|Journal||Journal of Mechanical Engineering – Problemy Mashynobuduvannia|
|Publisher||Anatolii Pidhornyi Institute for Mechanical Engineering Problems
of National Academy of Science of Ukraine
|ISSN||2709-2984 (Print), 2709-2992 (Online)|
|Issue||Vol. 26, no. 1, 2023 (March)|
|Cited by||J. of Mech. Eng., 2023, vol. 26, no. 1, pp. 23-28|
Mykhailo M. Hrebennikov, National Aerospace University “Kharkiv Aviation Institute” (17, Chkalov str., Kharkov, 61070, Ukraine), e-mail: firstname.lastname@example.org, ORCID: 0000-0001-7648-3027
Oleksandr H. Dibir, National Aerospace University “Kharkiv Aviation Institute” (17, Chkalov str., Kharkov, 61070, Ukraine), e-mail: email@example.com, ORCID: 0000-0002-2366-6353
Anatolii O. Kyrpikin, National Aerospace University “Kharkiv Aviation Institute” (17, Chkalov str., Kharkov, 61070, Ukraine), e-mail: firstname.lastname@example.org, ORCID: 0000-0001-8883-0663
Mykola I. Pekelnyi, National Aerospace University “Kharkiv Aviation Institute” (17, Chkalov str., Kharkov, 61070, Ukraine), e-mail: email@example.com, ORCID: 0000-0003-0989-2546
Problem of predicting the residual service life of airplanes and helicopters is highly relevant for flight safety. In this paper, on the basis of the conducted research on the change of mechanical characteristics during materials fatigue accumulation, it is proposed to control the service life by changing the dissipative characteristics. In case of fatigue damage, the accumulative logarithmic decrement of oscillation damping δ increases to the limit maximum value δm, which corresponds to the critical length of the main fatigue crack, which leads to failure. The limit value δm can be set depending on the amount of energy spent on the development of the main fatigue crack, taking into account the dangerous part of the consumed energy. With the accumulation of fatigue damage, the growth of logarithmic decrement occurs at the expense of energy expenditure for the growth of fatigue cracks and internal friction. This is taken into account by the coefficient α, which allows to allocate a dangerous part of the energy that goes into the development of a main fatigue crack. The problem of durability prediction consists of two stages. At first, it is needed to determine δm for the critical crack length. Then, based on the two values of logarithmic decrement at the corresponding load cycles, the number of cycles to failure – to the critical length of the crack – is predicted by the Peris formula.
Keywords: service life, logarithmic decrement, energy expended to destruction, “dangerous” part of the dissipated energy, critical crack length
Full text: Download in PDF
- Troshchenko, V. T. (1971). Ustalost i neuprugost materialov [Fatigue and inelasticity of materials]. Kyiv: Naukova dumka, 268 p. (in Russian).
- Troshchenko, V. T. & Sosnovskiy, L. A. (1987). Soprotivleniye ustalosti metallov i splavov [Fatigue resistance of metals and alloys]. Kyiv: Naukova dumka, 345 p. (in Russian).
- Bulanov, V. V., Kirpikin, A. A., & Suslova, A. G. (1990). Voprosy metodiki prognozirovaniya ostatochnogo resursa konstruktsii [Questions of the methodology for predicting the residual life of a structure]. Prochnost konstruktsiy letatelnykh apparatov [The strength of aircraft structures]: A collection of scientific papers of the Kharkov Aviation Institute, iss. 9, pp. 62–67 (in Russian).
- Bulanov, V. V. & Kirpikin, A. A. (1978). Ob izmenenii fiziko-mekhanicheskikh kharakteristik kompozitsionnykh materialov v protsesse nakopleniya ustalostnykh povrezhdeniy [On the change in the physical and mechanical characteristics of composite materials in the process of accumulation of fatigue damage]. Prochnost konstruktsiy letatelnykh apparatov [The strength of aircraft structures]: A collection of scientific papers of the Kharkov Aviation Institute, iss. 5, pp. 103–106 (in Russian).
- Dibir, A. G., Kirpikin, A. A., & Pekelnyy, N. I. (2008). Approksimatsiya izmeneniya dempfiruyushchikh kharakteristik v protsesse tsiklicheskikh nagruzheniy [Approximation of changes in damping characteristics during cyclic loading]. Otkrytyye informatsionnyye kompyuternyye integrirovannyye tekhnologii [Open information computer integrated technologies]: A collection of scientific papers of the National Aerospace University “Kharkov Aviation Institute”, iss. 38, pp. 88–91 (in Russian).
Received 27 February 2023
Published 30 March 2023