Methodology for predicting the residual resource during depressurization of aircraft


DOI: 10.34759/trd-2022-125-08

Аuthors

Belyaev B. V.*, Lebedev A. S.*

Mlitary spaсe Aсademy named after A.F. Mozhaisky, Saint Petersburg, Russia

*e-mail: vka@mil.ru

Abstract

When determining the flight safety of aircraft, one of the urgent tasks is to diagnose a possible violation of the tightness of compartments during operation. Mechanical damage to sealed compartments of aircraft can occur due to fatigue, wear, thermal load, creep of the material, shock load, elastic deformation, surface fatigue, radiation damage, erosion wear and other causes. Leakproofness tests during the preparation of aircraft for operation are not always able to determine microcracks or other design defects that lead to a violation of the tightness of the device during flight.

The article is devoted to the topical topic of diagnostics of the process of functioning of sealed compartments of aircraft with through microcracks. In the article, expressions are obtained that allow us to describe the patterns of changes in the leakage of the working medium through through cracks, depending on their changing geometry. An algorithm has been developed for constructing patterns of changes in the leakage of the working medium from sealed compartments in the presence of developing through cracks in their shells. Typical patterns of changes in the leakage of the working medium over time through through cracks are given. The results of calculating the time of depressurization of the compartment are presented, depending on the length of the through crack, the degree of its opening, as well as the free volume of the sealed compartment. The results presented in the article make it possible to more correctly diagnose failures of aircraft in flight operation.

In addition, the results obtained make it possible to solve the inverse problem for instrument and habitable compartments of spacecraft. Namely, having the data of telemetric information about the parameters of the gas state (pressure and temperature) inside the compartment and the change of these parameters over time, it becomes possible to diagnose the characteristics of micron densities in the conditions of orbital flight. This, in turn, makes it possible to estimate the time reserve for localization of leaks or to make a decision for an emergency landing of a manned spacecraft.

The proposed technique for diagnosing the tightness of aircraft during flight operation can be used to justify the requirements for sensors and pressure detectors in the hermetic compartments of aircraft and for the parameters of the system of reserve gas reserves. In case of emergency leaks during flight operation, it is possible, using the proposed methodology, to determine the remaining time reserve for eliminating the consequences of an accident, ensuring the safety of crew members or emergency landing on the Ground.

Keywords:

crack, leak, residual life, tightness, diagnostics, operability, sealed compartment

