Liquid Propellant Blast Yields for Delta IV Heavy Vehicles
Abstract
Launch vehicle propulsion systems contain liquid propellants that may mix and explode when impacting the ground intact following launch attempts failing early in flight. Launch area risk analysis tools characterize the air shock potential of promptly reacting liquid propellants in these events using models of the blast yield as a function of propellant material, weight, impact velocity, and impact surface hardness. Air blast yields from these events are typically described in terms of the ratio of the equivalent weight of TNT to the total weight of the propellant involved, based on the air shock overpressure generated. The Delta IV Heavy is unique among currently operating heavy space lift vehicles in both size and configuration, with three Common Booster Cores (CBCs), each containing some 450,000 lb of liquid propellants. The blast yield model for all three CBCs exploding simultaneously during an intact impact may be excessively conservative. Recent hydrocode simulations show significant time delays between the development of fuel and oxidizer mixing interfaces in adjacent CBC bulkheads. Early mixing of propellants in a CBC may lead to the dispersal of propellants in adjacent CBCs that would otherwise mix and react promptly. This suggests that only one or two CBCs are likely to contribute significantly to the overall blast yield. Further confirmation of this finding may be possible with higher fidelity simulations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2010
- Accession Number
- ADA532286
Entities
People
- Ron R. Lambert