3 Dimensional Unsteady Model of Monolith Catalytic Converter
Putranto Manuhoro, Widodo W Purwanto, Ahmad Indra S*
Gas and Petrochemical Engineering Dept
*Mechanical Engineering Dept
Faculty of Engineering Universitas of Indonesia
Kampus Baru UI, Depok 16424
 

ABSTRACT

Catalytic converter could be a solution in reducing car emission problem that has already been applied in vehicles recently. Catalytic converter showed poor performance when the engine is being started, and it would produce emission up to 80% of total emission. This condition could be disadvantages for car producers because their product can’t meet The Ultra Light Emission Vehicle (ULEV) standard.
To figure out the phenomena happened in catalytic converter when the engine is being started, chemical reaction model and mathematics model had to be built. The model would be 3 Dimensional in 2 Fase, solid and gas (3D2F). The main equations applied are momentum equation, continuity equation, mass and energy balance equations.
The model involved will be run in FLUENT software in unsteady condition. Eleven equations of chemical reaction model are adopted in FLUENT by using subroutine that called UDF, based in C++ language.
Because of the limitation in computing process and differences between physical phenomena and mathematic model, the chemical reaction will be simplified to be a reaction to convert CO to CO2. Results obtained for inlet at cold start shows that 100% CO could be converted in 0.05 seconds at 20 mm to 30 mm from inlet and it takes 9 seconds to obtain the wall temperature become steady.

RESULT

           Fig1. Temperatur vs time (s)                                               Fig2. Temperatur vs distance (mm)

Fig3. CO Conversion                                                        Fig 4. CO Concentration  Vs Time            

 FIg5. CO₂ Concentration Vs Time

Fig6. Contour CO Concentration on x = 5 mm