Composite structures are increasingly being used within the aircraft industry. However, the application of composites within impact endangered areas is limited. In cooperation with Airbus, DLR, Institute of structures and Design, and EADS Innovation Works, a new advanced thermoplastic composite slat, based on the A340 aluminium slat 4, has been developed with the aim of minimizing weight and manufacturing costs. In addition to linear static analysis using NASTRAN, dynamic high velocity impact simulations were carried out. The objective was to calculate a bird strike impact on the composite slat using the Smoothed Particle Hydrodynamics (SPH) option of PAMCRASH. The numerical analysis was validated with Wilbeck tests using a gelatine bird substitute. Furthermore the implemented composite damage model according to Ladeveze was validated with 2 experimental impact tests. A sensitivity of the gelatine bird regarding the impact behaviour was identified. Several generic and one thermoplastic demonstrator section with a scale 1:1 cross section were manufactured. The critical points concerning the stacking and consolidation of thick tapered thermoplastic plates were identified and new manufacturing methods were developed. Additionally, the thermoplastic welding process was improved resulting in a low cost assembly technique as alternative to current joining methods, such as riveting. A numerical approach for high velocity bird strike impact has been shown. The results were used to dimension the residual strength of a damaged slat. A good compliance between the dynamic analysis and the test has been reached. It has been shown that a significant weight reduction of a slat structure seems feasible by numerical optimization even if composite materials are used for impact sensitive areas.
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