Authors : Alex Ayedun Avwunuketa

Volume/Issue : Volume 10 - 2025, Issue 12 - December

Google Scholar : https://tinyurl.com/2p7j6397

Scribd : https://tinyurl.com/4dky9hj8

DOI : https://doi.org/10.38124/ijisrt/25dec543

Note : A published paper may take 4-5 working days from the publication date to appear in PlumX Metrics, Semantic Scholar, and ResearchGate.

Abstract : Multi-stage axial compressors are essential component of aerospace propulsion system because the structure of the exit flow field of an axial compressor directly influences the performance and stability of an aerospace engine. In this research paper, the numerical simulations of the first 3 stages of a transonic multi-stage axial compressor were carried out to study the characteristics of the exit flow field of the compressor under four operating conditions. The main focus of the research was airflow deflection angle, patterns of radial velocity distribution, and its changes. Also, the influence of the angle of inlets air direction and pressure on the outlet flow system on the unsteady conditions of inlet airflow were considered. The findings show that when rotational speed reaches a level of 68 %, exit flow field of the axial compressor degrades significantly. The operating conditions, the velocity and airflow angle is positively correlated with the rotational speed as the rotational speed decreases. In comparison to the design condition, the peak velocity reduces by 2%, 3.7% and 7%, whereas airflow deflection angle deviations are less than 3°. Under non-uniform inlet conditions, as the airflow angle at inlet reduced by 90° to 70°, the differences in peak and mean exit velocity do not exceed 2 % and the differences in peak and mean airflow deflection angle do not exceed 1 %. A relatively small effect of alteration in a local pressure field on the inlet pressure in a non-uniform environment produces a very significant impact on the local distributions. When inlet pressure is changed between 1 atm and 1.05 atm, the value of the peak velocity changes by 0.98 percent and that of the average velocity by 3 percent. Maximum difference in velocities is 6 %, and average airflow deflection angle has a difference of 0.7 %, but its maximum deviation valued 1.9°. In general, the characteristics of the flow field on the exit of the compressor demonstrate considerable changes under various operating conditions. The flow in the compressors with low rotational velocities will be more unstable, which causes the flow separation and accumulation of fluid with low energy and non-uniform pressure distribution. On the contrary, variable inlet conditions can have a relatively small impact on the whole flow field, with significant local alterations, which can be used in the theoretical basis to optimized design and performance assessment of compressors.

Keywords : Aerodynamics, Axial, Compressor, Flow, Transonic.

References :

