Numerical Simulations of Pressure Spikes within a Cylindrical Launch Tube due to a Bursting Helium Flask
Abstract
A numerical model to simulate the bursting of a high-pressure flask of helium gas located within a cylindrical launch tube is described. The model provides an upper estimate for the launch tube wall pressures by assuming that the helium flask failure can be treated as a bursting balloon. The gas dynamic equations for the expansion of the 5000 psig helium region are solved utilizing the finite element program FlexPDE to obtain time-dependent solutions for pressure, gas density, and velocity. The work is motivated by a desire to understand and interpret field tests conducted by NRL at Blossom Point in June 2010, for the experimental fuel cell (XFC) unmanned aerial system (UAS). The primary objective of these tests was to determine the failure mode of the hydrogen fuel flask and the extent of fragmentation damage. The test demonstrated that the fragmentation damage to the XFC launcher tube was minimal. Launch tube side wall and end cap pressure-time measurements were also recorded during the flasks burst for both helium and hydrogen gases. This transducer data is compared with the numerical simulations of the gas dynamic model.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 09, 2011
- Accession Number
- ADA552671
Entities
People
- Benjamin D. Gould
- Harold D. Ladouceur
Organizations
- United States Naval Research Laboratory