The lab has performed work and collaborated on various other research topics. These include Richtymer-Meshkov Instability, ejecta formation, magnetohydrodynamic mixing, and nano-particle reactions. We are always looking for new collaborations that leverage our interest and capabilities.
Richtmyer-Meshkov Instability
The Richtmyer-Meshkov Instability (RMI) is driven by the impulsive acceleration of a perturbed interface between two fluids of different densities. The shock deposits baroclinic vorticity at the interface, and the perturbations grow through the linear and nonlinear stages, and eventually to a state of decaying turbulence. The baroclinic term of the vorticity equation is proportional to the misalignment between the density and pressure gradients. The strength of the RMI can be quantified by the Atwood number which describes the interface density gradient, and the incident shock wave Mach number, describing the pressure gradient.
We have collaborated with Los Alamos and Lawrence Livermore National Laboratories and with Prof. Devesh Ranjan and Dr. Mohammad Mohaghar of Georgia Tech on this research topic.
Ejecta Formation
Ejecta can be produced from a Richtmyer-Meshkov instability (RMI) acting on a solid interface. When the shock is sufficiently strong, the material will yield and flow like a fluid. In some cases the interface will melt. As the RMI spikes elongate, they begin to breakup into particles or droplets. These particles are ejected at high velocity away from the original solid interface becoming ejecta.
We have worked with Los Alamos National Laboratory and Prof. Praveen Ramaprabhu on this research area.
Magnetohydrodynamic Richtmyer-Meshkov Instability
The Richtmyer-Meshkov Instability occurs when an interface between fluid of different densities is accelerated by a shock wave. When one or both of these fluids is conducting, it can react to the presence of a magnetic field. The resulting magnetohydrodynamic effects can suppress the mixing normally observed in the Richtmyer-Meshkov Instability.
We have collaborated with Los Alamos and Lawrence Livermore National Laboratories on this research topic.
Nano-Particle Reactions
Nano-sized metal particles show a drastically increased reactivity that can be leveraged in thermites, explosives, and solid fuels. The reason for this increased reactivity is poorly understood. Nano-partilces, such as aluminum, have a passive shell layer (Al2O3 in this case). One explanation for the increased reactivity is that this shell fails from internal stresses due to heating, melting, and possibly vaporization of the aluminum core. This results in an explosive decompression, which sends reactive ejecta particles out into the surrounding oxidizing material, which subsequently react at much higher rates.
we collaborated with Profs. Shubhra Gangopadhyay , Keshab Gangopadhyay, and Matt Maschmann at the University of Missouri.