Topics in Catalysis

, Volume 60, Issue 3–5, pp 225–229 | Cite as

Real-time Simulation of Dual-Layer Catalytic Converters Based on the Internal Mass Transfer Coefficient Approach

  • J. Rink
  • B. Mozaffari
  • S. Tischer
  • O. Deutschmann
  • M. Votsmeier
Original Paper


A new numerically efficient simulator for dual layer catalysts is implemented and its performance is demonstrated using the example of the dual layer ammonia oxidation catalyst. For the solution of the radial mass balances, each washcoat layer is represented by a single volume element and the diffusive mass fluxes into and within the washcoat are computed based on the concept of the internal mass transfer coefficients. The performance of the new simulator is compared against a reference simulator that fully resolves the concentration profiles in the washcoat. For a steady state test case, the error introduced by the new solution scheme is below 2 % for all relevant exhaust components. For a transient test case, the deviations become more significant. For the simulation of a WHTC, the maximum deviation in the NH3 outlet concentration is 23.3 %, whereas the cumulated NH3 emissions deviate by 10.6 %.With the new simulator, the 1800 s of the transient WHTC cycle can be simulated within 53 s on a standard laptop, 30 times faster than real time.


Exhaust gas aftertreatment Diffusion limitation Real-time simulation Mass transfer coefficient 


  1. 1.
    Scheuer A, Hauptmann W, Drochner A, Gieshoff J, Vogel H, Votsmeier M (2012) Dual layer automotive ammonia oxidation catalysts: Experiments and computer simulation. Appl Catal B 111–112:445–455CrossRefGoogle Scholar
  2. 2.
    Colombo M, Nova I, Tronconi E (2012) A simplified approach to modeling of dual-layer ammonia slip catalysts. Chem Eng Sci 75:75–83CrossRefGoogle Scholar
  3. 3.
    Colombo M, Nova I, Tronconi E, Schmeisser V, Bandl-Konrad B, Zimmermann LR (2013) Experimental and modeling study of a dual-layer (SCR + PGM) NH3 slip monolith catalyst (ASC) for automotive SCR after treatment systems. Part 2. Validation of PGM kinetics and modeling of the dual-layer ASC monolith. Appl Catal B 142–143:337–343CrossRefGoogle Scholar
  4. 4.
    Joshi SY, Harold MP, Balakotaiah V (2009) On the use of internal mass transfer coefficients in modeling of diffusion and reaction in catalytic monoliths. Chem Eng Sci 64:4976–4991CrossRefGoogle Scholar
  5. 5.
    Kumar P, Makki I, Kerns J, Grigoriadis K, Franchek M, Balakotaiah V (2012) A low-dimensional model for describing the oxygen storage capacity and transient behavior of a three-way catalytic converter. Chem Eng Sci 73:373–387CrossRefGoogle Scholar
  6. 6.
    Joshi SY, Ren Y, Harold MP, Balakotaiah V (2011) Determination of kinetics and controlling regimes for H2 oxidation on Pt/Al2O3 monolithic catalyst using high space velocity experiments. Appl Catal B 102:484–495CrossRefGoogle Scholar
  7. 7.
    Kumar P, Gu T, Grigoriadis K, Franchek M, Balakotaiah V (2014) Spatio-temporal dynamics of oxygen storage and release in a three-way catalytic converter. Chem Eng Sci 111:180–190CrossRefGoogle Scholar
  8. 8.
    Balakotaiah V (2008) On the relationship between aris and sherwood numbers and friction and effectiveness factors. Chem Eng Sci 63:5802–5812CrossRefGoogle Scholar
  9. 9.
    Mozaffari B, Tischer S, Votsmeier M, Deutschmann O (2016) A 1D modelling approach for dual-layer monolithic catalyst performance simulation. Chem Eng Sci 139:196–210CrossRefGoogle Scholar
  10. 10.
    Scheuer A, Drochner A, Gieshoff J, Vogel H, Votsmeier M (2012) Runtime efficient simulation of monolith catalysts with a dual-layer washcoat. Catal Today 188:70–79CrossRefGoogle Scholar
  11. 11.
    Bissett E (2015) An asymptotic solution for washcoat pore diffusion in catalytic monoliths. Emiss Control Sci Technol 1:3–16CrossRefGoogle Scholar
  12. 12.
    Scheuer A, Votsmeier M, Schuler A, Gieshoff J, Drochner A, Vogel H (2009) NH3-slip catalysts: experiments versus mechanistic modelling. Top Catal 52:1847–1851CrossRefGoogle Scholar
  13. 13.
    Schuler A, Votsmeier M, Kiwic P, Gieshoff J, Hautpmann W, Drochner A, Vogel H (2009) NH3-SCR on Fe zeolite catalysts—from model setup to NH3 dosing. Chem Eng J 154:333–340CrossRefGoogle Scholar
  14. 14.
    Opitz B, Bendrich M, Drochner A, Vogel H, Hayes R, Forbes J, Votsmeier M (2015) Simulation study of SCR catalysts with individually adjusted ammonia dosing strategies. Chem Eng J 264:936–944CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • J. Rink
    • 1
    • 2
  • B. Mozaffari
    • 3
  • S. Tischer
    • 3
  • O. Deutschmann
    • 3
  • M. Votsmeier
    • 2
  1. 1.Technische Universität DarmstadtDarmstadtGermany
  2. 2.Umicore AG & Co. KGHanauGermany
  3. 3.Karlsruher Institut für TechnologieKarlsruheGermany

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