Remember Me
Or use your Academic/Social account:


Or use your Academic/Social account:


You have just completed your registration at OpenAire.

Before you can login to the site, you will need to activate your account. An e-mail will be sent to you with the proper instructions.


Please note that this site is currently undergoing Beta testing.
Any new content you create is not guaranteed to be present to the final version of the site upon release.

Thank you for your patience,
OpenAire Dev Team.

Close This Message


Verify Password:
Verify E-mail:
*All Fields Are Required.
Please Verify You Are Human:
fbtwitterlinkedinvimeoflicker grey 14rssslideshare1
Georghiades, G.A.
Languages: English
Types: Doctoral thesis
Subjects: TA
This research work presents series of investigations into the structural, dynamic and aeroelastic behaviour of composite wings. The study begins with a literature review where the development of aeroelastic tailoring and specific applications of the technology are discussed in detail. A critique of methods for the determination of cross-sectional rigidity properties follows for beams constructed of laminated and thin-walled materials. Chordwise stiffness is shown to be an important parameter that must be considered as it has a significant effect on the amount of bending-torsion coupling present in a beam and, as a consequence, on the value of torsional rigidity. The free vibration characteristics of such beams are then examined using the dynamic stiffness matrix method. Natural frequencies and mode shapes of various beams are studied using the fibre angle, (3, and the bending-torsion coupling which is measured (in this study) by the non-dimensional parameter 'If, as design variables. The results show that 'If has only a marginal effect on the natural frequencies of composite beams (wings) but can significantly modify the mode shapes of such beams. It can be used to decouple modes which are geometrically (inertially) coupled in the same way as mass balancing but without a weight penalty. It can also be used to abate the unfavourable coupling introduced by sweep angle. Classical flutter and divergence of swept and unswept uniform cantilever wings are investigated using laminated flat beams (plates) and thin-walled beams of rectangular and biconvex cross-sections. Various parameters, such as, the fibre angle, (3, the coupling parameter, 'If, the angle of sweep, A, the static unbalance, xu, and the non-dimensional ratio of the fundamental (uncoupled) bending to fundamental torsional frequency, ffih/ffiu, are varied and their subsequent effects on aeroelastic stability are investigated. The importance of torsional rigidity GJ on the flutter of composite wings is shown to be substantial in contrast with 'If, which is generally the most important parameter to be considered when the objective is that of increasing the divergence speed. Modal interchanges in the free vibration and flutter of laminated composite wings are shown to be primarily responsible for behaviour not experienced with metallic wings, in particular the effect of wash-in and wash-out on flutter. The most intriguing features of these investigations, however, are those which show that models adequate for the analysis of composite wings may be based on two parameters, the frequency ratio ffih/ffiu and the coupling parameter If/. Some results are confirmed by independent optimisation studies. Finally, a preliminary investigation is carried out into the flutter suppression and gust alleviation of a laminated composite wing by the use of active controls. The results show that by using an active control in an optimum trailing edge position the gust response of a wing can be significantly alleviated without compromising the already optimised flutter speed by the use of aeroelastic tailoring
  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

