Dynamic Modeling and Parameter Identification of a Selective Catalyst Reduction (SCR) System

• Main Authors: Tzung-Hua Tsai, 蔡宗樺
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/97707512820803266199

碩士 === 國立臺灣科技大學 === 機械工程系 === 102 === The urea-water-solution based selective catalyst reduction (SCR) system is one of the effective device in reducing the NOx emission of diesel engines. For the purpose of control synthesis and design, a zero dimensional dynamic model is developed in this thesis for a selective catalyst reduction system. In the absence of NH3 measurement, a procedure is proposed for identification of all the reaction constants. The states in this model include the concentration of NOx and NH3 and the surface coverage rate of the catalyst. The temperature-dependent reactions considered in this model include the adsorption, desorption and oxidation of NH3 and the NOx reduction. In the parameter identification process, the chemical reactor data provided by KJ company is first used for identification of the NOx reduction constants. The engine test data are then used for identification of the reaction constants for the adsorption, desorption, oxidation and the surface coverage rate of the catalyst. Finally, the SCR model is validated against steady-state and transient data at various engine modes and urea injection rate.