References

  1. Maksimov G.Yu. Teoreticheskie osnovy razrabotki KA (Theoretical foundations of the development of KA), Moscow, Nauka, 1980, 320 p.
  2. Timashev S.V., Lebedev Yu.N., Syrtsov L.A. et al. Osnovy teorii, konstruktsii i ekspluatatsii energeticheskikh i dvigatel’nykh ustanovok kosmicheskikh apparatov s neyadernymi istochnikami energii (Fundamentals of the theory, design and operation of power and propulsion systems of spacecraft with non-nuclear energy sources), Saint Petersburg, VIKKI im. A.F. Mozhaiskogo, 1992, 511 p.
  3. Derevenskikh V.F., Doronin A.P., Lyamin V.A. et al. Tezisy dokladov Mezhdunarodnoi konferentsii «Ekologicheskaya bezopasnost’ na poroge 21 veka», Saint Petersburg, 1999.
  4. Barkova M.E. Trudy MAI, 2014, no. 75. URL: http://trudymai.ru/eng/published.php?ID=35927
  5. Frolov E.S., Minaichev V.E. Vakuumnaya tekhnika: Spravochnik (Vacuum technology: Handbook), Moscow, Mashinostroenie, 1985, 360 p.
  6. Golubev A.I., Kondakov L.A. Uplotneniya i uplotnitel’naya tekhnika: Spravochnik (Seals and sealing equipment: Handbook) Moscow, Mashinostroenie, 1986, 464 p.
  7. Panasyuk V.V. Mekhanika razrusheniya i prochnost’ materialov (Mechanics of destruction and strength of materials), Kiev, Naukova dumka, 1988-1990.
  8. Derevenskikh V.F., Pavutnitskii Yu.V., Lyamin V.A. Nauchnye trudy II Mezhdunarodnogo seminara «Sovremennye problemy prochnosti» im. V.A. Likhacheva, Staraya Russa, 1998, vol. 2, pp. 189-201.
  9. Derevenskikh V.F., Pavutnitskii Yu.V., Lyamin K.A. Nauchnye trudy II Mezhdunarodnogo seminara «Sovremennye problemy prochnosti» im. V.A. Likhacheva, Staraya Russa, 1998, vol. 2, pp. 220-226.
  10. Panasyuk V.V., Andreikiv A.E., Kovchik S.E. Metody otsenki treshchinostoikosti konstruktsionnykh materialov (Methods for assessing the crack resistance of structural materials), Kiev, Naukova dumka, 1977, 277 p.
  11. Troshchenko V.T., Pokrovskii V.V., Prokopenko A.V. Treshchinostoikost’ metallov pri tsiklicheskom nagruzhenii (Crack resistance of metals under cyclic loading), Kiev, Naukova dumka, 1987, 256 p.
  12. Kuznetsov E.B. Leonov S.S. Trudy MAI, 2013, no. 65. URL: http://trudymai.ru/eng/published.php?ID=35927
  13. Endogur A.I., Kravtsov V.A. Trudy MAI, 2013, no. 64. URL: http://trudymai.ru/eng/published.php?ID=36558
  14. Golub V.P., Plashchinskaya A.V. Teoreticheskaya i prikladnaya mekhanika, 2003, no. 38, pp. 91-96.
  15. Antunes F.V. Chegini F.G., Branco R., Camas D. A numerical study of plasticity induced crack closure under plane strain conditions, International Journal of Fatigue, 2015, no. 71, pp. 75-86. URL: https://doi.org/10.1016/j.ijfatigue.2014.03.016
  16. Yates J.R., Zanganeh M., Tomlinson R.A., Brown M.W., Garrido F.A. Crack paths under mixed mode loading, Engineering Fracture Mechanics, 2008, no. 75, pp. 319-330.
  17. Shakirtov M.M., Shabanov A.P., Kornev V.M. Prikladnaya mekhanika i tekhnicheskaya fizika, 2013, vol. 54, no. 2, pp. 163-170.
  18. Shakirtov M.M. Trudy MAI, 2016, no. 89. URL: http://trudymai.ru/eng/published.php?ID=75559
  19. Shabanov A.P. Prikladnaya mekhanika i tekhnicheskaya fizika, 2005, vol. 46, no. 6, pp. 108-115.
  20. Khokhlov A.V. Trudy MAI, 2016, no. 91. URL: http://trudymai.ru/eng/published.php?ID=75559
  21. Kutovoi V.P., Shabanov A.P., Shakirtov M.M. Izvestiya Transsiba, 2013, no. 1 (13), p. 89-94.
  22. Shabanov A.P. Problemy mashinostroeniya i nadezhnosti mashin, 2010, no. 5, pp. 40-47.
  23. Kotsan’da S. Ustalostnoe rastreskivanie metallov (Fatigue cracking of metals), Moscow, Metallurgiya, 1990, 623 p.
  24. Troshchenko V.T., Sosnovskii L.A. Soprotivlenie ustalosti metallov i splavov (Fatigue resistance of metals and alloys), Kiev, Naukova dumka, 1987, 175 p.
  25. Golovin C.A., Pushkar A. Mikroplastichnost’ i ustalost’ metallov (Microplasticity and fatigue of metals), Moscow, Metallurgiya, 1980, 240 p.
  26. Belyaev B.V., Golikov I.O., Dobrolyubov A.N., Lebedev A.S. Trudy MAI, 2020, no. 114. URL: https://trudymai.ru/eng/published.php?ID=118918. DOI: 10.34759/trd-2020-114-09

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