Delphine M. Laboureur

Case study and lessons learned from the ammonium nitrate explosion at the West Fertilizer facility

In West, Texas on April 17, 2013, a chemical storage and distribution facility caught fire followed by the explosion of around 30 tons of ammonium nitrate while the emergency responders were trying to extinguish the fire, leading to 15 fatalities and numerous buildings, businesses and homes destroyed or damaged. This incident resulted in devastating consequences for the community around the facility, and shed light on a need to improve the safety management of local small businesses similar to the West facility. As no official report on the findings of the incident has been released yet, this article first investigates the root causes of the incident, and presents a simplified consequence analysis. The article reviews the regulations applicable to this type of facility and recommended emergency response procedures to identify gaps between what happened in West and the current regulations, and discusses how the current regulations could be modified to prevent or minimize future losses. Finally, the federal response that followed the incident until the publication of this paper is summarized.

BLEVE overpressure: Multiscale comparison of blast wave modeling

BLEVE overpressure modeling has been already widely studied but only few validations including the scale effect have been made. After a short overview of the main models available in literature, a comparison is done with different scales of measurements, taken from previous studies or coming from experiments performed in the frame of this research project. A discussion on the best model to use in different cases is finally proposed.

Investigation of the Taylor-Culick Flow Through Particle Image Velocimetry and Numerical Simulation

DOI: 10.2514/1.44616 The Taylor–Culick flow corresponds to the flow injection through the lateral wall of a semi-infinite channel. This flow is intrinsically unstable downstream of a critical axial position. The flow disturbances develop in vortices that could couple with the acoustics of the channel, generating pressure oscillations. This is what occurs in large solid rocket motors in which the Taylor flow is induced by the propellant combustion. Depending mainly on the Reynolds number, three different flow regimes can be observed: laminar, transitional, or turbulent. The current paper presents an experimental and numerical investigation of that flow instability. The setup consists of a rectangular shape channel in which air is introduced through the bottom wall due to a porous plate. Quantitative measurements are performed with particle image velocimetry while unsteady numerical simulations are carried out using large eddy simulation. A special injection system for the seeding particles and a special arrangement for the laser sheet provide good quality particle image velocimetry data. The numerical simulations are validated against the particle image velocimetry results. They complete the particle image velocimetry investigation by following chronologically theinstantaneousphenomenon.Theexperimentsandthenumericalsimulationsareperformedatdifferentinjection velocities and channel heights.

Small Scale Experiments on Boiling Liquid Expanding Vapor Explosions: Supercritical BLEVE

The most dangerous accident that can occur in LPG storage is the boiling liquid expanding vapor explosion (BLEVE). To better understand the rupture of the reservoir and the blast wave characteristics, small scale BLEVE experiments are performed with cylinders of 95 ml, filled at 86% with propane, laid horizontally and heated from below. A weakening of the reservoirs on the upper part allows better reproducibility of the rupture. High speed visualization, blast overpressure and surface reservoir temperature are measured.Internal pressure measurement shows that the rupture pressure and temperature are well above the critical point. The fluid is then supercritical and there is no distinction anymore between liquid and gas prior rupture. This kind of reservoir rupture is significant of a new type of BLEVE, a supercritical BLEVE. The experiments also show that the fluid behavior during rupture differs with the size of the weakened part and therefore with the rupture pressure. Finally, the measured peak overpressures are compared with literature models.Copyright

Experimental and Numerical Investigation of Taylor Flow in a Cold Flow Model of SRM

ow regimes can be observed: laminar, transitional or turbulent. The current paper presents an experimental and numerical investigation of that SVS instability. The set-up consists of a rectangular shape channel in which air is introduced through the bottom wall thanks to a porous plate. Quantitative measurements are performed with Particle Image Velocimetry (PIV) while unsteady numerical simulations are carried out using a commercial solver (Fluent). A special injection system for the seeding particles and a special arrangement for the laser sheet provide good quality PIV data. The numerical simulations are performed using the Large Eddy Simulation module of Fluent and are validated against the PIV results. They complete the PIV investigation by following chronologically the instantaneous phenomenon. The experiments and the numerical simulations are performed at dierent injection velocities and channel heights in order to represent the dierent ow regimes.