Application Study on a New Hybrid Canning Structure of After-Treatment System for Diesel Engine

Based on the airflow rotation concept, a new packaging structure was designed to meet the performance requirements of China-VI stage emission regulations. The new structure is a hybrid structure of spiral space with small blades and conical plates. The Computational Fluid Dynamics (CFD) simulation was used to analyze the velocity uniformity and ammonia uniformity of the flow field, and the results showed that velocity uniformity and ammonia uniformity were higher than 0.95, and the possibility of crystallization risk was very low. The actual performance of the new structural prototype was verified by means of engine bench testing. The test results were excellent and the conversion efficiency reached 0.96. The new selective catalytic reduction (SCR) urea mixed structure design greatly improved the conversion efficiency of the after-treatment system and has excellent anti-crystallization performance.