1. B.Semlitsch, "Boundary conditions to represent the wave impedance characteristics of axial compressors.," Applied Acoustics, vol. 4, no. 109236, 2023.
2. X. Wang and C. Gu, "Rotor optimization design of a multistage transonic compressor based on entropy loss breakdown analysis," Aerospace Science and Technology, vol. 163, no. 110288, 2025.
3. J. Jiang, B. Liu, Y. Wang and X. Nan, " Numerical Simulation to Three-Dimensional Turbulent Flow in Multistage Axial Compressor Blade Row," Journal of Applied Mechanical, vol. 2, p. 21–25+170, 2007.
4. A. Liu, Y. Ju and Z. C. , "Parallel rotor/stator interaction methods and steady/unsteady flow simulations of multi-row axial compressors," Aerospace Science and Technology, vol. 116, no. 106859, 2021.
5. C. Silva, I. Durán, F. Nicoud and S. Moreau, "Boundary Conditions for the Computation of Thermoacoustic Modes in Combustion Chambers," AAIA Journal, vol. 52, no. 6, p. 1180–1193, 2014.
6. J. Cheng, J. CHen and H. Xiang, "A surface parametric control and global optimization method for axial flow compressor blades," Chinese Journal of Aeronautics, vol. 32, no. 7, pp. 1618-1634, 2019.
7. A. Liu, Y. Ju, C. Zhang and R. Dia, "Parallel steady/unsteady flow simulations of an 8.5-stage axial compressor," Aerospace Science and Technology, vol. 145, no. 108853, 2024.
8. N. Lamarque and T. Poinsot, " Boundary Conditions for Acoustic Eigenmodes Computation in Gas turbine Combustion Chambers," AIAA Journal, vol. 46, p. 2282–2292., 2008.
9. Y. Sun, "The Influence of Inlet Distortion on the Operating Characteristics of Transonic Axial-Flow Compressor.," Harbin Engineering University, Master’s Thesis, Harbin, China,, 2020.
10. L. Zhang, Y. Liu and S. Sun, " Numerical study on the effects of different total temperature inlet distortions on the aerodynamic performance and stability of the centrifugal compressor," Aerospace Science and Technology, vol. 163, no. 110292, 2025.
11. W. Zhang, S. Stapelfeldt and M. Vahdati, "Influence of the inlet distortion on fan stall margin at different rotational speeds," Aerospace Science and Technology, vol. 98, no. 105668, 2020.
12. W. Gong, G. Liu, J. Wang, F. Wang, A. Lin and Z. Wang, "Aerodynamic and thermodynamic analysis of an aero-engine pre-swirl system based on structure design and performance improvement," Aerospace Science and Technology, vol. 23, no. 107466, p. 123, 2022.
13. G. Liu, X. Wang, W. Gong and A. Lin, "Prediction of the sealing flow effect on the temperature drop characteristics of a pre-swirl system in an aero-engine," Applied Thermal Engineering, vol. 189, no. 1167172021, 2021.
14. A. Liu, Y. Ju and C. Zhang, "Parallel rotor/stator interaction methods and steady/unsteady flow simulations of multi-row axial compressors," Aerospace Science and Technology, vol. 116, no. 106859, 2021.
15. J. Jiang, B. Liu, Y. Wang and X. Nan, " Numerical Simulation to Three-Dimensional Turbulent Flow in Multistage Axial Compressor Blade Row," Journal of Applied Mechanical, vol. 2, p. 320–325, 2008.
16. S. Peng, X. Zhang, W. Wang, H. Zhang and X. Li, "Numerical Simulation on Unsteady Flow Mechanism of a 1.5-Stage Axial Transonic Compressor," Journal of Thermal Science, vol. 33, p. 1851–1866, 2024.
17. H. Jia and H. Wu, "Numerical simulation of three-dimensional flow field in transonic compressor rotor.," Aeronautical and Computational Technology , vol. 35, p. 3 94–97, 2005.
18. F. Wang, L. Zhao, L. He and M. Zhang, " Three-Dimensional CFD Flow Field Analysis and Aerodynamic Optimization of a Multi-Stage Axial Compressor.," Therm. Turbine , vol. 41 , p. 215–219, 2012.
19. A. Avwunuketa, J. Enyia and S. Oloruntoba, "Numerical and Thermal Finite Element Analysis (FEA) of Idealized Gas Turbine Engine Blade," International Journal of Aerospace and Mechanical Engineering (IJAME), vol. 7, no. 1, pp. 14 - 18, 2020.
20. L. Zhang, Y. Liu and S. Sun, "Numerical study on effects of total pressure distortion on unsteady effect of impeller-diffuser interactionin centrifugal compressor.," Propuls. Technol. 2025, , p. 1–14, 2025.
21. A. Baretter, B. Godard, P. Joseph, O. Roussette, F. Romanò, R. Barrier and A. Dazin, "Experimental and Numerical Analysis of a Compressor Stage under Flow Distortion," International Journal of Turbomachinery, Propulsion and Power, vol. 6, no. 43, pp. 1-12, 2021.
22. N. Ma, X. Nan, F. Tang, J. Zhang and R. Liu, "Numerical study on evolution mechanism of inlet total temperature distortion in an axi-centrifugal compressor," J. Propulsion Technology , 2024.
23. W. Tian, B. Tu and J. Hu, "Numerical Simulation of Influence of Swirl Distortion and Total Pressure Distortion on Performance and Stability of Booster Stage.," Journal Nav. Aviat. Univ., vol. 40, p. 213–227, 2025.
24. A. Lesser and R. Niehuis, "Transonic Axial Compressors With Total Pressure Inlet Flow Field Distortions," in SME Turbo Expo 2014: Turbine Technical Conference and Exposition, 2014.
25. T. Pan, J. Yan, H. Lu and Q. Li, "Impact of circumferential inlet distortion on different types of stall inceptions in a transonic compressor," Chinese Journal of Aeronautics, vol. 37, no. 11, pp. 107-117, 2024.
26. G. Zhu, X. Liu, B. Yang and M. Song, "A study of influences of inlet total pressure distortions on clearance flow in an axial compressor," Journal of Engineering for Gas Turbines and Power, vol. 143, no. 10, 2021.
27. W. Zhang and M. Vahdati, "A parametric study of the effects of inlet distortion on fan aerodynamic stability," Journal of Turbomachinery, vol. 141, no. 1, 2019.
28. K. Kikuchi, A. Tamura, Y. Matsuo, K. Hirai, H. Kodama and O. Nozaki, " Unsteady three-dimensional analysis of inlet distortion in turbomachinery.," in Proceedings of the 33rd Joint Propulsion Conference and Exhibit, Seattle, WA, USA, 1997.
29. V. Fidalgo, C. Hall and Y. Colin, "A Study of Fan-Distortion Interaction Within the NASA Rotor 67 Transonic Stage," Journal of turbomachinery, vol. 134, no. 5, 2012.
30. P. Sun, G. Feng and D. Kui, " Numerical Simulation of the Impact of Total-pressure Distortion on the Aerodynamic Performance of Small-sized Fans.," Thermal Power Engineering , vol. 21, p. 259–263, 2006.
31. Q. Gao, X. Yang and S. Liu, "Experiment on inlet distortion of high bypass ratio fan and booster," Journal of Aerospace Power , vol. 40, p. 44–52, 2025.
32. W. Wang, T. He, W. Sun, X. Wang, W. He and B. Wang, "Numerical Investigation of Bleed Rate on Performance of Multistage Axial Compressor.," Gas Turbine Technol. , vol. 37, p. 1–10, 2024.
33. X. W. Zhang, Y. P. Ju and C. Zhang, " Performance prediction and IGV-stator adjustment optimization of a multi-stage axial-flow compressor.," J. Eng. Thermophys. , vol. 41, p. 1418–1427, 2020.
34. A. Avwunuketa, B. Bonet, M. Adamu, U. Haruna and O. Fadenipo, "Performance, Characterization and Evaluation of Axial Flow Turbine Engine," International Journal of Advances in Scientific Research and Engineering (IJASRE), vol. 5, no. 10, pp. 124 - 131, 2019.
35. R. Steinke, "Design of 9.271-Pressure-Ratio Five-Stage Core Compressor and Overall Performance for First Three Stages," NASA Technical Paper 2597; National Aeronautics and Space Administration , Cleveland, OH, USA, 1986.
36. D. Jiang, H. Li, C. Liu, Y. Hu, Y. Li, Y. Yan and C. Zhang, "Aerodynamic Characteristics of Typical Operating Conditions and the Impact of Inlet Flow Non-Uniformity in a Multi-Stage Transonic Axial Compressor," Processes , vol. 13, no. 1428, 2025.