    • 1.29 Wallace, M. M., and Bert, C. W., "Transfer Matrix Analysis of Dynamic Response of Composite-Material Structural Elements with Material Damping," Shock and Vibration Bulletin 50, Part 3, Sept. 1980.
    • 1.30 Hodges, D. H., and Dowell, E. H., "Nonlinear Equations of Motion for the Elastic Bending and Torsion of Twisted Nonuniform Blades," NASA TN D-7818, 1974.
    • 1.31 Panda, B., and Chopra, I., "Dynamics of Composite Rotor Blades in Forward Flight," Vertica, Vol. 11, (1/2), 1987.
    • 1.32 Banerjee, J. R., and Williams, F. W., "Coupled Bending-Torsional Dynamic Stiffness Matrix of an Axially Loaded Timoshenko Beam Element," International Journal of Solids and Structures, Vol. 31, 1994, pp. 749-762.
    • 1.33 Nissim, E., "Flutter Suppression Using Active Controls Based on the Concept of Aerodynamic Energy," NASA TN D-6199, Sept. 1971.
    • 1.34 Nissim, E., Caspi, A., and Lottati, I., "Application of the Aerodynamic Energy Concept to Flutter Suppression and Gust Alleviation by Use of Active Controls, NASA TN D8212, June 1976.
    • 1.35 Suzuki, S., and Yonezawa, S., "Simultaneous Structure/Control Design Optimization of a Wing Structure with a Gust Alleviation System," Journal of Aircraft, Vol. 30, 1993, pp. 268-274.
    • 1.36 Layton, J. B., "Aeroservoelastic Tailoring for Gust Response of a Typical Section Aeroelastic Model," Proceedings of the 36th AIAAI SMEI ASEC/ AHS / ASC Structures, Structural Dynamics, and Materials Conference, AIM Paper 95-1192, 1995, pp. 306-313.
    • 1.37 Banerjee, J. R., and William, F. W., "Vibration of Composite Beams - An Exact Method Using Symbolic Computation," Journal of Aircraft, Vol. 32., 1995, pp. 636-642.
    • 1.38 Wittrick, W. H., and Williams, F. W., "A General Algorithm for Computing Natural Frequencies of Elastic Structures," Quarterly Journal of Mechanics and Applied Mathematics, Vol. 24, 1971, pp. 263-284.
    • 1.39 Davies, D. E., "Theoretical Determination of Subsonic Oscillatory Airforce Coefficients," ARC Rand M 3804, May 1976.
    • 1.40 Vanderplaats, G. N., "ADS-A Fortran Synthesis," NASA CP-177985, Sept. 1985.
    • 2.10 Fletcher, R., and Powell, M. J. D., "A Rapidly Convergent Descent Method for Minimisation," The Compo Journal, Vol. 6, 1963, pp. 163-168.
    • 2.6 2.7 2.8 2.9 2.14 2.15 2.12 Young, D., "Vibration of Rectangular Plates by the Ritz Method," Journal of Applied Mechanics, Vol. 17, 1950, pp. 448-453.
    • 2.13 Barton, M. V., "Vibration of Rectangular and Skew Cantilever Plates Representing Idealised Missile Fins," Defence Research Laboratory, University of Texas, Austin, Rept. 222, Dec. 1949.
    • 2.16 Ashton, J. E., and Waddoups, M. E., "Analysis of Anisotropic Plates," Journal of Composite Materials, Vol. 3, 1969, pp. 148-165.
    • 2.20 Krone, N. J. Jr., "Divergence Elimination with Advanced Composites," Ph.D. Thesis, University of Maryland, College Park, MD, Dec. 1974.
    • 2.21 Krone, N. J. Jr., "Divergence Elimination with Advanced Composites," AIAA Paper 75-39511, 1975.
    • 2.22 Krone, N. J. Jr., "Forward Swept Wing Flight Demonstrator," AIAA Paper 80-1882, 1980.
    • 2.23 Tsai, S. W., and Hahn, H. T., Introduction to Composite Materials, Technomic, Westport, CT, 1980.
    • 2.24 Jones, R. M., Mechanics of Composite Materials, Scripta Book Company, Washington, D.C., 1975.
    • 2.25 Datoo, H. M., Mechanics of Fibrous Composites, Elsevier Applied Science, England, 1991.
