Theoretical and experimental determination of the boundary conditions influence on gas turbine blade vibration charaсteristics

Mykhaylo Tkach, Sergey Kulishov, Vitalii Polischuk, Yurii Halynkin, Arkadіі Proskurin, Vladimir Kluchnyk

Abstract


A description of the stand based on a digital speckle interferometer with a diffuse reference wave and separated branches is given, which allows determining the natural frequencies and vibration modes of objects in real time. In the frequency range 100...4000 Hz, an experimental study of the vibration characteristics of a turbine rotor blade of a gas turbine engine was carried out, with rigid fastening of the blade fir tree part, which was achieved by fixing the blade in the lock and then fixing it in the clamping device. In the frequency range from 100 to 4000 Hz, 9 blade vibration modes were identified. The object of the study is the turbine rotor blade of a gas turbine engine with a height along the trailing edge of 288 mm and a chord in the middle section of 88.5 mm. A solid-state geometric model of a rotor blade based on a faceted body obtained from 3D scanning has been created. Concerning the frequency range 100...4000 Hz, using the ANSYS Workbench software package, a series of calculations of the resonant frequencies of the blade by the finite element method was carried out. Many vibration modes have been obtained, and the data obtained from experiments and calculations have been compared. The analysis of the spectrum of the natural vibration frequencies of the blade showed that the root-mean-square value of the deviations between the results obtained is 5.5% for the same modes. To verify the software calculation, the values of the resonance frequencies were recalculated using a three-dimensional model of the blade fixed in the lock. To determine the influence of the boundary conditions for fixing a gas turbine blade on its vibration characteristics, a series of calculations of the resonance frequencies and vibration modes of the blade model with cutting off a part of the blade at different heights was carried out. It is shown that cutting off the fir tree part of the blade root when modeling the boundary conditions of fixing makes it possible to simplify the calculation process by simplifying the geometry of the three-dimensional model of the blade under study, with a minimum loss of calculation accuracy.

Keywords


speckle interferometry; GTE blades; finite element method; resonance frequencies; vibration modes

Full Text:

PDF

References


Vorob'ev, Yu. S. Kolebaniya lopatochnogo apparata turbomashin [Vibrations of the blade apparatus of turbomachines]. Kyiv, Nauk. dumka Publ., 1988. 224 p.

Vorob'ev, Yu. S., Shul'zhenko, N. G. Issledovanie kolebanii sistem elementov turboagregatov [Investigation of oscillations of systems of elements of turbine units]. Kyiv, Nauk. dumka Publ., 1978. 152 p.

Vorobiov, Yu. S., Chugay, A. M., Rao, J. S. and other. Vibration stress localization in turbomachinery blading. VETOMAC VII International Conference On Vibration Engineering And Technology of Machinery. Gdansk, Poland, 2012, pp. 324-331.

Zaidel'man, R. L. Nadezhnost' lopatochnogo apparata parovykh turbin [Reliability of the blade apparatus of steam turbines]. Moscow, Energiya Publ., 1988. 224 p.

Levin, A. V. Prochnost' i vibratsiya lopatok i diskov parovykh turbin [Strength and vibration of blades and disks of steam turbines]. Moscow, Mashinostroenie Publ., 1981. 710 p.

Kostyuk, A. G. Dynamics and strength of tur-bines. Moscow, Mashinostroenie Publ., 1982. 486 p.

Yakabe, T., Xiao, F., Iwamoto, K., et. al. Six-Port Based Wave-Correlator with Application to Beam Direction Finding. IEEE Trans. In-strum. Meas. Apr. No. 2, Vol. 50, 2001, pp. 377-380.

Sosunov, V. A., Chepkin, V. M. The theory, calculation and de-sign of the aircraft engines. Moscow Energetic Institute Press, 2003. 526 p.

Vest, Ch. Golograficheskaya interferometriya [Holographic interferometry]. Moscow, Mir Publ., 1982. 504 p.

Ostrovsky, Yu. I., Shchepinov, V. V., Yakovlev, V. V. Holographic interference methods for measuring deformations. Moscow, Nauka Press, 1988. 336 p.

Kresis, Th. Handbook of holographic interferometry. Optical and Digital Methods Weinheim. WILEY-VCH Verlag GmbH & Co. KGaA Publishing house, 2005. 542 p.

Jones, R., Wykes, C. Holographic and speckle interferometry. A discussion of the theory, practise and application of the technique. Cambridge, Cambridge University Press, 1989. 353 p.

Tkach, M. R., Zolotoy, Yu. H., Dovhan, D. V., Zhuk I. Yu. Issledovanie form sobstvennykh kolebanii elementov GTD metodom golograficheskoi interferometrii v real'nom vremeni [Investigation of the gas turbine engines vibration modes using the method of holographic interferometry in real time]. Aviacijno-kosmicna tehnika i tehnologia – Aerospace technic and technology, 2011, no. 8(85), pp. 51-56.

Bystrov, N. D., Zhuzhukin, A. I. Speckle interferometry in the investigation of large-size turbine engine structures vibration. Procedia engineering, 2017, no. 176, pp. 471-475. DOI: 10.1016/j.proeng.2017.02.346.

