In the frame of the preparation of the future and innovative works in CNES, it is asked to design a new structure for rear part of a launcher. The use of topology, shape and size optimizations is demonstrated as an appropriate logic to find new concepts with lower mass and better performances with regard to usual structural concepts for launchers.
A first concept already optimized with a size optimization module is used as a reference.
The selected structure is a cylindrical skirt located on the rear part of Ariane 6 central booster. The loads coming from the lateral boosters are applied through their resultant forces on this skirt structure. Aluminium alloy is selected and the concept of reference uses frames and stiffeners on the whole structure and reinforcing boxes for its lowest part.
The agreed logic by CNES and EnginSoft was the realization of:
The main goals are mass reduction and proposal of innovative concepts but with low production cost.
At the end, a gain exceeding 30% in term of mass and potential design simplifications were obtained.