TY - CONF
T1 - Nonlinear aeroelastic effects in damaged composite aerospace structures
AU - Bauchau, O. A.
AU - Zhang, H. C.
AU - Loewy, R. G.
AU - Atluri, S. N.
N1 - Funding Information:
This work was supported by the Air Force Office of Scientific Research under Grant F49620-95-1-0241. Major Brian Sander is the contract monitor.
Publisher Copyright:
© 1997, American Institute of Aeronautics and Astronautics, Inc.
PY - 1997
Y1 - 1997
N2 - This paper focuses on the effect of matrix microcracking on the aeroelastic behavior of elastically tailored wings. Matrix microcracking is shown to give rise to nonlinear material constitutive laws in the presence of non uniformly distributed crack densities. Such matrix damage is found to have little effect on flutter speed. The aeroelastic response of wings with matrix microcracking is qualitatively similar to that of an undamaged wing. However, the amplitude of the aeroelastic oscillations can be significantly higher for wings with microcracking. Root vibratory stresses could double in such beams, possibly resulting in significant fatigue life degradation. The aeroelastic response to a sharp edged gust for wings with one lay-up configuration was found qualitatively similar for wings without and with microcracking, though significantly higher vibration levels were observed in the microcracked beam. For another lay-up, a sharp qualitative difference exists for the damaged wing: large amplitude, undamped aeroelastic oscillations typical of a limit cycle behavior were observed. This limit cycle bevavior seems to disappear at lower air speeds.
AB - This paper focuses on the effect of matrix microcracking on the aeroelastic behavior of elastically tailored wings. Matrix microcracking is shown to give rise to nonlinear material constitutive laws in the presence of non uniformly distributed crack densities. Such matrix damage is found to have little effect on flutter speed. The aeroelastic response of wings with matrix microcracking is qualitatively similar to that of an undamaged wing. However, the amplitude of the aeroelastic oscillations can be significantly higher for wings with microcracking. Root vibratory stresses could double in such beams, possibly resulting in significant fatigue life degradation. The aeroelastic response to a sharp edged gust for wings with one lay-up configuration was found qualitatively similar for wings without and with microcracking, though significantly higher vibration levels were observed in the microcracked beam. For another lay-up, a sharp qualitative difference exists for the damaged wing: large amplitude, undamped aeroelastic oscillations typical of a limit cycle behavior were observed. This limit cycle bevavior seems to disappear at lower air speeds.
UR - http://www.scopus.com/inward/record.url?scp=84983122792&partnerID=8YFLogxK
M3 - Paper
AN - SCOPUS:84983122792
T2 - 35th Aerospace Sciences Meeting and Exhibit, 1997
Y2 - 6 January 1997 through 9 January 1997
ER -