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Title: Quantification of initial-data uncertainty on a shock-accelerated gas cylinder

Abstract

We quantify initial-data uncertainties on a shock accelerated heavy-gas cylinder by two-dimensional well-resolved direct numerical simulations. A high-resolution compressible multicomponent flow simulation model is coupled with a polynomial chaos expansion to propagate the initial-data uncertainties to the output quantities of interest. The initial flow configuration follows previous experimental and numerical works of the shock accelerated heavy-gas cylinder. We investigate three main initial-data uncertainties, (i) shock Mach number, (ii) contamination of SF{sub 6} with acetone, and (iii) initial deviations of the heavy-gas region from a perfect cylindrical shape. The impact of initial-data uncertainties on the mixing process is examined. The results suggest that the mixing process is highly sensitive to input variations of shock Mach number and acetone contamination. Additionally, our results indicate that the measured shock Mach number in the experiment of Tomkins et al. [“An experimental investigation of mixing mechanisms in shock-accelerated flow,” J. Fluid. Mech. 611, 131 (2008)] and the estimated contamination of the SF{sub 6} region with acetone [S. K. Shankar, S. Kawai, and S. K. Lele, “Two-dimensional viscous flow simulation of a shock accelerated heavy gas cylinder,” Phys. Fluids 23, 024102 (2011)] exhibit deviations from those that lead to best agreement between our simulations and themore » experiment in terms of overall flow evolution.« less

Authors:
; ; ; ;  [1]
  1. Institute of Aerodynamics and Fluid Mechanics, Technische Universität München, 85747 Garching (Germany)
Publication Date:
OSTI Identifier:
22257090
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Fluids (1994); Journal Volume: 26; Journal Issue: 2; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACETONE; CHAOS THEORY; COMPUTERIZED SIMULATION; FLUIDS; GAS CYLINDERS; MACH NUMBER; POLYNOMIALS; SULFUR FLUORIDES; THERMAL EXPANSION; VISCOUS FLOW

Citation Formats

Tritschler, V. K., E-mail: volker.tritschler@aer.mw.tum.de, Avdonin, A., Hickel, S., Hu, X. Y., and Adams, N. A.. Quantification of initial-data uncertainty on a shock-accelerated gas cylinder. United States: N. p., 2014. Web. doi:10.1063/1.4865756.
Tritschler, V. K., E-mail: volker.tritschler@aer.mw.tum.de, Avdonin, A., Hickel, S., Hu, X. Y., & Adams, N. A.. Quantification of initial-data uncertainty on a shock-accelerated gas cylinder. United States. doi:10.1063/1.4865756.
Tritschler, V. K., E-mail: volker.tritschler@aer.mw.tum.de, Avdonin, A., Hickel, S., Hu, X. Y., and Adams, N. A.. 2014. "Quantification of initial-data uncertainty on a shock-accelerated gas cylinder". United States. doi:10.1063/1.4865756.
@article{osti_22257090,
title = {Quantification of initial-data uncertainty on a shock-accelerated gas cylinder},
author = {Tritschler, V. K., E-mail: volker.tritschler@aer.mw.tum.de and Avdonin, A. and Hickel, S. and Hu, X. Y. and Adams, N. A.},
abstractNote = {We quantify initial-data uncertainties on a shock accelerated heavy-gas cylinder by two-dimensional well-resolved direct numerical simulations. A high-resolution compressible multicomponent flow simulation model is coupled with a polynomial chaos expansion to propagate the initial-data uncertainties to the output quantities of interest. The initial flow configuration follows previous experimental and numerical works of the shock accelerated heavy-gas cylinder. We investigate three main initial-data uncertainties, (i) shock Mach number, (ii) contamination of SF{sub 6} with acetone, and (iii) initial deviations of the heavy-gas region from a perfect cylindrical shape. The impact of initial-data uncertainties on the mixing process is examined. The results suggest that the mixing process is highly sensitive to input variations of shock Mach number and acetone contamination. Additionally, our results indicate that the measured shock Mach number in the experiment of Tomkins et al. [“An experimental investigation of mixing mechanisms in shock-accelerated flow,” J. Fluid. Mech. 611, 131 (2008)] and the estimated contamination of the SF{sub 6} region with acetone [S. K. Shankar, S. Kawai, and S. K. Lele, “Two-dimensional viscous flow simulation of a shock accelerated heavy gas cylinder,” Phys. Fluids 23, 024102 (2011)] exhibit deviations from those that lead to best agreement between our simulations and the experiment in terms of overall flow evolution.},
doi = {10.1063/1.4865756},
journal = {Physics of Fluids (1994)},
number = 2,
volume = 26,
place = {United States},
year = 2014,
month = 2
}
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