Design and testing of a composite pressure hull for deep autonomous underwater vehicles.
This paper presents the design and testing process of the hull of a deep small autonomous underwater vehicle, rated at 2000m depth. Starting from setting the geometrical constraints for the design to mass production. None of the previous literature, to the authors’ knowledge has presented similar work. Carbon Fiber Reinforced Epoxy material was chosen given their high strength to weight ratio and similarity of its compressibility to sea water. Material characterization was performed to obtain the material properties under loading conditions using a modified method of the Combined Loading Compression testing technique. A specific fixture was designed and manufactured to test filament-wound tubes. An analytical model was developed on MATLAB, a finite element model was created on ABAQUS, and the results of both models were compared. Then a quality control set of tests was performed including seawater absorption under high pressure and void analysis using destructive and non-destructive tests. Pilot samples were manufactured and tested in a pressure vessel, where one was cycle tested and inspected using visual and ultrasonic testing, and the other one was fail tested where it failed at ~93% of the expected load.