Numerical investigation of the back pressure influence on urea-water-solution mixing performance in close coupled SCR system

• Autorzy: Rogóż R. , Bachanek J. , Boruc Ł. , Teodorczyk A.

Identyfikatory

DOI

10.5604/01.3001.0012.4355

• Języki publikacji: EN

Abstrakty

EN

The upcoming Euro 6d emission standard puts more even stringent requirements for diesel engine cars, especially in the case of nitrogen oxides (NOx) emission. The most widely used technique to meet tight standards is Selective Catalytic Reduction (SCR) with urea-water-solution (UWS) injection. One of the crucial factors is even ammonia distribution at the catalyst inlet; hence, very often product development is focused around this issue. The product development is supported by both experimental and numerical work. The common approach to measure cross section ammonia distribution on the SCR is using sampling system at catalyst outlet. Very often exhaust layout is opened just after the SCR catalyst, cutting off the rest part for instance tailpipe or Clean-up Catalyst. Therefore, a backpressure at SCR outlet resulting from the downstream part is also eliminated. This could significantly affect flow parameters as the density changes, thus ammonia distribution and wall film deposition may vary as well. Within this work, the influence of the backpressure at SCR outlet on the ammonia distribution and wall wetting was numerically investigated. The simulations were run under various boundary conditions for the Close Coupled SCR architecture. It was shown that depending on the operating point the boundary pressure affects both factors on the different level.

Słowa kluczowe

EN

SCR; urea water solution; uniformity; CFD; back pressure

• Wydawca: Łukasiewicz Research Network - Institute of Aviation ; European Science Society of Powertrain and Transport KONES Poland ; Wydawnictwo Instytutu Technicznego Wojsk Lotniczych
• Czasopismo: Journal of KONES
• Rocznik: 2018
• Tom: Vol. 25, No. 3
• Strony: 377--383
• Opis fizyczny: Bibliogr. 12 poz., rys.

Twórcy

autor

Rogóż R.

• Warsaw University of Technology Faculty of Power and Aeronautical Engineering Institute of Heat Engineering Nowowiejska Street 21/25, 00-665 Warsaw, Poland tel.: [phone]

autor

Bachanek J.

• Warsaw University of Technology Faculty of Power and Aeronautical Engineering Institute of Heat Engineering Nowowiejska Street 21/25, 00-665 Warsaw, Poland tel.: [phone]

autor

Boruc Ł.

• Warsaw University of Technology Faculty of Power and Aeronautical Engineering Institute of Heat Engineering Nowowiejska Street 21/25, 00-665 Warsaw, Poland tel.: [phone]

autor

Teodorczyk A.

• Warsaw University of Technology Faculty of Power and Aeronautical Engineering Institute of Heat Engineering Nowowiejska Street 21/25, 00-665 Warsaw, Poland tel.: [phone]

Bibliografia

• [1] Birkhold, F., Meingast, U., Wassermann, P., Deutschmann, O., Modeling and simulation of the injection of urea-water-solution for automotive SCR DeNOx-systems, Appl. Catal. B Environ., Vol. 70, No. 1-4, pp. 119-127, 2007.
• [2] Brack, W., et al., Kinetic modeling of urea decomposition based on systematic thermo-gravimetric analyses of urea and its most important by-products, Chem. Eng. Sci., Vol. 106, pp. 1-8, 2014.
• [3] Choi, C., Sung, Y., Choi, G. M., Kim, D. J., Numerical analysis of NOx reduction for compact design in marine urea-SCR system, Int. J. Nav. Archit. Ocean Eng., Vol. 7, pp. 1020-1033, 2015.
• [4] Gehrlein, J., Lang, A., Palmer, G., Optimization of SCR systems by integration of mixture elements, MTZ Worldw., Vol. 70, No. 3, pp. 18-22, 2009.
• [5] Grout, S., Blaisot, J. B., Pajot, K., Osbat, G., Experimental investigation on the injection of an urea-water solution in hot air stream for the SCR application: Evaporation and spray/wall interaction, Fuel, Vol. 106, pp. 166-177, 2013.
• [6] Guan, B., Zhan, R., Lin, H., Huang, Z., Review of state of the art technologies of selective catalytic reduction of NOx from diesel engine exhaust, Appl. Therm. Eng., Vol. 66, No. 1-2, pp. 395-414, 2014.
• [7] Koebel, M., Elsener, M., Kleemann, M., Urea-SCR: a promising technique to reduce NOx emissions from automotive diesel engines, Catal. Today, Vol. 59, No. 3, pp. 335-345, 2000.
• [8] Lee, C., Numerical and experimental investigation of evaporation and mixture uniformity of urea – water solution in selective catalytic reduction system, Transp. Res. Part D, 2017.
• [9] Prabhu, S, S., Nayak, N. S., Kapilan, N., Hindasageri, V., An experimental and numerical study on effects of exhaust gas temperature and flow rate on deposit formation in Urea-Selective Catalytic Reduction (SCR) system of modern automobiles, Appl. Therm. Eng., Vol. 111, pp. 1211-1231, 2017.
• [10] Praveena, V., Martin, M. L. J., A review on various after treatment techniques to reduce NOx emissions in a CI engine, J. Energy Inst., pp. 1-17, June, 2017.
• [11] Tan, L., Feng, P., Yang, S., Guo, Y., Liu, S., Li, Z., CFD studies on effects of SCR mixers on the performance of urea conversion and mixing of the reducing agent, Chem. Eng. Process. Process Intensif., Vol. 123, pp. 82-88, January, 2018.
• [12] European Union, 2007. Regulation (EC) No 715/2007

Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2018).