This paper presents an analytical study on optimization of a laminated compositewing structure for achieving a maximum flutter speed and a minimum weightwithout strength penalty. The investigation is carried out within the range ofincompressible airflow and subsonic speed. In the first stage of theoptimization, attention has been paid mainly to the effect on flutter speed ofthe bending, torsion and, more importantly, the bending-torsional couplingrigidity, which is usually associated with asymmetric laminate lay-up. The studyhas shown that the torsional rigidity plays a dominant role, while the couplingrigidity has also quite a significant effect on the flutter speed. In the secondstage of the optimization, attention has been paid to the weight and laminatestrength of the wing structure, which is affected by the variation in laminatelay-up in the first stage. Results from a thin-walled wing box made of laminatedcomposite material show that up to 18 per cent increase in flutter speed and 13per cent reduction in weight can be achieved without compromising the strength.The investigation has shown that a careful choice of initial lay-up and designvariables leads to a desirable bending, torsional and coupling rigidities, withthe provision of an efficient approach when achieving a maximum flutter speedwith a minimum mass of a composite wing.
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