A numerical study of shock-induced hot spot generation in energetic material

This thesis studies the formation of hot spots in energetic materials by shock initiation. A mathematical model has been developed based on viscoplastic pore collapse mechanics. Governing equations for the condensed-phase and gas-phase dynamics are derived which contain important processes including viscoplastic heating, finite-rate reaction, mass transfer and heat exchange. The system of equations are solved with two different numerical techniques. Through integration and scaling considerations, a simplifi ed model, referred to as the space-averaging model, is firstly introduced. This model generates efficient prediction to pore collapse and expansion by solving a set of ordinary diff erential equations in the gas phase. Besides, a discrete model that directly solves the partial differential governing equations for the gas-phase is also developed. Detailed information about the gas phase reaction, such as temperature, mass fraction and density distributions, can be obtained from the results. The governing equations, together with the initial and interface conditions, are solved numerically for a series of test cases for RDX (C3H6N6O6) and HMX (C4H8N8O8). The results shows that viscoplastic heating is an effective mechanism in the ignition of shocked energetic materials. In addition, it is demonstrated that the material porosity and the initial pore size have strong influence on the hot spot formation.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Aerospace Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2013

Author dc:creator

• Zhang, Yang

Contributors dc:contributor

• Jackson, Thomas L.

• energetic material
• hot spot generation
• numerical simulation

Statement dc:rights

• Copyright 2013 Yang Zhang

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/45378

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/45378