A RESEARCH ON INFLUENCE OF NOZZLE GEOMETRY ON THERMODYNAMIC AND FLUID DYNAMIC EXHAUST PROPERTIES OF A SMALL-SCALE JET ENGINE
Abstract
The purpose of this study is to evaluate the effectiveness of nozzle profiling of a small turbojet engine with an ejector as a method of reducing the thermal signature of an aircraft by CFD modeling of the original and modified engine nozzle ducts and by analyzing the resulting flow parameters.
The main task of the research is to conduct a qualitative analysis of the intensification of mixing of ejector and nozzle flows in a small turbojet engine using CFD simulation of a modified design in order to reduce the thermal signature of the engine.
During the simulation, a number of factors were identified that influence the studied effects of interaction between the ejector flow and the nozzle: aircraft speed, aerodynamic drag of the ejector, parameters characterizing flow turbulence in the mixing zone, etc. The results of the simulation include contours of dynamic pressure, temperature, flow velocity, and all the main thermal and fluid dynamic parameters of the flow in the three-dimensional calculation domain.
It has been shown that profiling the nozzle of a small turbojet engine in combination with the use of an ejector allows the formation of vortex flows that intensify the mixing of the secondary flow of the ejector with the primary flow of the nozzle and can be used to improve heat transfer and, according to similar studies, reduce the thermal signature of engine exhaust.
The described method will be further improved for a detailed quantitative analysis of the influence of the geometric profile parameters of the ejector nozzle on the mixing intensification and thermal visibility of a small turbojet engine.
References
2. R. Schmidt, A. Hupfer (2021-08-16). Design and numerical simulation of ejector nozzles for very small turbojet engines. CEAS Aeronautical Journal, 12(4), 18 pages. https://doi.org/10.1007/s13272-021-00537-3.
3. Y. Shan, J.-z. Zhang, and G.-p. Huang (2014-11-19). Experimental and Numerical Studies on Lobed Ejector Exhaust System for Micro Turbojet Engine. Aerospace. https://doi.org/10.1080/19942060.2011.11015358.
4. Makarchuk, B. O., Ponomarenko, S. M. A research on influence of exhaust shape on thermodynamic and fluid dynamic exhaust properties of a small-scale jet engine. Thermophysics and Thermal Power Engineering, 2025, vol. 47(1), 89-99. ISSN 2663-7243 (online). [Digital source] https://ihe.nas.gov.ua/index.php/journal/article/view/619
5. JetCat, P180NX Gas Turbine Engine specifications (2026-02-03). [Digital source] https://www.jetcat.de/en/productdetails/produkte/jetcat/produkte/Eingestellte%20Produkte%20Zubehoer/p180_nx.
6. K. I. Komarov, B. O. Makarchuk, S. M. Ponomarenko. Influence of nozzle geometry on exhaust flow dynamics of a small-scale turbojet. Thesis of XXIII Ukrainian scientific conference “Theoretical and applied problems of physics, mathematics and computing” (14 – 17 May 2025, Kyiv). P. 112-115. ISBN 978-966-990-053-1 .
7. Rao, Arvind G. (2011). Infrared Signature Modeling and Analysis of Aircraft Plume. International Journal of Turbo Jet Engines, 28, 187-197. https://doi.org/10.1515/tjj.2011.023 .
8. R. E. Ball. The Fundamentals of Aircraft Combat Survivability: Analysis and Design, 2nd Edition // 2003. https://doi.org/10.2514/4.862519 .
9. Dix J. et al. Infra-red signature reduction study on a small-scale jet engine. The Aeronautical Journal. 2005. Т. vol. 109. № no. 1092. С. p.p. 83-88. https://doi.org/10.1017/S0001924000000580 .
10. Choi S. M., Jang H. S., Park H. H. Infrared signal of the lobed mixer with external air mixing // The Aeronautical Journal. 2021. Т. vol. 125. № no. 1291. С. p.p. 1501-1518. https://doi.org/10.1017/aer.2021.28 .
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