Assessment of Design and Durability Issues for Composite NGV Fuel Cylinders.Final Topical Report, October 1991-February 1994

摘要

Research on advanced compressed natural gas (CNG) cylinders, consisting of acomposite overwrap and a metallic or nonmetallic liner, is reviewed. Specific conclusions from the review are that these cylinders are unlikely to fail in the short term, but failure, if it does occur, is more likely to result from progressive degradation over time, which may occur as a result of liner or overwrap failure. Analytical models to predict cylinder failure are reviewed. NDE and smart-structure concepts for CNG cylinders are also considered and ultrasonic and acoustic emission techniques are shown to be most promising. A conclusion from the review is that the desired 15-year life for CNG cylinders for NGVs, proposed in the NGV-2 standard, is achievable but is predicted on the trade-off between inspection at manufacture, in-service inspection, or extensive design and manufacture that ensures no premature cylinder failures.