Design optimization of composite fan blade in aircraft engine subjected to bird strike loading

Bird strike has been a perennial problem for all airline companies in the world. It is the most important design criteria for the fan blades of an aircraft engine. As it is not possible to manufacture and test aircraft engines again and again for small design changes, through the simulation analysis, it is possible to study the ways to reduce the impact of the bird on a jet engine by using appropriate design and manufacturing methods for the blade. This research suggests using two fibers (hybrid) in place of the single fiber composite blade which is currently in use to reduce the delamination issues. In the first stage of this research, representative composite coupon models for combinations of hybrid fiber joint positions were created and linear static analysis was performed. For the validation of simulation methodology, a few coupons were manufactured and tested in the laboratory. Further, dynamic bird strike analysis on sub-element level models was carried out in the second stage with various joint location combinations. Next, the plate-level representative blade model was designed with the original dimensions of the aircraft engine fan blade, and bird strike analysis was performed. The behavior of the representative plate with hybrid interface was studied, and the levels of inter-laminar shear strain were checked, by varying the joint location of the two composites. Some of the shortlisted cases do show significant promise of being damage tolerant under bird strike loading.