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Impact of Intake Port Water Injection Timing on Mitigating the Tradeoff between Performance and NOx Emissions for a Naturally Aspired Micro-CHP-Engine
Technical Paper
2019-32-0576
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English
Abstract
Small natural gas cogeneration engines usually operate with lean mixture and late combustion phasing to comply with NOx emission standards, leading to significant losses in engine efficiency. Owing to water evaporation heat and high specific heat capacity of the water vapor, leads the water injection to cooling the combustion chamber charge, which enables earlier combustion phasing, higher compression ratio and thus higher engine efficiency. Therefore, water injection enables mitigating the tradeoff between NOx emissions and engine performance, without loss in engine efficiency. The intake port injection represents, because of the low required injection pressure and the simple injector integration, a cost-effective way to introduce water into the engine. Hence, the purpose of this work is to adapt the intake port water injection timing to the charge mixture flow conditions in the intake port.
For this purpose, a variation of the injection timing was experimentally carried out on the engine test bench. The combustion phasing and the NOx emissions were kept constant. At the same time, the engine power, engine efficiency, temperatures in the intake port and mass flow rates were recorded. To gain a deeper insight into the complex processes in the intake port, such as spray-flow interaction, wallfilm formation and evaporation, 3D CFD simulations were conducted for three selected cases with different injection timings. For the 3D CFD Simulations, the spray model used, was tuned with help of spray pictures, taken on the spray test bed.
Experimental investigations have shown that an injection close to the intake valve opening allows an increase in engine performance at constant NOx emissions without loss of engine efficiency. In fact, early injection allows effective cooling of the intake port mixture and allows part of the injected water to enter the combustion chamber as liquid and to vaporize there. A disadvantage of an injection close to the intake port opening, shown by the 3D CFD simulations, is that the water vapor is distributed homogeneously in the combustion chamber with a slightly higher concentration in the prechamber area, which could lead to a significant slowdown of the combustion speed, if the injected amount of water is increased.
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Beltaifa, Y., Kettner, M., Eilts, P., and Klaissle, M., "Impact of Intake Port Water Injection Timing on Mitigating the Tradeoff between Performance and NOx Emissions for a Naturally Aspired Micro-CHP-Engine," SAE Technical Paper 2019-32-0576, 2020.Data Sets - Support Documents
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References
- Prognose AG , „Potential-und Kosten-Nutzen-Analyse zu den Einsatzmöglichkeiten von Kraft-Wärmekopplung (Umsetzung der EU-Energieeffizienzrichtlinie) sowie Evaluierung der KWKG im Jahr 2014
- Bundesministerium für Wirtschaft und Energie, „Eckpunkte-Papier „Strommarkt“,“, 2015
- Tschalamoff, T., and Sahl, C. , „Saugrohr-Wassereinspritzung an einem Ottogasmotor,“, 6. Dessauer Gasmotorenkonferenz, 2009
- Vaudrey, A. , „Thermodynamics of indirect water injection in internal combustion engines: Analysis of the fresh mixture cooling effect,” International J. of Engine Research, DOI: 10.1177/1468087418766931
- Wu, J., Kang, Z., Deng, J., Wu, Z., et al. , „Numerical Study of Intake Manifold Water Injection on Characteristics of Combustion and Emissions in a Heavy-Duty Natural Gas Engine,“, SAE Technical Paper 2019-01-0562, doi:10.4271/2019-01-0562, 2019
- Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit, “Technische Anleitung zur Reinhaltung der Luft: TA Luft,” 2002
- Pauer, T., Frohnmaier, M., Walther, J., and Schenk, P. , „Optimization of Gasoline Engines by Water Injection,“ 25th Aachen Colloquim Automobile and Engine Technology 2016, At Aachen
- Battistoni, M., Grimaldi, C., Discepoli, G., and Cruccolini, V. , “ Assessment of Port Water Injection Strategies to Control Knock in a GDI Engine through Multi-Cycle CFD Simulations,” SAE Technical Paper 2017-24-0034, 2017, doi:10.4271/2017-24-0034
- Ashgriz, N. , “Handbook od Atomization and Sprays,” DOI 10.1007/978-1-4419-7264-4_12, Springer Science+Business Media, LLC 2011
- Lefebvre, A., and McDonell, V. , “Atomization and Sprays,” ebook, ISBN 9781498736268, 2017
- Heywood, J. , “Internal Combustion Engine Fundamentals,” vol. 1988, McGraw-Hill, ISBN 0-07-028637-X, 1988
- Matsuoka, S., Tasaka, H., and Tsuruta, J. , “The Evaporation of Fuel and Its Effect on Volumetric Efficiency,” JARI technical memorandum no. 2, pp. 17-22, 1971
- Brehm, C., Whitelaw, J., Sassi, L., Vafidis, C. et al. , “ Air and Fuel Characteristics in the Intake Port of a SI Engine,” SAE Technical Paper 1999-01-1491, 1999
- Risk, N., and Lefebvre, A. , “Internal Flow Characteristics of Simplex Swirl Atomizers,” AIAA J. Propul. Power, Vol. 1, No 3, 1985
- AVL List GmbH, “Spray Module: AVL Fire Version v2018”, 2018
- Giffen, E., and Muraszew, A. , “ The Atomization of Liquid Fuels,”, New York: John Wiley & Sons, 1953
- Clark, C., and Dombrowski, N. , “Aerodynamic instability and disintegration of inviscid liquid sheets,” Chem. Eng. Sci., Vol. 18, 1963
- Hung, D., Harrington, D., Gandhi, A., and Markle, L., et al. „Gasoline Fuel Injector spray Measurement and Characterization - A New SAE J2715 Recommended Practice,” SAE Int. J. Fuels Lubr., Volume 1, Issue 1, 2008-01-1068, 2008
- Busch, S., and Miles, P. , “Parametric Study of Injection Rates With Solenoid Injectors in an Injection Quantity and Rate Measuring Device,” Journal of Engineering for Gas Turbines and Power, Copy right 2015 by ASME, Vol. 137/ 101503-1, October 2015
- Seebode, J. , “ Dieselmotorische Einspritzratenformung unter dem Einfluss von Druckmodulation und Nadelsitzdrosselung,“, Ph.D. Thesis, Universität Hannover, 2004
- Mühlbauer, M. , „Modelling wall interactions of high-pressure, hllow cone spray,“, Ph.D. Thesis, Technische Universität Darmstadt, 2009
- Neher, D. , “Miller Cycle and Exhaust Gas Recirculation for a Naturally Aspired Lean-burn Gas Engine,” Ph.D. Thesis, Universidad de Valladolid, 2017