A study on the response of high aspect ratio composite wing structures due to gust load

Abstract

The purpose of this study is to acquire the correlation between composite tailoring at symmetric balanced laminate and gust response on high aspect ratio wing. As a flexible structure, the high aspect ratio wing had a susceptibility from dynamic loading. Gust or turbulence load is one of dynamic loading which can have a bad impact on the wing structure. There are many incidents caused by turbulence load, hence to obtain structural response is important. Because gust load is a stiffness problem, one way to handle these effects is to make the airframe more rigid which is not favorable due to the weight penalty in the gross weight of the aircraft. Plies orientations can be an alternative to make structure stiffer without adding structural weight. From this study, plies-orientations at symmetrically laminated composite had been varied starting from 0 to 90 degrees with 5 degrees increment at the skin of the wing. Bending and torsional natural frequencies have changed where changed in play orientation as well as the vibration response from the gust load. The discrete gust cases defined in the EASA requirements are used in this study. The structural response from the gust problem had different characteristics between angle plies laminate, cross-plies laminate, and various plies orientation. As a result of this research that symmetrically balanced laminate composite with fiber direction ±15 or ±75 degrees had a good bending characteristic, nevertheless that direction have the lowest bending stiffness. Further research needs to optimize the plies orientation to design the high aspect ratio wing which has a good aeroelastic response and minimize weight.