Methodology Development and Validation of Weight Optimized Stiffeners Run-Out Design for Future Composite Wings
Date
Brief relate
DOVER has aimed to develop a design optimization tool and methodology dedicated to supporting the design of innovatively designed and weight-optimized composite stiffened panel configurations with the ability to improve all areas and configuration parameters such as geometries, stacking sequences or anti-peeling rivets. The precision and reliability of the resulting methodology have been validated through experimental tests.
DOVER's solution proposal has been the creation and validation of a design tool and methodology allowing the optimization of the structural stiffened composite panels of the wings. The developed tool provides an environment for the investigation of innovative lightweight designs, including the geometry of the reinforcement, the thickness and arrangement of the different components, the shape of the taper or the configuration of the anti-peeling rivets. Using this tool, the designer can predict the failure of any run-out configuration of the stiffeners and obtain a global optimization of the panel with considerable time savings, since it does not require complex numerical models to predict the behavior, and economically, since It is not necessary to carry out expensive test campaigns.
To achieve this solution, DOVER has been structured in different stages that ensure maximum quality, precision and reliability. Through an initial experimental study of the behavior of the stiffened panel, an experimental basis is established that is used to develop a model and generate a methodology for predicting the appearance of failure. This methodology is put into practice by designing different innovative stiffened panel configurations. The optimized solutions are evaluated and correlated with the experimental results. To this end, in a final stage, mono-stiffened panels have been manufactured, and stresses and deformations have been obtained at the time of failure to validate the development.
The work carried out to achieve the aforementioned objectives has been structured into four main tasks:
Task 1.- Definition of the test campaigns, manufacture of specimens and execution of the initial test campaigns, including impact on specimens, traction and compression tests, both static and fatigue after impact, and performance of these tests at room temperature, in cold conditions and in humid and hot conditions.
Task 2.- Preparation of finite element models, correlating their results with the results obtained experimentally for the subsequent development of a methodology and a criterion that allows predicting the onset of failure.
Task 3.- Development of innovative stiffened panels through optimization strategies in simple finite element models using the project methodology.
Task 4.- Validation of the new designs through experimental tests on mono-stiffened specimens under traction and compression with both static loads and fatigue after impact.