    • 2.26 Shirk, M. H., and Griffin, K. E., "The Role of Aeroelasticity in Aircraft Design with Advanced Filamentary Composite Materials," Proceedings of the 2nd Conference on Fibrous Composites in Flight Vehicle Design, AFFDL-TR-74- 103, 1974, pp. 405-438.
    • 2.28 Schmit, L. A., "Structural Synthesis-Its Genesis and Development," AIM Journal, Vol. 19, 1981, pp. 1249-1263.
    • 2.29 Ashley, H., "On Making Things the Best-Aeronautical Uses of Optimisation," Journal of Aircraft, Vol. 19, 1982, pp. 5-28.
    • 2.30 Lansing, W., Lerner, E., and Taylor, R. F., "Applications of Structural Optimisation for Strength and Aeroelastic Design Requirements," AGARD-R-664, Sept. 1977.
    • 2.31 Waddoups, M. E., Smith, C. B., and McMickle, R. W., "Composite Wing Aeroelastic Response Study," AFFDL-TR-71-24, Dec. 1972.
    • 2.32 Waddoups, M. E., McCullers, L. A., and Naberhaus, J. D., "Composite Wing for Transonic Improvement, Vol. II, Advanced Analysis Evaluation," AFFDL-TR-71-24, Nov. 1971.
    • 2.33 Forsch, H., "Advanced Design Composite Aircraft (ADCA) Study," AFFDL-TR-76-97, Vol. I, Nov. 1976.
    • 2.34 Naberhaus, J. D., and Waddoups, M. E., "Dynamic Characteristics of Advanced Filamentary Composite Structures, Vol. III - Demonstration Component Program," AFFDL-TR-73-111, Sept. 1974.
    • 2.35 Lynch, R. W., Rogers, W. A., and Braymen, W. W., "Aeroelastic Tailoring of Advanced Composite Structures for Military Aircraft, Volume I-General Study," AFFDL-TR-76-100, April 1977.
    • 2.36 Rogers, W. A., Braymen, W. W., Murphy, A. C., Graham, D. H., and Love, M. H., "Validation of Aeroelastic Tailoring by Static Aeroelastic and Flutter Tests," AFWAL-TR-81-3160, Sept. 1982.
    • 2.37 Rogers, W. A., Braymen, W. W., and Shirk, M. H., "Design, Analysis and Model Tests of an Aeroelastically Tailored Lifting Surface," AIAA Paper 81-1673,1981.
    • 2.38 Braymen, W. W., Rogers, W. A., and Shirk, M. H., "Wind Tunnel Test and Aerodynamic Analysis of Three Aeroelastically Tailored Wings," presented at the 13th Congress of the International Council of the Aeronautical Sciences and AIAA Aircraft Systems and Technology Conference, ICAS-82-5.7.3, Aug. 1982.
    • 2.40 Lockenhauer, J. L., and Layton, G. P., "RPRV Research Focus on HiMAT," Astronautics &Aeronautics, Vol. 14, 1976, pp. 36-41.
    • 2.42 Brown, L. E. Jr., Price, M A., and Genyrich, P. B., "Aeroelastically Tailored Wing Design," Proceedings of Evolution of Aircraft Wing Design Symposium, Dayton, Ohio, 1980, pp. 141-146.
    • 2.43 Lokos, W., "HiMAT Aeroelastic Analysis," Research and Technology Annual Report 1983, NASA TM-85865, Nov. 1983.
    • 2.44 Hertz, T. J., Shirk, M. H., Ricketts, R. H., and Weisshaar, T. A., "On the Track of Practical Forward-Swept Wings," Astronautics & Aeronautics, Vol. 20, 1982, pp.40-52.
    • 2.45 Wilkinson, K., and Rauch, F., "Predicted and Measured Divergence Speeds of an Advanced Composite Forward Swept Wing Model," AFWAL-TR-80-3059, July 1980.
    • 2.46 Ellis, J. W., Dobbs, S. K., and Miller, G. D., "Structural Design and Wind Tunnel Testing of a Forward Swept Fighter Wing," AFWAL-TR-80-3073, July 1980.
    • 2.47 Gimmestad, D., "An Aeroelastic Optimisation Procedure for Composite High Aspect Ratio Wings," AIAA Paper 79-0726, 1979.
    • 2.48 Gimmestad, D., "Aeroelastic Tailoring of a Composite Winglet for KC-135," Proceedings of the 22nd Structures, Structural Dynamics and Materials Conference, 1981, pp. 373-376.
