Cloud-Based Optimization of Mixer Design for Urea/SCR Aftertreatment Systems

April 3, 2019 10:00 AM – 11:00 AM CDT


Nader Fateh, VP Business Development
ESTECO North America Inc

Adarsh Elango, Application Engineer
ESTECO North America Inc

Scott Drennan, Director of Aftertreatment Applications
Convergent Science, Inc.

Kislaya Srivastava, Research Engineer
Convergent Science, Inc.


Meeting NOx (NO + NO2) emissions regulations with aftertreatment system designs that are both effective and economical is critical to successful product performance. The favored approach to satisfying NOx emissions regulations in heavy- and light-duty diesel vehicles is to use a Selective Catalytic Reduction (SCR) device where ammonia catalyzes to reduce NOx. Urea injected as Diesel Exhaust Fluid (DEF) upstream of the SCR decomposes to produce ammonia, and the NOx reduction depends on the ammonia uniformity entering the SCR. Physical mixers are used in Urea/SCR systems to help the DEF spray decompose and mix to provide a more uniform distribution of ammonia. However, the mixer should not create a significant pressure drop, which has a negative effect on engine efficiency. Current industry trends are moving to more compact integrated Urea/SCR systems, which increases the need for an optimum mixer design that may be difficult to achieve with traditional design approaches. Combining fast and accurate CFD simulation with effective multi-objective optimization of the geometry has the potential to substantially improve the mixer designs and produce high levels of NOx reduction without a substantial backpressure penalty.

During the webinar we will describe how modeFRONTIER was used to drive CONVERGE in the optimization of a Urea/SCR flapper-type mixer by adjusting the flapper vane angles to achieve designs with both high NOx reduction and a low pressure drop. As will be demonstrated, the process produces optimum design candidates at a fraction of the cost that would be required with a traditional design approach.

CONVERGE CFD software, already an industry standard for internal combustion engine simulations, is increasingly being used for a variety of other applications, including modeling exhaust aftertreatment, gas turbine combustors, pumps, and compressors. CONVERGE provides fast and accurate solutions in 3D systems with coupled flow and chemistry and complex, moving geometries. Autonomous meshing capabilities remove the burden of mesh creation from the user, making CONVERGE ideal for geometry optimization studies.

modeFRONTIER, ESTECO’s state-of-the-art process integration and multi-objective design optimization platform, combines ease of use with powerful algorithms and advanced data visualization and statistical analysis tools. It is widely used across an extensive range of industries to conduct DOE campaigns, run design optimization studies and effectively post-process multi-dimensional data. Acting as a robot intelligently driving CAE tools, modeFRONTIER allows users to efficiently search the design space for optimum solutions to multi-objective and multi-disciplinary problems.

Who should attend:

  • Design engineers concerned about mitigating urea deposits in Urea/SCR systems
  • Engine aftertreatment system engineers
  • CFD modeling engineers for Urea/SCR systems
  • Product managers for powertrain and aftertreatment
  • Engineers and IT professionals interested in enabling CONVERGE simulations in the cloud