Comparative analysis impulse deformation of aircraft structure elements made of aluminum alloy and composite material

Аuthors

Ryabov A. A.^1*, Romanov V. I.^1**, Maslov E. E.^1***, Strelets D. Y.^2****, Kornev A. V., Ivanov A. I.^*****

1. Sarov Engineering Center, Science and technology park "Sarov", 3, Parkovaya str., Satis, Nizhny Novgorod region, 607328, Russia
2. ,

*e-mail: alex.ryabov@saec.ru
**e-mail: romanov@saec.ru
***e-mail: emaslov@saec.ru
****e-mail: dstrel@okb.sukhoi.org
*****e-mail: okb@okb.sukhoi.org

Abstract

The necessity to increase weight effectiveness of new aviation structures encourages permanent structures modification and development implementing new materials, including composites. Some elements of these airplane structures can be subjected to impulsive loading. Thus, the investigations of dynamic deformation of shells and plates made of composite materials loaded by the impulse pressure are important. As long as the great majority of structures was made in the past of aluminum alloys, it is rather interesting to compare their deformations with those of new stuctures made of composite materials under the same loading to identify the differences and advantages.

The goal of the presented article is numerical and experimental investigations of two plates made of aluminum and composite materials, loaded by equal impulse pressure with maximum amplitude of 6-7 Bar order and 0.3-0.4 ms duration. The composite structure is made of three layers: two outer plates of fiber- reinforced polymer, linked by honeycomb stuff.

We realized numerical simulation is performed on the basis of explicit integration schemes of the equations of motion in time domain and finite element sampling in space in LS-DYNA application software package. Eight-node of Sollid type and four-node finite elements of Shell type are used for sampling. The problem is solved in the Lagrangian formulation. We used Chang- Chang orthotropiс model with possible brittle fracture for composite material. Тhe accuracy of numerical solution is confirmed by the precision of calculation data and experimental results.

Comparative analysis shows that numerical and eхpеrimеntal сurvеs of deformations in several sеlесted points are close to each other. Aluminum and сomposite platеs of diffеrent sizеs are deformed by thе samе dynamiс lоad up to maximum levеls of dеformations lеss than 0.2%. Numеriсal and eхperimental rеsults show that aftеr impulsе loading removal thе platеs keep on their oscillatory motion with the lowest fundamental frequencies. In the еxperimеnts thе period of osсillation damping is about 180-200 ms for aluminum platе and about 40-50 ms for сompositе plate. The three-layer compositе plate demonstrates four times higher damping effect compared to aluminum plate. From the above said we can conclude that numerical calculations of dynamic deformation of composite plate based on Chang-Chang orthotropiс model allow obtaining acceptable results. Further improvement of modeling quality can be achieved by more detailed description of honeycomb stuff.

Keywords:

composite materials, dynamic deformation, finite elements method

References

1. Obraztsov I.F., Vasilev V.V., Bunakov V.A. Optimalnoe armirovanie obolochek vrashcheniya iz kompozitsionnykh materialov (Optimum reinforcing of rotational shells made of composite materials), Moscow, Mashinostroenie, 1977, 144 p.

2. Vanin G.A., Semenyuk N.P., Emelyanov R.F. Ustoichivost obolochek iz armirovannykh materialov (Stability of shells made of reinforced materials), Kiev, Naukova dumka, 1978, 212 p.

3. Bolotin V.V., Novichkov Yu.N. Mekhanika mnogosloinykh konstruktsii (Mechanics of multilayered structures), Moscow, Mashinostroenie, 1980, 375 p.

4. Alfutov N.A., Zinovev P.A., Popov B.G. Raschet mnogosloinykh plastin i obolochek (Calculation of multilayered plates and shells), Moscow, Mashinostroenie, 1984, 264 p.

5. Dudchenko A.A. Prochnost i proektirovanie elementov aviatsionnykh konstruktsii iz kompozitsionnogo materiala (Durability and design of elements of aviation structures made of composite material), Moscow, MAI, 2007, 200 p.

6. Abrosimov N.A., Bazhenov V.G. Nelineinye zadachi dinamiki kompozitnykh konstruktsii (Nonlinear problems of dynamics of composite designs), N. Novgorod, NNGU, 2002, 391 p.

7. Abrosimov N.A. Mekhanika kompozitnykh materialov, 1999, vol. 35, no. 6, pp. 757-776.

8. Abrosimov N.A., Bazhenov V.G., Elesin A.V. Izvestiya Rossiiskoi akademii nauk. Mekhanika tverdogo tela, 2000, no. 2, pp. 181-189.

9. Belytschko T., Lin I.J, Tsay C.-S. Explicit Algorithm for the Nonlinear Dynamics of Shells. — Computer Methods of Applied Mechanics and Engineering, 42, 1983, pp. 225- 251.

10. Vasidzu K. Variatsionnye metody v teorii uprugosti i plastichnosti (Variation methods in the theory of elasticity and plasticity), Moscow, Mir, 1987, 542 p.

11. Sedov L.I. Mekhanika sploshnoi sredy (Continuum mechanics), Moscow, Nauka, 1970, vol. 1 — 492 p., vol. 2 — 568 p.

12. Hallquist John O. LS-DYNA Theory Manual, Livermore Software Technology Corporation, CA, USA, March 2006, 608 p.

13. Programmnyi kompleks trekhmernogo modelirovaniya protsessov nestatsionarnogo nelineinogo deformirovaniya LS- DYNA. Versiya 971. Revision 7600.398. Livermore Software Technology Corporation, Ca, USA, www.lstc.com, 2009.

14. Ananev I.V. Spravochnik po raschetu sobstvennykh kolebanii uprugikh system (Reference book on calculation of natural oscillationы of elastic systems), Moscow, Gostekhizdat, 1946, 224 p.