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Imaging perturbed shock propagation in powders

Review of Scientific Instruments

Cooper, Marcia A.; Guo, Shuyue G.; Sapp, Adam W.; Vogler, Tracy V.

A novel experimental methodology is presented to study the deviatoric response of powders in shock regimes. The powders are confined to a cylindrical wedge volume, and a projectile-driven shock wave with a sinusoidally varying front propagates through the powder. The perturbed shock wave exhibits a damping behavior due to irreversible processes of viscosity and strength (deviatoric) of the powder with propagation through increasing powder thicknesses. The inclined surface of the wedge is polished and coated to establish a diffuse surface suitable for reflecting incident laser light into a high-speed camera imaging at 5 MHz. Images of the contrast loss upon shock wave arrival at the observation surface are post-processed for qualitative and quantitative information. New data of shock damping behavior with parameters of perturbation wavelength and initial shock strength are presented for powders of copper, tantalum, and tungsten carbide as well as their mixtures. We present the first full-field images showing additional spatial disturbances on the perturbed shock front that appear dependent on particle material and morphology.

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TYPE Journal Article YEAR 2020
DOIOSTIScopus

A COLD ATOM INTERFEROMETRY SENSOR PLATFORM BASED ON DIFFRACTIVE OPTICS AND INTEGRATED PHOTONICS

Lee, Jongmin L.; McGuinness, Hayden J.; Soh, Daniel B.; Christensen, Justin C.; Ding, Roger D.; Finnegan, Patrick S.; Hoth, Gregory W.; Kindel, William K.; Little, Bethany J.; Rosenthal, Randy R.; Wendt, Joel R.; Lentine, Anthony L.; Eichenfield, Matthew S.; Gehl, M.; Kodigala, Ashok; Siddiqui, Aleem M.; Skogen, Erik J.; Vawter, Gregory A.; Ison, Aaron M.; Bossert, David B.; Fuerschbach, Kyle H.; Gillund, Daniel P.; Walker, Charles A.; De Smet, Dennis J.; Brashar, Connor B.; Berg, Joseph B.; Jhaveri, Prabodh M.; Smith, Tony G.; Kemme, S.A.; Schwindt, Peter S.; Biedermann, Grant

Abstract not provided.

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TYPE Conference Poster YEAR 2020
OSTI

Synchrotron characterization of high-Z, current-mode X-ray detectors

Review of Scientific Instruments

Looker, Quinn M.; Wood, Michael G.; Miceli, Antonino; Niraula, Madan; Yasuda, Kazuhito; Porter, John L.

Fast X-ray detectors are critical tools in pulsed power and fusion applications, where detector impulse response of a nanosecond or better is often required. Semiconductor detectors can create fast, sensitive devices with extensive operational flexibility. There is typically a trade-off between detector sensitivity and speed, but higher atomic number absorbers can increase hard X-ray absorption without increasing the charge collection time, provided carriers achieve high velocity. This paper presents X-ray pulse characterization conducted at the Advanced Photon Source of X-ray absorption efficiency and temporal impulse response of current-mode semiconductor X-ray detectors composed of Si, GaAs, and CdTe.

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TYPE Journal Article YEAR 2020
DOIOSTIScopus

Optimal Distribution System Voltage Regulation using State Estimation and DER Grid-Support Functions

Johnson, Jay

Increasing solar energy penetrations may create challenges for distribution system operations because production variability can lead to large voltage deviations or protection system miscoordination. Instituting advanced management systems on distribution systems is one promising method for combating these challenges by intelligently controlling distribution assets to regulate voltage and ensure protection safety margins. While it is generally not the case today, greater deployment of power system sensors and interoperable distributed energy resources (DER)e.g., photovoltaic (PV) inverters, energy storage systems (ESS), electric vehicles (EVs)will enable situational awareness, control, and optimization of distribution systems. In this work, a control system was created which measures power system parameters to estimate the status of a feeder, forecasts the distribution state over a short-term horizon, and issues optimal set point commands to distribution-connected equipment to regulate voltage and protect the system. This two-year project integrated multiple research innovations into a management system designed to safely allow PV penetrations of 50% or greater. The integrated software was demonstrated through extensive real-time (RT) and power hardware-in-the-loop studies and a field demonstration on a live power system with a 684 kVA PV system.

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TYPE SAND Report YEAR 2020
DOIOSTI
Results 16801–17000 of 96,771
Results 16801–17000 of 96,771