Shorr, B. F. Osnovy teorii zakruchennykh lopatok s nepryamoi os'yu [Fundamentals of the theory of twisted blades with an indirect axis]. Prochnost' i dinamika aviatsionnykh dvigatelei, 1976, no. 3, pp. 188-223.

Vorob'ev, Yu. S., Sapelkina, Z. V. Kolebaniya konsol'nykh zakruchennykh sterzhnei nesimmetrichnogo poperechnogo secheniya [Oscillations of cantilever twisted rods of asymmetric cross section]. Dinamika i prochnost' mashin, 1973, no. 18, pp. 62-69.

Vorob'ev, Yu. S., Shorr, B. F. Teoriya zakruchennykh sterzhnei [Theory of twisted rods]. Kiev, Naukova dumka Publ., 1983. 188 p.

Birger, I. A. Variatsionnye metody v stroitel'noi mekhanike turbomashin [Variational methods in the structural mechanics of turbomachines]. Moscow, Mashinostroenie Publ., 1979. 107 p.

Borishanskii, K. N. Osobennosti kolebanii lopatok s bandazhnymi polkami [Oscillations of blades with shroud]. Problemy prochnosti, 1974, no. 9, pp. 97-102.

Vorob'ev, Yu. S., Gontarovskii, P. P. Ispol'zovanie variatsionnykh metodov pri vibratsionnykh raschetakh rabochikh lopatok i vozdushnykh vintov [The use of variational methods in vibration calculations of rotor blades and propellers]. Prikladnaya mekhanika, 1981, no. 7, pp. 71-76.

Zenkevich, O. Metod konechnykh elementov v tekhnike [Finite element method in engineering]. Moscow, Mir Publ., 1975. 542 p.

Emissions and lifetime estimation modeling of industrial gas turbines. M. Sc. Progress Review. Cranfield University, C. Samaras, UK, 2009, pp. 30-35.

Krishnakanth, P. V., Narasa-Raju, G. Structural and thermal analysis of gas turbine blade by using FEM. International Journal of Scientific Research Engineering and Technology, 2013, no. 2(2), pp. 60-65.

Mrinaline, M. Steady state structural analysis of single crystal turbine blade. International Journal of Engineering Research and Technology, 2016, no. 5(10), pp. 382–384. DOI: 10.17577/ijertv5is100314.

Baqersad, J., Niezrecki, C., Avitabile, P. Predicting full-field dynamic strain on a three-bladed wind turbine using three dimensional point tracking and expansion techniques. Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems, 2014, pp. 56-62. DOI: 10.1117/12.2046106.

Pyhalov, E., Milov, A. Static and dynamic analysis of the turbine rotors assemblies. Irkutsk, Irkutsk Technical University Press. 2007. 120 p.

Morgun, S. The blades constructions finite elements models development. Bulletin of the National Technical University «KhPI». Ser. New Solutions in Modern Technologies, 2016, no. 42 (1214), pp. 86-91. DOI: 10.20998/2413-4295.2016.42.14.

Tkach, M. Improving the Noise Immunity of the Measuring and Computing Coherent-Optical Vibrodiagnostic Complex. Lecture Notes in Networks and Systems, Springer Cham, 2020, vol. 188, pp. 277–289. DOI: 10.1007/978-3-030-66717-7_23.

Tkach, M. R., Zolotoi, Yu. G., Zhuk, I. Yu., Galynkin, Yu. N., Proskurin, A. Yu., Klyuchnik, V. S. Eksperimental'noe opredelenie vibratsionnykh kharakteristik rabochikh lopatok turbin po-mekhoustoichivym tsifrovym spekl-interferometrom [Experimental Determination of Vibration Characteristics of Turbine Blades with Noise-Immune Digital Speckle Interferometer]. Aviacijno-kosmicna tehnika i tehnologia – Aerospace technic and technology, 2021, no. 4 (174), pp. 52-61. DOI: https://doi.org/10.32620/aktt.2021.4sup2.07.

Tkach, M. R., Zhuk, I. Yu., Dovhan', D. V., Zolotyy, Yu. H. Sposib vyznachennya chastot i form rezonansnykh kolyvan' lopatok hazoturbinnoho dvyhuna metodom spekl-interferometriyi [A method for determining the frequencies and shapes of resonant coliving blades of a gas turbine engine using the speckle-interferometry method]. Patent UA, №. 103068, 2015.

Tkach, M., Morhun, S., Zolotoy, Y., Zhuk I. Modal analysis of the axial compressor blade: advanced time-dependent electronic interferometry and finite element method. Int. J. Turbo Jet-Eng, 2021. DOI: 10.1515/tjj-2020-0014.

Tkach, M. R., Kulishov, S. B., Polishchuk, V. A., Klyuchnik, V. S., Zolotoi, Yu. G., Zhuk, I. Yu., Proskurin, A. Yu., Galynkin, Yu. N. Eksperimental'no-raschetnoe opredelenie mekhanicheskikh svoistv materiala rabochikh lopatok GTD [Experimental and computational determination of the mechanical properties of the material of rotor blades]. Aviacijno-kosmicna tehnika i tehnologia – Aerospace technic and technology, 2021, no. 4 (173), pp. 83-92. DOI: 10.32620/aktt.2021.4sup1.12.




DOI: https://doi.org/10.32620/aktt.2022.4sup2.08