Optimizing AFP Manufactured Composite-Based Cryogenic Tanks for Space-Based Missions

Abstract

When going into space, rockets need to keep their liquid hydrogen fuel at a very low temperatureto maintain its liquid state and minimize the amount that boils away and escapes. This means its propellant tank must have good mechanical properties at incredibly low temperatures. Yet there is an added challenge when going into space; this fuel is not cheap by any stretch of the imagination. Carbon fiber has become a very popular material in the aerospace industry for its fantastic mechanical properties [1] and exceptional weight-tostrength ratio [2]. In this thesis, we will look at designing and optimizing a cryogenic rocket propellant tank made completely out of Carbon Fiber Reinforced Composite (CFRC) to make it as strong as necessary yet as light as possible. These structures are not often optimized in very rigorous detail, missing out on what can be significant weight savings for the structure and in turn the entire rocket. Structures such as this are optimized via state-of-the-art software and compared to traditional design both in terms of performance and manufacturability. Three different optimized layups are introduced and compared to a benchmark industry design in terms of their weights, mechanical strengths, and abilities to be manufactured using automatic fiber placement (AFP).