Tabletop Shock Compression of Liquids Under a Microscope: From Liquid Water to Explosive Nitromethane

Erin Nissen, University of Illinois at Urbana-Champaign

Photo of Erin Nissen

We have developed a table-top method for generating reproducible planar shock waves in liquid samples through the impact of a laser-driven flyer plate. The velocity of the flyer plate is measured with photon Doppler velocimetry (PDV) to determine the pressure of either water or nitromethane in each cuvette. The sample array consists of 55-125 cuvettes, enabling a high-throughput of individual experiments. This platform allows us to probe pure water itself and various molecules in solution with different forms of spectroscopy. The photophysics of shock-compressed Rhodamine 6G in liquid water is presented here as an example. The shock-induced changes in fluorescence are used to measure the local environment of the water using a nanosecond laser and streak camera. Additionally, the versatility of this method permits us to study other interesting liquids, such as nitromethane. Using our home-built optical pyrometer, fast-gated intensified CCD and PDV, we are able to accurately track the reaction threshold by collecting radiance and temperature profiles at different flyer velocities, image a homogeneous liquid explosion and determine the energy input/output of each shot.

Abstract Author(s): Erin J. Nissen, Mithun Bhomick, Dana D. Dlott