Optimal design of laminate composite isogrid with dynamically reconfigurable quantum PSO

Optimal design of stiffened laminated composite cylinder of symmetric and balanced layup with isogrid form stiffeners is investigated and presented. The isogrid stiffened cylinder is subjected to uniform compressive load. In the optimization for the maximum buckling load, the panel skin laminate stacking sequence and stiffener configuration are chosen as design variables. A smeared model is employed in the buckling analysis of the stiffened composite cylinder. A new variant of particle swarm intelligence algorithm, using multiple swarms, built with quantum and dynamically reconfigurable features is developed and employed in the present investigations. The optimization is carried out using the proposed multi swarm based quantum particle swarm optimisation (PSO) algorithm, taking into consideration of the ply contiguous constraint. An optimal layup of the skin and stiffener configuration has also been obtained by using the proposed dynamic quantum PSO algorithm. Comparisons have been made with quantum PSO, cooperative quantum PSO, multi swarm based hybrid PSO, the newly developed multi swarm versions of quantum PSO and cooperative quantum PSO algorithms. Studies clearly indicate that multi swarm version of quantum PSO algorithms are more consistent and also reliable in providing optimal solutions. The methods presented in this paper will be applicable in general to the design of laminate composite structures.