PERSEUS, Episode IV - A new Hope: Design, modelling and prototyping of a single-material composite tank for cryogenic propellant storage
Creators: name:  M. GALEOTTA 
name:   T. BRIAND 
name:   J. BENABES 
name:   A. LAVAUD 
name:   E. CARCANO 
name:   J. MAZEL 
Publisher: name: Proceedings of  the 9th European Conference for Aerospace Sciences. Lille, France, 27 June - 1 July, 2022
Year: 2022
Subjects: SPACE
ADVANCED TECHNOLOGIES
REUSABILITY

description: The development of the space industry requires a significant reduction in the costs of manufacturing and launching launchers. One of the main lines of research related to this problem lies in the manufacture of composite tanks without liner for the storage of liquid propellants. The sizing of V-type tanks, without metallic or polymer liner, is managed by the tightness criterion critical before the resistance criterion in order to avoid the leakage of the structure. For the storage of cryogenic fluids (LN2, LHe, LCH4), the problems of differential expansion at the micro and mesoscopic scales as well as the evolution of the mechanical characteristics of materials when the temperature decreases are major phenomena for the design. Sizing becomes more complex when the cryogenic fluids are specific (LOX) because the problem of compatibility between the fluid and the materials of the tank strongly limits the choice of the components of the structure. In the framework of the PERSEUS project, CMP Composites in collaboration with the CNES is developing a single material composite tank (boss, liner, structure, skirt) for the next bi-liquid launcher ASTREOS. This development is based on an innovative design involving several composite manufacturing processes (infusion and filament winding). The \"one-shot\" infusion of half-liners/boss, glued together afterwards, allows the integration of specific systems (anti-vortex, anti-sloshing, diffuser) inside the tank during the manufacturing process. At this stage of the manufacturing process, it is also possible to apply an internal coating to the tank in order to improve the tank\'s tightness and/or the compatibility of the structure with the stored fluid. After the assembly of the half-liners/boss, the structure of the tank, sized according on a matrix cracking criterion for the absorption of the pressurization forces, is produced by filament winding. Finally, with the help of dedicated tools, the skirt part of the tank is over-wound on the tank in order to hold the structural efforts due to the launch. A stamping test at room temperature was successfully conducted and validated the mechanical strength of the single-material composite tank for ethanol storage. The filling of this same tank with liquid nitrogen also allows to validate the good behaviour of the tank at -196C. Finally, pressurization tests in liquid nitrogen and liquid oxygen environments will allow to finish the validation of the tank under increasing complexity loading. This paper proposes a global description of our work on the composite cryogenic tank. First, we present the design strategy based on a numerical approach with a modelling of the elastic behaviour of the composite at the mesoscopic scale. This first step allows us to validate the global criteria of the structure (strength and stiffness) and to evaluate the criticality of the different joints. Then, the validation strategy of these joints will be presented. The implementation of a test-calculation dialogue allows us to link the forces at rupture of the links to a stress level within the material which establishes a sizing criterion for the joints on the tank structure. We will also present the different manufacturing processes of the tank, including the material analysis of the different sub-assemblies that allowed the validation of these processes (fibre rate, porosity rate). Finally, the validation tests of the tank will be presented as well as a correlation with the calculation models that allowed the sizing of the structure. We purpose a discussion of the results obtained on these first tanks in order to conclude on the technologies and the innovative concepts developed by the CNES and CMP Composites. Perspectives to this work still in progress of evolution and optimization will be finally described.