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Two figures are shown: Pressure dependence of the shear modulus of Ta for two fundamental curves: the 300 K isotherm and the Hugoniot; and, Scaling of the high pressure strength (Y) of Ta with shear modulus (G). The dashed curve represents a hypothetical G which is fit such that the linear scaling approximation matches the data.
Various graphs are included for Progress Report 1 for the project.
Abstract not provided.
We requested HPC support to continue research on the seismic waves generated by impacts. We used the following codes: (1) the Hybrid Optimization Software Suite (HOSS), developed at LANL. HOSS is based on a combined Finite and Discrete Element Method (FDEM). New material models are developed for the sedimentary rocks. HOSS has been recently benchmarked to iSale and FLAG codes. SPECFEM3D is an open-source code developed since the last 90s. It won the Gordon Bell award for best performance in 2003, was finalist again in 2008 for a run at 0.16 petaflops on 149,784 cores on the ‘Jaguar’ Cray system at Oak Ridge National Laboratory. It also won the BULL Joseph Fourier supercomputing award in 2010.; SW4 is a 4th-order finite difference code developed at LLNL which is currently actively developed to handle complex 3D models and to be ported on future exascale platforms. We assessed our need to a total of 3.9M CPU-hrs for year 1 and and 3.1 M for year 2.
Maud Rise and Weddell Sea polynyas in the Southern Ocean form because of a series of feedbacks between upper ocean high salinity anomalies, Taylor columns found near steep bathymetric features such the Maud Rise seamounts and the Astrid Ridge complex, and subsurface accumulation of ocean heat that can sustain ice openings once deep convection is triggered.
Abstract not provided.
We’ve achieved our technical goals: (1) Perform large-scale kinetic simulations of SRS and CBET a range of plasma and laser conditions; (2) Develop a new $\delta f$-Gaussian-mixture algorithm to represent non-Maxwellian distribution functions from particle trapping and time-dependent plasma response; (3) Develop physics-based preliminary nonlinear LPI models for coupling to LRT/ Mazinisin and AMP; and (4) Begin implementation of LPI sub-grid models into Mazinisin.
Here we show that cross-beam energy transfer (CBET) saturates through a resonance detuning that depends on the IAW phase velocity and that results from trapping-induced modifications to the ion distribution functions. For smaller phase velocities, the modifications to the distribution functions can rapidly thermalize in the presence of mid-Z ions, leading to a blueshift in the resonant frequency. For larger velocities, the modifications can persist, leading to a redshift in the resonant frequency.
Large-scale simulations were conducted using the computational tool HOSS to investigate scientific aspects of the time reversal process. The main focus was the identification of damage/defects in wellbores for relevant subsurface applications.
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During FY20, approximately 20 TB of data were transferred from Test Bed 1 (TB1) to the LANL HPC DTN via Globus, consisting of over 3 million individual data files in a variety of formats (i.e., TIFF, JPEG, TDMS, WAV, and AVI). Data transfer rates of 250MB/s up to 500MB/s were routinely acheivable.
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