Experimental and 3D, embedded modeling for diesel engine SCR deposit

  • F. QianEmail author
  • L. Lü
  • T. Feng
  • D. Yang


Nowadays, the selective catalytic reduction (SCR) is a promising solution to fulfill stringent nitrogen oxide (NOX) emission standards enforced by worldwide regulation bodies for lean burning engines. However, in the practical operation, urea deposits occur under unfavorable conditions, which bring about a failure of urea dosing strategy, affect the SCR system de-NOx performance and lowering the fuel economy by increasing the engine back pressure. This paper will present 3D deposit model, which can be used to predict the deposit position. Furthermore, a model-based controls strategy and calibration are designed. The comparison test results of both engine emission tests and vehicle field tests shows there is significant deposits improvement with the embedded model.

Key Words

Diesel engine Urea-SCR Deposit 3D model Embedded model 



selected catalyst reduction


nitrogen oxide


32.5 % urea solution


space velocity


cyanuric acid


NH3/NOX ratio


dosing control unit


european transient cycle


drag force


pressure force


frequency factor


droplet diameter


activation energy


universal gas constant


reynolds number


concentration of HCNO


film patch area


stanton number


mass of deposits


mass of wallfilm with low temperature


urea mass fraction in the wallfilm


limitation of Miller curve.


mass of the injected Adblue


percentage of injected Adblue to wallfilm


the mass of evaporated water


urea mass which involved in themolysis reaction


wallfilm density


the wallfilm volume


the wallfilm area


heat transfer coefficient.


wallfilm specific heat


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Copyright information

© The Korean Society of Automotive Engineers and Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  1. 1.Key Laboratory of High Performance Ship of Ministry of EducationWuhan University of TechnologyHubeiChina

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