Manufacturing Composite External Volumes with Enhanced Underwater Collapse Performance

This proposal will identify critical factors that can result in reduced performance of a filament wound composite shell by purposeful alteration of a baseline composite design and manufacturing process.  Finite Element (FE) models will be created to predict the hydrostatic collapse pressure capability of a given composite design.  The composite designs will be implemented by carefully controlled filament winding processes.  Nondestructive Evaluation (NDE) methods such as ultrasonics (UT) and acoustic emission (AE) will be developed to measure, inspect and characterize the filament wound composite structure(s).  These structures will be subjected to external pressurization testing by HyPerComp Engineering (HEI) to determine initiation of buckling and hydrostatic collapse pressure. Subsequently, the HEI team of investigators will evaluate and correlate the results of pressurization testing with the FE models.  These efforts will result in an enhanced filament winding process model for the fabrication and inspection of composite shells to be used in aquatic sub-surface external volume applications.   One of the strongest aspects of this proposal is the relevant knowledge and experience of the individual investigators that will be involved in this program.  Together as a team these individuals will provide the expertise necessary to properly address the technical objectives of this program.   Phase I Technical Objectives HEI’s proposed effort meets the objectives of determining how composite design, materials and filament winding processes affect the quality and hydrostatic collapse response of composite pressure housings as identified in the SBIR solicitation along with additional objectives as deemed necessary.   The primary technical objectives of this proposal are: Design filament wound structures and create Finite Element (FE) models of these structures Build and test filament wound composite shells Explore and apply NDE methods to develop an acceptance plan for filament wound composite shells   Additional technical objectives, which are necessary to the satisfactory completion of the Phase I program, include: Identify storage and operational environment(s), and detailed design requirements Create FE models applicable to the design of filament wound composite shells Fabricate filament wound composite shells using FE design models Identify NDE methods of inspection for measuring/evaluating filament wound composite shells Perform (external) hydrostatic pressure testing of filament wound composite shells in conjunction with NDE measurements Evaluate and correlate results of hydrostatic pressure testing with FE design models and NDE