Colloquium: Akshay Kulkarni (ASM)

The kick stage is an additional stage on the top of the upper stage of the Ariane 6 launch vehicle. The propellant tanks are a dominant load of the kick stage and they are located along an off-axis with respect to the launcher's central axis. The scope of thesis research project is the development of a lightweight design methodology for the main structure that constrains the heavy propellant tanks against mechanical loads particularly dynamic loads. 
Structural optimization methods with OptiStruct FEM solver are the tools used for the design development. Initially, topology optimization principles are used to generate the design critical regions from the total design space. Afterwards, size optimization methods are implemented to modify the design to meet the design constraints. In addition, an innovative design using composite grid structure methodology is proposed and analyzed for the primary loading conditions.
The results indicate that a combination of topology and size optimization help to create stiffer structures while meeting the dynamic requirements and the design performance can be scaled to match per input dynamic load. Additionally, the anisogrid composite design for cylinders under compressive loading is a promising lightweight solution for improving buckling and dynamic performance of spacecraft central core.

Supervisor: Dr. Ing. S.G.P. (Saullo) Castro