    • 2.49 Triplett, W. E., "Aeroelastic Tailoring Studies in Fighter Aircraft Design," Proceedings of the 20th Structures, Structural Dynamics and Materials Conference, 1979, pp. 72-78.
    • 2.50 Triplett, W. E., "Aeroelastic Tailoring of a Forward Swept Wing and Comparisons with Three Equivalent Aft Swept Wings," Proceedings of the 21st AIAAlASMEIASCEIAHS Structures, Structural Dynamics and Materials Conference, 1980, pp. 754-760.
    • 2.51 Sensburg, 0., Becker, J., Lusebrink, H., and Weiss, F. "Gust Load Alleviation on Airbus A-300," presented at 13th Congress of the Aeronautical Sciences, 1982.
    • 2.52 Schweiger, J., Sensburg, 0., and Berns, H. J., "Aeroelastic Problems and Structural Design of a Tailless CFC-Sailplane," presented at the Second International Symposium of Aeroelasticity and Structural Dynamics, Aachen, FRG,1985.
    • 2.53 Shirk, M. H., Hertz, T. J., and Weisshaar, T. A., "Aeroelastic Tailoring - Theory, Practice, and Promise," Journal of Aircraft, Vol. 23, 1986. (Reply by Lerner, E. in response to AFWALIFIBR survey letter, March 8, 1983.) 2.54 Austin, F., Hadcock, R., Hutchings, D., Sharp, D., Tang, S., and Waters, C., "Aeroelastic Tailoring of Advanced Composite Lifting Surfaces in Preliminary Design," Proceedings of the AIAAlASMEISAE 17th Structures, Structural Dynamics and Materials Conference, 1976, pp. 69-79.
    • 2.55 Asceni, L., and et aI., "A Structural Weight Estimation Programme (SWEEP) for Aircraft," ASD/XR 74-10, June 1974.
    • 2.56 Dodd, A. J., and et aI., "Aeroelastic Design Optimisation Program," Journal of Aircraft, Vol. 27, 1990, pp. 1028-1036.
    • 2.59 Butler, R, Lillico, M., Banerjee, J. R, and Guo, S., "Optimum Design of High Aspect Ratio Wings Subject to Aeroelastic Constraints," Proceedings of the 36th AIAAlASMEIASCEIAHSIASC Structures, Structural Dynamics and Materials Conference, AIAA Paper 95-1223, 1995, pp. 558-566.
    • 2.60 Butler, R, and Banerjee, J. R, "Optimum Design of Bending-Torsion Coupled Beams with Frequency or Aeroelastic Constraints," Computers and Structures, Vol. 60, 1996, pp. 715-724.
    • 2.61 2.62 Weisshaar, T. A., "Forward Swept Wing Static Aeroelasticity," AFFDL-TR-79- 3087, June 1979.
    • Weisshaar, T. A., "The Influence of Aeroelasticity on Swept Composite Wings," AFWAL-TR-80-3137, Nov. 1980.
    • 2.63 Lerner, E., and Markowitz, J., "An Efficient Structural Resizing Procedure for Meeting Static Aeroelastic Design Objectives," Journal of Aircraft, Vol. 16, 1979, pp.65-71.
    • 2.64 Sherrer, V. C., Hertz, T. J., and Shirk, M. H., "Wind Tunnel Demonstration of Aeroelastic Tailoring Applied. to Forward Swept Wings," Journal of Aircraft, Vol. 18, 1981, pp. 976-983.
    • 2.65 Schneider, G., Godel, H., and Sensburg, 0., "Structural Optimisation of Advanced Aircraft Structures," presented at the 12th Congress of the International Council of the Aeronautical Sciences, 1980.
    • 2.75 Weisshaar, T A., and Foist, B. L., "Aeroelastic Tailoring of Aircraft Subject to Body Freedom Flutter," AFWAL-TR-83-3137, Nov. 1983.
    • 2.76 Chen, G. S., and Dugundji, J., "Experimental Aeroelastic Behaviour of Forward-Swept Graphite/Epoxy Wings with Rigid-Body Freedom," Journal of Aircraft, Vol. 24, 1987, pp. 454-462.
    • 2.78 McCullers, L. A., Naberhaus, J. D., and Bensinger, C. T, "Dynamic Characteristics of Advanced Filamentary Composite Structures, Volume I-Test Specimen Program," AFFDL-TR-73-111, Sept. 1974.
