Morozov N.A., Vlasov Y.L., Gavrilov A.A. OPTIMIZATION OF PARAMETERS OF COMPOSITE COVERINGS DRY COMPARTMENTS OF AIRCRAFT BY MEANS OF NASTRANThe researches devoted to minimization of mass of aircraft will never stop being the actual. Decrease in weight allows to lower costs of production of the aircraft, to reduce the dynamic loadings arising when transporting and in the course of its flight and also to reduce amount of fuel, necessary for flight. The purpose of receiving the covering providing the greatest coefficient of a stock of the general stability and the maximum durability of a compartment on condition of minimization of its weight was set. Researches were conducted by modeling of the intense deformed condition of coverings by means of a method of final elements in Nastran. For research the layered model consisting of variously reinforced layers of composite material of the set thickness was used. As a result of calculation on durability and stability of various coverings it was established that optimum schemes of laying of four-layer coverings are the schemes having the inside layers (the closest to a longitudinal axis of a compartment) reinforced under angles and the external layer reinforced at an angle. Lack of distinction in stability and durability of coverings in case of mutual change of places of the layers reinforced under angles provides possibility of replacement of these two layers with one orthotropic layer. When modeling dry compartments of aircraft the preference needs to be given to the four-layer coverings having the scheme of an arrangement of layers (45, –45, 0, 90). Influence of change of quantity of four-layer packages of layers of a covering on its durability and stability was investigated, thus thickness of a covering was accepted by the invariable. It was established that distributions of tension and the maximum tension arising in coverings are identical, and the coefficient of a stock of the general stability increases with increase in number of packages of layers. And, the essential increase in coefficient of a stock of stability occurs only when using two packages of layers therefore when modeling coverings from bigger quantity of packages of layers it is recommended to use technical and economic calculations.Key words: composite material, covering, durability, stability, layer, optimization.
1 . Abrosimov, N. A. Optimal design of laminated composite shells of revolution irregular structures under impulse and shock stress/ N. A. Abrosimov, V. G. Bazhenov, V. P. Stolov // Mechanics of composite materials. — 1990. — No. 6. — Pp. 1087-1093
2. Bakulin, V. N. Methods of optimal design and analysis of composite structures. In 2 t. T. 1. Optimal design of composite structures and traditional materials / V. N. Bakulin, E. L. Gusev, V. G. Markov. — M.: Fizmatlit, 2008. — 256 p.
3. Balevicius, R. Shape optimization of laminated orthotropic PLA-stinate structures / R. Balevicius // Mechanics of composite materials. — 1993. — No. 4. — Pp. 537-546
4. Bunakov, V. A. Optimal design of structures made of composite materials / V. A. Bunakov, V. B. Markin. — Barnaul: Altai state technical. Univ. I. I. Polzunov, 1994. — 57 p.
5. Vasiliev, V. V. fundamentals of design and manufacturing design of aircraft structures made of composite materials: a manual / V. V. Vasiliev, A. A. Dobryakov, A. A. Dudchenko and others — M.: MAI, 1985. — 218 p.
6. Dudchenko, A. A. Optimal design of aircraft structures made of composite materials: textbook / A. A. Dudchenko. — Moscow: MAI, 2002. — 84 p.
7. Zinoviev, P. A. Optimal design of composite materials / P. A. Zinoviev, A. A. Shipkov. — M.: Izd-vo MGTU im. N. E. Bauman, 2006. — 103 p.
8. Kolpakov, A. G. Design of fibrous composites for data deformation-strength characteristics / A. G. Kolpakov // Journal of applied mechanics and technical. physics. — 1995. — Vol. 36, No. 5. — Pp. 113-123
9. Lizin, V. T. Design of thin-walled structures: a textbook for University students — 3rd ed./ V. T. Lizin, V. A. Pyatkin. — M.: Mashinostroenie, 1994. — 384 p.
10. Morozov, N. A. The influence of the geometric characteristics of the stringers on the stability of stiffened cylindrical sheathing aircraft/ N. A. Moro-zov, S. D. Ezenin // University complex as a regional center of education, science and culture: materials of all-Russian scientific conference (with international participation). — Orenburg: OSU, 2015. — Pp. 77-81
11. Morozov, N. A. Study of the influence of the angle of reinforcement of composite materials on the stability of the sheathing elements of aircraft/ N. A. Morozov // School — seminar of young scientists and specialists in the field of computer integration of production: materials. Orenburg LLC EPC "University", 2015 — Pp. 91-95
12. Morozov, N. A. Optimization of the parameters of sheathing dry compartments missiles made of composite materials/ N. And. Morozov, Vlasov Y. L., Gavrilov A. A. // Progressive technologies in transport systems: proceedings of the twelfth international scientific and practical conference — Orenburg: OSU, 2015. — Pp. 282-286
13. Mutz A. Optimization of laminated composite structures with randomly distributed mechanical properties / A. Mutz // Mechanics of composite materials. 2005. — Vol. 41, No. 6. — Pp. 753-760
14. Nemirovsky, Y. V. Rational design of reinforced-structures / Y. V. Nemirovsky, A. P. Jankowski — Novosibirsk: Nauka, 2002. — 488 p.
15. Obolensky, P. E. The strength of the aircraft and their units: a textbook for students of aviation specialties / E. P. Obolensky, B. I. Sakharov, V. A. Sibiryakov; ed. by I. F. Obraztsov. — Moscow: Mashinostroenie, 1995. — 504 p.
16. Potchman, Y. M. Optimization of cylindrical composite shells with regard to critical fashion imperfections / Y. M. Potchman, S. A. Shulga // Mechanics of composite materials. 1998. — Vol. 34, No. 5. — P. 613-620
17. Smerdov A. A. Fundamentals of optimal design of composite structures / A. A. Smerdov. — M.: Izd-vo MGTU im. N. E. Bauman, 2006. — 88 p.
18. Tetere, G.A. Multipurpose optimal design of composite structures / G. A. Tetere, A. F. Kregers // Mechanics of composite materials. — 1996. — Vol. 32, No. 3. — Pp. 363-376
About this article
Authors: Vlasov Yu.L., Morozov N.A., Gavrilov A.A.