Hayesian inference: Exploring the relationship between supercritical hot spot number density and the speed of burn waves they trigger

• Main Authors: Hill, Larry G., Aslam, Tariq D., Mang, Joseph T.
• Format: Conference Proceeding
• Language: English
• Subjects: Density; Detonation; Shock waves
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/12.0032446

On January 2, 2023, the SCCM community lost one of its most senior and vital members: Dennis B. Hayes, formerly of Sandia National Laboratories, and subsequently of Lockheed Martin Nevada. Although Dennis was primarily known as a shock-wave and equation-of-state theorist, he made forays into x-rays, detonation, and other topics. He independently derived the Statistical Hot Spot (SHS) model in 1981, and was the first to apply it to reaction in shocked explosives. Dennis realized that, given a modeled estimate for burn fraction, λ, and the number density of sufficiently supercritical hot-spots, η, one may use SHS to infer the elusive speed, V̄, of hot-spot-initiated burn waves. This he did for experiments on shock-initiated porous HNS explosive. He estimated η based on simple arguments about granularity, and hence (via SHS) V̄, which he predicted to be 3.6 to 50 m/s depending on conditions. These estimates are generally consistent with more recent measurements and simulations. Here we refine his method using modern instruments and models—and use it to explore the η-V̄ relationship for PBXs 9501 and 9502.