    • 2.83 Rehfield, L. W., Atilgan, A. R., and Hodges, D. H., "Nonclassical Behaviour of Thin-Walled Composite Beams with Closed Cross Sections," Journal of the American Helicopter Society, Vol. 35, 1988, pp. 42-50,.
    • 2.84 Smith, E. C., and Chopra, I., "Formulation and Evaluation of an Analytical Model for Composite Box-Beams," Journal of the American Helicopter Society, Vol. 36, 1991, pp. 23-35.
    • 2.86 Song, 0., and Librescu, L., "Free Vibration and Aeroelastic Divergence of Aircraft Wings Modelled as Composite Thin-Walled Beams," Proceedings of the 32nd AIAAlASMEIASCEIAHSIASC Structures, Structural Dynamics and Materials Conference, AIAA Paper91-1187, 1991, pp. 2128-2136.
    • 2.87 Librescu, L., and Simovich, J., "General Formulation for the Aeroelastic Divergence of Composite Swept-Forward Wing Structures," Journal of Aircraft, Vol. 25, 1988, pp. 364-371.
    • 2.88 Librescu, L., and Khdeir, A. A., "Aeroelastic Divergence of Swept-Forward Composite Wings Including Warping Restraint Effect," AIAA Journal, Vol. 26, 1988, pp. 1373-1377.
    • 2.89 Librescu, L., and Thangjitham, S, "Analytical Studies on Static Aeroelastic Behaviour of Forward-Swept Composite Wing Structures," Journal of Aircraft, Vol. 28,1991, pp. 151-157.
    • 2.90 Librescu, L., and Song, 0., "On the Static Aeroelastic Tailoring of Composite Aircraft Swept Wings Modelled as Thin-Walled Beam Structures," Composite Engineering, Vol. 2, 1992, pp. 497-512.
    • 2.91 Cesnik, C. E. S., Hodges, D. H., and Patil, M. J., "Aeroelastic Analysis of Composite Wings," Proceedings of the 37th AIAAlASMEIASCEIAHS IASC Structures, Structural Dynamics and Materials Conference, AIAA Paper 96-1444,1996, pp. 1113-1123.
    • 2.92 Chattopadhyay, A, Zhang, S., and Ratneshwar, J., "Structural and Aeroelastic Analysis of Composite Wing Box Sections Using a Higher-Order Laminate Theory," Proceedings of the 37th AIAAlASMEIASCEIAHSIASC Structures, Structural Dynamics and Materials Conference, AIAA Paper 96-1567, 1996, pp. 2185-2198.
    • 3.10 Mansfield, E. H., "The Stiffness of a Two-Cell Anisotropic Tube," Aeronautical Quarterly, Vol. 32, 1981, pp. 338-353.
    • 3.14 Hong, C. H., and Chopra, I., "Aeroelastic Stability of a Composite Blade," Journal of the American Helicopter Society, Vol. 30,1985, pp. 57-67.
    • 3.15 Hong, C. H., and Chopra, I., "Aeroelastic Stability Analysis of a Composite Bearingless Rotor Blade," Journal of the American Helicopter Society, Vol. 31, 1986 , pp. 29-35.
    • 3.16 Hodges, D. H., and Dowell, E. H., "Nonlinear Equations of Motions for the Elastic Bending and Torsion of Twisted Nonuniform Blades," NASA TN D-7818, Dec. 1974.
    • 3.17 Chandra, R., Stemple, A. D., and Chopra, I., "Thin-Walled Composite Beams Under Bending, Torsional, and Extensional Loads," Journal of Aircraft, Vol. 27, July 1990, pp. 619-626.
    • 3.18 Rehfield, L. W., and Atilgan, A. R., "Shear Centre and Elastic Axis and their Usefulness for Composite Thin-Walled Beams," Proceedings of the American Society for Composites, Fourth Technical Conference, 1989, pp. 179-188.
    • 7.28 Guo, S., Cheung, W. C., Banerjee, J. R, and Butler, R, "Gust Alleviation and Flutter Suppression of an Optimized Composite Wing With Active Control," Proceedings of the International Forum on Aeroelasticity and Structural Dynamics, 1995, pp. 41.1-41.9.
  • No related research data.
  • No similar publications.

Share - Bookmark

Download from

Cite this article