NUMERICAL COMPUTATIONS OF EXHAUST GASES JET FROM AIRCRAFT ENGINE UNDER IDLE OPERATIONAL CONDITIONS
Keywords:aircraft engine, exhaust gases jet, air pollution, airport air quality, boundary conditions
Purpose: Currently models for airport air quality are based on the semi-empirical approaches for description of fluid dynamic of exhaust gases jet from aircraft engine and do not take into account an influence of the ground on jet behaviour and the interaction between the jet and the wing trailing vortex system. Eliminating the fluid mechanisms of aircraft wake vortex in models of airport air quality may overestimate the height of buoyancy exhaust gases jet from aircraft engine, underestimate its length and radius of expansion, dispersion characteristics and contaminants concentration values. Evaluation the entrainment and mixing processes of the engine emissions in the plume by using CFD-code is an actual task for airport air quality studies. Methods: Numerical investigation of properties and structure of aircraft engine jets with CFD codes (OpenFOAM) will give a realistic checked material, on the base of which a necessary scientific reasoning of transportation of the contaminants by engine jets. Results: Comparison between OpenFOAM numerical results and semi-empirical jet model calculations (used by complex model PolEmiCa) show that buoyancy effect parameters of exhaust gases decrease twice for wall jet. And the difference between appropriate longitudinal coordinate of buoyancy effect is near to 30%. Discussion: using CFD tool allows to improve an airport air quality analysis by providing more objective and accurate input data for further dispersion modelling.
Graham and D. Raper. "Air Quality in Airport Approaches: Impact of Emissions entrained by Vortices in Aircraft Wakes". Available at: http://www.cate.mmu.ac.uk/documents/Publications/Woct03.pdf. (2003).
K. Schäfer, C. Jahn, P. Sturm, B. Lechner and M. Bacher. "Aircraft Emission Measurements by Remote Sensing Methodologies at Airports". Atmospheric Environment, Vol. 37, pp. 5261-5271. (2003). https://doi.org/10.1016/j.atmosenv.2003.09.002
Chan T.L., Dong G., Leung C.W., Cheung C.S., Hung W.T. Validation of a 2D Pollutant Dispersion Model in an Isolated Street Canyon. - Atmospheric Environment. - 2002. - №36. - P.861-872. https://doi.org/10.1016/S1352-2310(01)00490-3
Harvey, J. K. & Perry, F. J. Flowfield produced by trailing vortices in the vicinity of the ground. - AIAA J. - 1971. - №9 (8) - P.1659-1660. https://doi.org/10.2514/3.6415
Atias, M., Weihs, D. Motion of aircraft trailing vortices near the ground. - J. Aircraft. - 1984. - №21(10). - P.783-786. https://doi.org/10.2514/3.45042
Spalart, P. R., Strelets, M. K., Tra vin, A. K., & Shur, M. L. Modeling the Interaction of a Vortex Pair with the Ground. - Fluid Dynamic. - 2001. - № 36(6). - P.899-908. https://doi.org/10.1023/A:1017958425271
Aloysius Syoginus S., Wrobel Luiz C. ALAQS-CFD Comparison of Buoyant Free and Wall Turbulent Jets// School of Engineering & Design Brunel University. - UK, 2007. - 58 p.
Aloysius Syoginus S., Wrobel Luiz C., Pearce D. ALAQS-Comparison of CFD and Lagrangian Dispersion Methods - Simple Scenario during Take-off // School of Engineering & Design Brunel University. - UK, 2007. - 32 p.
Syoginus S. Aloysius and Luiz C. Wrobel On the Use of Near Field Computational Fluid Dynamics for Improving Airport Related Dispersion Models // Third International Conference On Research In Air Transportation Fairfax, Va, June 1-4 2008, 8 p.
M.R. Davis and H. Winarto. "Jet Diffusion from a Circular Nozzle above a Solid Plane". Journal of Fluid Mechanics. Vol. 101, part 1, pp.201-222. (1980). https://doi.org/10.1017/S0022112080001607
Bradbury L.J.S. The Structure of a Self-Preserving Turbulent Jet. - J. Fluid Mech. - 1965. -№ 23 - P.31-64. https://doi.org/10.1017/S0022112065001222
Forthmann E. Turbulent Jet Expansion. English translation, NACA Technical Memorandum TM-789. - 1936.
Wygnanski, I., Katz, Y., Horev, E. On the Applicability of Various Scaling Laws to the Turbulent Wall Jet". - J. Fluid Mech. - 1992. - Vol. 234 - P. 669-690. https://doi.org/10.1017/S002211209200096X
Wayson R.L., Flemming G.G., Eberhard W., Kim B. Final report: The use of LIDAR to characterize aircraft initial plume characteristics // FAA-AEE-04-01. - 2004. - 35 p.
User Manual of Open Foam. Available at: https://www.openfoam.com/
Synylo K., Zaporozhets O., FröhlichJ., Stiller J. Improvement of Airport Local Air Quality Modeling // Journal of Aircraft. - 2017. - Vol. 54. - № 5. - P. 1750 -1759 (Scopus). https://doi.org/10.2514/1.C033803
Zaporozhets O., Synylo K. PolEmiCa - tool for air pollution and aircraft engine emission assessment in airports // 2-nd World Congress Proc.: "Aviation in XXI Century", Environment Protection Symposium. - 2005. - P. 4.22 -4.28
Emissions and Dispersion Modelling System (EDMS) // Reference Manual. FAA-AEE-01-01. U.S. Department of Transportation Federal Aviation Administration, Washington, D.C. CSSI, Inc., Washington, D.C. - September 2002.
Janicke Consulting, LASPORT version 1.3 Reference Book. - November 2005. - 93 p. https://doi.org/10.1007/978-3-663-11695-0_7