PSI - Issue 18

V.N. Shlyannikov et al. / Procedia Structural Integrity 18 (2019) 322–329 Author name / Structural Integrity Procedia 00 (2019) 000–000

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represented in Fig. 8c. In addition, based on obtained experimental data and functional relations it is possible to calibrate and verify modern crack growth rate and life-time prediction model.

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Fig. 8. Crack lengths versus fatigue life for both imitation models (a), through-thickness crack sizes (b) and aspect ratio (c) versus fatigue life for imitation model II. 6. Conclusions In this study in order to assess the residual lifetime for cracked aircraft GTE compressor disc two configurations of imitation models were designed on the base of full-size 3D finite element analysis. It is demonstrated that the biaxially loaded imitation model II most accurately reproduced the state of the critical zone of the compressor disk at operation. The fracture surface of imitation model II was analyzed carefully and functional relations between crack sizes, aspect ratio and number of cycles was determined. This information can be very useful for verification of modern crack growth rate and life-time prediction models. The proposed method of imitation modeling for assessing the lifetime of GTE compressor disks has considerable practical importance. References Stepanov N.V., Shkanov I.N., Omel’chenko V.V., Reznik B.G., 1985. Evaluation of stress state and damage sensitivity equivalence of rotating discs in testing on multiaxial electrohydraulic stand. Soviet Aeronautics 28, 2, 120-123. Shlyannikov V.N., Iltchenko B.V., Stepanov N.V., 2001. Fracture analysis of turbine disks and computational–experimental background of the operational decisions. Eng. Failure Analysis 8, 461–475. Ilchenko B.V., Yarullin R.R., Zakharov A.P., Gizzatullin R.Z., 2012. Residual life prediction of power steam turbine disk with fixed operating time. Proceedings of 19th European Conference on Fracture, 1-8. Shlyannikov V.N., Yarullin R.R., Zakharov A.P., 2014. Fatigue of steam turbine blades with damage on the leading edge. Procedia Materials Science 3, 1792-1797. Shlyannikov V.N., 2003. Elastic-Plastic Mixed-Mode Fracture Criteria and Parameters. Springer Verlag: Berlin. Yarullin R.R., Zakharov A.P., Ishtyryakov I.S., 2018. Nonlinear fracture resistance parameters for cracked aircraft GTE compressor disk. Procedia Structural Integity 13, 902-907. Shaniavski A.A., 2003. Tolerance fatigue failures of aircraft components. Synergetics in engineering applications. In: Monography, Ufa, pp. 803 Shlyannikov V.N., Zakharov A.P., 2017. Generalization of mixed mode crack behaviour by the plastic stress intensity factor. Theoret. Appl. Fract. Mech. 91, 52-65. Slyannikov V.N., Yarullin R.R., Ishtyryakov I.S., 2015. Surface crack growth in cylindrical hollow specimen subject to tension and torsion. Frattura ed Integrita Structurale, 33, 335-344. Yarullin R.R., Ishtyryakov I.S., 2016. Fatigue Surface Crack Growth in Aluminum Alloys under Different Temperatures. Procedia Engineering, 160, 199-206. Shlyannikov V.N., Yarullin R.R., Ishtyryakov I.S., 2018. Effect of temperature on the growth of fatigue surface cracks in aluminum alloys. Theoret. Appl. Fract. Mech., 96, 758-767.