Confined Blast

Confined Blast is an engineering tool suite used to characterize airblast and debris hazards from a confined explosion to support explosives safety protective design submittals for the U.S. Department of Defense Explosives Safety Board (DDESB). The tool suite consists of the SHOCK, FRANG, MUDEMIMP, and TP 13 analysis programs. The SHOCK program calculates incident and reflected shock pressures and impulses on interior surfaces of a donor/containment structure in accordance with UFC 3-340-02. The FRANG program performs a time-dependent analysis of gas pressure and impulse build-up within a donor/containment structure in accordance with UFC 3-340-02. FRANG captures the influence of open vents, covered vents, and frangible wall/roof panels on total gas impulse within the donor/containment structure. The MUDEMIMP (Multiple Debris Missile Impact Simulation) program is used to determine the hazardous debris distance and debris dispersion for a donor structure. The program uses a probabilistic approach to include variation and uncertainties in launch/flight characteristics of each individual piece of debris from a confined explosion. It uses the Monte-Carlo random sampling technique to select a set of launch/flight parameters for each piece of debris. From there, MUDEMIMP calculates the trajectory, impact range, and terminal kinetic energy of each piece of debris based on prescribed initial conditions. The TP 13 module of Confined Blast makes use of SHOCK, FRANG, and MUDEMIMP to analyze safe distances for unhardened facilities due to the hazard of blast fragments and debris from a confined explosion in accordance with DDESB Technical Paper 13.