at the several locations of the diffuser. In particular, the effects of number of blade and mixer angles on mixing characteristics were studied. The results show that the blade angle has a larger effect on the mixing characteristics than the number of blades.
Keywords
Selective catalytic reduction; NOx; Mixer; Schlieren technique; Sauter mean diameter; Spray model; CFD;
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