Abstract Details
Modeling of fabrication uncertainties in the simulation of supernova hydrodynamics experiments
Author: Adam M. Budde
Requested Type: Oral Only
Submitted: 2009-04-27 22:16:14
Co-authors: R.P.Drake, C.C.Kuranz, T.Plewa, N.Hearn
Contact Info:
University of Michigan
2455 Hayward St.
Ann Arbor, MI 48374
United States
Abstract Text:
Recent experiments have used ~ 5 kJ of energy from the Omega Laser to create a blast wave similar to one that occurs at the He-H interface in a core-collapse supernova. The blast wave crosses an interface with a drop in density, which induces growth of a seed perturbation on the interface due to the Rayleigh-Taylor instability. These experiments have exhibited different morphology than our simulations predict. It has been hypothesized that such morphology may be due to unintended structures created in the target fabrication process.
The key components of the target are a 150 µm thick plastic disk followed by a few millimeters of low-density foam. The plastic disk has a 250 µm wide, 75 µm deep slot milled out of one side. A diagnostic tracer material is glued into the slot and the seed perturbation is machined onto the entire surface of the disk. The perturbation is 3D with a basic structure of two orthogonal sine waves each with a wavelength of 71 µm and an overall amplitude of 2.5 µm. In the experiments, the epoxy used to affix the tracer layer could affect the evolution of the instability growth. Also, in some cases the machining of the pattern has caused the tracer layer to be significantly lower than the surrounding material.
2D and 3D FLASH simulations have been used to model such experimental target variations and are presented here. These simulations are performed with 50 zones per wavelength resolution using an Eulerian mesh. The target walls are modeled using periodic boundaries for 3D simulations and reflective boundaries for 2D simulations. Initial laser conditions for all experiments are imported from a 1D HYADES simulation. The results of these simulations will be shown.
This research was sponsored by the Stewardship Science Academic Alliance through DOE Research Grants DE-FG52-07NA28058, DE-FG52-04NA00064. The software used in this work was in part developed by the DOE-supported ASC/Alliance Center for Astrophysical Thermonuclear Flashes at the University of Chicago.
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