Aerospace Technic and Technology

The implementation of the high requirements for modern gas turbine engines depends on the perfection of their components. The reliability of the engine operation is largely determined by the compressor gas-dynamic stability margin. In this paper, a review and analysis of some of the most common approaches to determining the boundary of the compressor gas-dynamic stability region calculation are performed. Based on the analysis, it is shown that the diffuser factor and the equivalent diffuser coefficient are the most suitable for the practice of computational studies at the stage of designing and adjusting the compressor. However, different literary sources present different ranges of the limiting values of these criteria, corresponding to the boundary of gas-dynamic stability, which, in turn, can significantly affect the compressor stability margin. In this regard, it becomes necessary to determine the limiting values of the diffusivity criteria, which can be used both in the design of a compressor and in the construction of a model of a gas turbine engine using the proprietary description of blade machines. To analyze these criteria, we calculated a two-dimensional flow in an axial multistage compressor of a modern by-pass engine using the AxSym software package developed at the Department of Theory of Aircraft Engines of the National Aerospace University "KhAI". A comparison of the calculated data with the results of a physical experiment is carried out. The features of the change in the diffuser factor and the equivalent diffusion ratio depending on the compressor operating mode are established. Dependences which allow approximating the values of these criteria for different rotational speeds are proposed. Recommendations which specify the limiting values of the diffuser factor and the equivalent diffusion ratio for various compressor operating modes are presented.

axial multistage compressor; safe operation area; diffuser factor; equivalent diffusion ratio

Brusilovskij, I. V. Ajerodinamicheskij raschet osevyh ventiljatorov [Aerodynamic calculation of axial fans]. Moscow, Mashinostroenie Publ., 1986. 284 p.

Holshhevnikov, K. V., Emin, O. N., Mitrohin, V. T. Teorija i raschet aviacionnyh lopatochnyh mashin [Theory and calculation of aircraft blades]. Moscow, Mashinostroenie Publ., 1986. 432 p.

Aungier, R. H. Axial-Flow Compressors. New York, ASME Press Publ., 2003. 368 pр.

Templalexis, I., Pilidis, P., Pachidis, V., Kotsiopoulos, P. Development of a 2-D compressor streamline curvature code. Proceedings of ASME Turbo Expo 2006: Turbomachinery Technical Conference and Exposition GT2016 – 57104. Barcelona, 2006. 10 pр.

Liu, Zhiyuan., Luo, Weiwei., Zhao, Qingjun,, Zhao, Wei., Xu, Jianzhong. Preliminary Design and Model Assessment of a Supercritical CO 2 Compressor. Applied Sciences, 2018, vol. 8, iss. 4, article id: 595. 20 p. DOI: 10.3390/app8040595.

Kleppler, J. Technique to predict stage-by-stage, pre-stall compressor performance characteristics using a streamline curvature code with loss and deviation correlations [PhD Thesis]. Tennessee, 1998. 124 p.

Acarer, Sercan., Ozkol, Unver. An extension of the streamline curvature through-flow design method for bypass fans of turbofan engines. Proc IMechE Part G: J Aerospace Engineering, 2017, vol. 231, iss. 2, pp. 1-14. DOI: 10.1177/0954410016636159.

Lieblein, S. Loss and Stall Analysis of Compressor Cascades. J. Basic Engineering, 1959, vol. 81, no. 3, pp. 387-397.

Lieblein, S. Analysis of experimental low-speed loss and stall characteristics of two-dimensional compressor blade cascades. NACA RM E57A28, 1957. 64 р.

Koch, C. C., Smith, L. H. Loss Sources and Magnitudes in Axial-Flow Compressors. J. Eng. Power, 1976, vol. 98, no. 3, pp. 411-424.

Schobeiri, M. Turbomachinery Flow Physics and Dynamic Performance. Berlin, Springer-Verlag Publ., 2005. 522 р.

AI-Daini, A. J. Loss and deviation model for a compressor blade element. Int. J. Heat and Fluid Flow, 1986, vol. 7, no. 1, pp. 69-78.

Swan, W. A Practical Method of Predicting Transonic-Compressor Performance. J. Eng. Power, 1961, vol. 83 no. 3, pp. 322-330.

Lei, V.-M., Spakovszky, S., Greitzer, E. M. A Criterion for Axial Compressor Hub-Corner Stall. J. Turbomachinery, 2008, vol. 130, no. 3. 10 p.

Yamada, Kazutoyo,, Furukawa, Masato., Tamura, Yuki., Saito, Seishiro., Matsuoka, Akinori., Nakayama, Kentaro. Large-Scale Des Analysis of Stall Inception Process in a Multi-Stage Axial Flow Compressor. Proceedings of ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition GT2016 – 57104. Seoul, 2016. 12 p.

Nechaev, Ju. N., Fedorov, R. M. Teorija aviacionnyh gazoturbinnyh dvigatelej [Theory of aircraft gas turbine engines]. Moscow, Mashinostroenija Publ., 1977. 312 p.

Kampsti, N. Ajerodinamika kompressorov [Compressor aerodynamics]. Moscow, Mir Publ., 2000. 688 p.

Boyko, L. G., Kislov, O. V., Pizhankova, N. V. Metod rascheta termogazodi-namicheskih parametrov turboval'nogo GTD na osnove povencovogo opisanija lopatochnyh mashin. Chast' 1. Osnovnye uravnenija [Method for calculating the thermogasdynamic parameters of a turboshaft gas turbine engine based on the princely description of blade machines. Part 1. Basic equations]. Aviacijno-kosmicna tehnika i tehnologia - Aerospace technic and technology, 2018, no 1/145, p. 48-58. DOI: 10.32620/aktt.2018.1.05.

Boyko, L. G., Kovaljov, M. A. Metod raschjota do- i transzvukovogo techenija v osevyh kompressorah i rezul'taty ego aprobacii [Method for calculating sub- and transonic flows in axial compressors and the results of its approbation]. Sovershenstvovanie turboustanovok meto-dami matematicheskogo i fizicheskogo jeksperimen-ta: Tr.mezhd. n.t. konf. [Improvement of turbine plants by methods of mathematical and physical experiment: Proceedings of the international scientific and technical conference]. Khar'kov, 1997, pp. 260-263

Boyko, L. G., Dyomin, A. E. Numerical study of flows in axial compressors of aircraft gas-turbine engines. Eastern-European Journal of Enterprise Technologies, 2018, vol. 4, no. 8(94), p. 40-49. DOI: 10.15587/1729-4061.2018.139445.

Bojko, L. G. Komp'juternaja programma AxSym [AxSym computer program] Registration decision no. 3570, 2017.

Boyko, L. G., Djomin, A. E., Maksimov, Ju. R., Ahtemenko, Ju. F. Regulirovanie mnogostupenchatogo osevogo kompressora na osnove dvumernogo analiza techenija [Control of a multistage axial compressor based on 2D flow analysis]. Trudy XVI Mezhdunarodnoj nauchno-tehnicheskoj konferencii po kompressoro-stroeniju [Proceedings of the XVI International Scientific and Technical Conference on Compressor Engineering]. St. Peterburg, 2014, pp. 318-327.