A conceptual design and numerical analysis of the mixerless urea-SCR system
| 1 | Faculty of Power and Aeronautical Engineering, Warsaw University of Technology, Poland |
CORRESPONDING AUTHOR
Bartosz KAŹMIERSKI
Faculty of Power and Aeronautical Engineering, Warsaw University of Technology, Warsaw, Poland
Faculty of Power and Aeronautical Engineering, Warsaw University of Technology, Warsaw, Poland
Submission date: 2021-07-14
Final revision date: 2021-07-26
Acceptance date: 2021-07-26
Online publication date: 2021-08-18
Publication date: 2021-10-15
Combustion Engines 2021,187(4), 12–20
KEYWORDS
TOPICS
ABSTRACT
In the present study, an innovative design of the urea-selective catalytic reduction (SCR) system without conventional mixing elements was developed. The aim was to obtain a high degree of urea decomposition, and uniform ammonia distribution at the inlet to the catalyst, while minimising the liquid film deposition and keeping the compact design. The concept of the design was based on creating high turbulences and elongating the flow paths of the droplets. The design was verified through a series of numerical simulations based on the Reynolds-averaged Navier–Stokes (RANS) approach and a discrete droplet model (DDM) spray representation. The analysis included various operating conditions as well as subcooled and superheated sprays. A uniform ammonia distribution was achieved regardless of the operating points and spray properties. Additionally, in the case of the flash-boiling injection, a further reduction of the wall film was observed.
FUNDING
The project leading to this application has received funding from the National Centre for Research and Development (NCBiR), grant no. MAZOWSZE/0101/19-00, programme Ścieżka dla Mazowsza, project budget: 9 880 490.25 PLN.
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