Issue 50

N. Boychenko et alii, Frattura ed Integrità Strutturale, 50 (2019) 54-67; DOI: 10.3221/IGF-ESIS.50.07 54 Characterization of the stress-strain state in a gas turbine engine compressor disc taking into account damage accumulation Natalia Boychenko, Ivan Ishtyryakov Institute of Power Engineering and Advanced Technologies, FRC Kazan Scientific Center, Russian Academy of Sciences, Russia nataboi@ya.ru , ivan_200999@mail.ru A BSTRACT . A stress-strain state analysis of a gas turbine engine compressor disc was conducted with consideration to the accumulation of damages under various loading conditions in the temperature range. Characterization of constraint effects was performed using the local stress triaxiality h, T Z -factor and I n -factors for various crack sizes and different operation conditions. The distributions of elastic, plastic and creep stress intensity factors were determined by numerical calculation. Results for several crack front positions, temperature values and disc rotation angular velocity were obtained. The differences in the behaviour of elastic and nonlinear fracture resistance parameters were observed on the basis of loading conditions, crack geometry and temperature. Nonlinear stress intensity factors are preferred as the fracture resistance parameters of materials and structures. K EYWORDS . Compressor disc; Creep; Damage; Surface flaw; Plastic stress intensity factor; Creep stress intensity factor. Citation: Boychenko N., Ishtyryakov I., Parametric study of stress-strain state in gas turbine engine compressor disc taking into account damage accumulation, Frattura ed Integrità Strutturale, 50 (2019) 54-67. Received: 28.05.2019 Accepted: 07.07.2019 Published: 01.10.2019 Copyright: © 2019 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. I NTRODUCTION as turbine engines (GTE) are the main power plants in modern aviation. Many types of engines in land and marine engineering are based on GTEs. GTEs are operated under extremely high temperatures and loads for long periods of time. The temperature ranges from -60°C to +1700°C, air pressure can reach 300 MPa, and gas flow rate exceeds the sonic velocity. The main loads are derived from centrifugal forces on the rotating parts of the rotor; a rotation frequency reaches 5000 1/s, and the circumferential speed is –450 m/s. High-strength materials, efficient technological processes and advanced design solutions are used to implement highly reliable parameters. Titanium alloys and stainless steels are often used for highly loaded rotor components, and heat-resistant nickel-based alloys are used for high-temperature turbine components [1, 2]. When in operation, the discs subjected to centrifugal and thermal loads are the most loaded part of the rotors. The compressor disc has various concentrators in the form of grooves, holes, mating surfaces and recesses, etc. In some cases, stresses near concentrators may exceed the yield strength, and plastic stains will occur [3, 4]. G