1. Center for Radiative Shock Hydrodynamics Fall 2011 Review
Introductory overview
R Paul Drake

2. You will see how our priorities have been driven by a sequence of integrated UQ studies
This first presentation
Motivation and introduction to the physical system
Overview of the past year and the project status
Our major accomplishments in this year
Simulation of the year-5 experiment (This presentation and more later)
Combining models of varying fidelity for UQ (Holloway and Bingham)
Completion of the laser package (Powell and Van der Holst talk)
Test experiments with nozzles and elliptical tubes (Kuranz)
Talks tomorrow and posters today provide many details
Organized abstract book provided for posters
Items in this color are directly responsive to 2010 recommendations

3. We find our motivation in astrophysical connections
Ensman & Burrows ApJ92
Radiative shocks have strong radiative energy transport that determines the shock structure
Exist throughout astrophysics
SN 1987A
Reighard PoP07
Talk less about scaling
Cataclysmic binary star
(see Krauland poster: but she is at a related experiment)

4. We are showing a visualization of CRASH 3.0 output on the TVs
This has “solved” the morphology conundrum
We can do runs that produce a wall shock but no protuberance
We still do have more to learn about running with our laser package and other issues that matter
Simulation details
0.8 µm effective resolution in 2D
Multigroup diffusion (30 groups, 0.1 eV to 20 keV)
5 materials, 2 AMR levels, CRASH EOS & Opacity
Also see scale models in the room
Movie should be showing

5. A brief primer on shock wave structure
Behind the shock, the faster sound waves connect the entire plasma
Denser,
Hotter
shocked
unshocked
Shock velocity, us
Initial plasma
Mach number M > 1
Mach number
M = us / csound

6. Shock waves become radiative when …
radiative energy flux would exceed incoming material energy flux
where post-shock temperature is proportional to us2.
Setting these fluxes equal gives a threshold velocity of km/s for our system:
Ts4 ∝ us ous3/2
unshocked
preheated
shocked
Material xenon gas
Density mg/cc
Initial shock velocity 200 km/s
Initial ion temperature 2 keV
Typ. radiation temp. 50 eV

7. CRASH builds on a basic experiment
Radiography is the primary diagnostic.
Additional data from other diagnostics.
A. Reighard et al. Phys. Plas. 2006, 2007
F. Doss, et al. Phys. Plas. 2009, HEDP 2010
Grid
Schematic of radiograph
See Kuranz talk

8. We’ve continued radiographic studies
Bayesian analysis of tilt gives compression ~ 22
Doss HEDP, A&SS 2010
Shock-shock interactions give local Mach number
Doss PoP 2009
Shape of entrained flow reveals wave-wave dynamics
Doss PoP 2011
Thin layer instability; scaling to supernova remnants
Doss thesis & to be pub.
3.5 ns
13 ns
Radiographs
26 ns
Credit:
Carolyn Kuranz

9. Also making or analyzing other measurements
Shock breakout from the Be disk
X-ray Thomson scattering
Papers in prep
Kuranz et al.
Stripling et al.
Visco et al.
Huntington et al.
See Kuranz talk and poster

10. CRASH 3.0 has substantial capability
Material & AMR
Laser package
Dynamic AMR
Level set interfaces
EOS
Self-consistent EOS and opacities for 5 materials
Use of other tables too
Multigroup-diffusion radiation transport
Electron physics and flux-limited electron heat conduction
Log Density
Log Electron Temperature
Log Ion Temperature
3D Nozzle to 13 ns

11. We’ve completed simulations of the year-5 experiment
Shock at 13ns in Elliptical Tube
This is the system we want to predict
Elliptical simulations
(H2D initiated):
Van der Holst et al, HEDP
Submitted 2011
Show movie 2 once through, then movie 3
Bart’s movie is 1.6 µm effective resolution, H2D initialized, MG
Cassini oval (movie 3 is 1 µm resolution, H2D initialized, gray)
13 ns multigroup

12. Our “viewgraph norms” are a lot better than they were
600 µm 1200 µm Circular Elliptical tube tube nozzle nozzle
26 ns gray
Switch from movie 3 to movie 4
Although things are not perfect, we are ready to proceed beyond viewgraph norms to serious predictive studies.
13 ns MG

13. We have accomplished a lot during the past year
Code improvements
Laser package
EOS source increased adaptivity
Progress on multigroup preconditioner
Hydro scaling
PDT scaling
Implicit scaling with HYPRE
Non-LTE
Physics
More papers
Obtaining STA opacities
Work on non-LTE effects
SN/FLD comparison
Experiments
Early time radiographs
Deeper analysis of shock breakout
Year 4 experiments: large tubes, nozzles, first elliptical results
Progress on X-ray Thomson scattering
UQ and predictive studies
Predictive method involving joint models
Predictive study with joint models and calibration/tuning
First run set with laser package
Evaluation of AMR fidelity
Evaluation of sensitivity to opacity
Code comparison project
Steady though slow work on hydro validation
Routine parallel scaling tests
CRASH 3.0 released; CRASH used
Base CRASH problem
Elliptical tube
Application to other experiments
Hydro instability studies …
Items in this color are directly responsive to 2010 review

14. We are organized and managed for success
Strategic allocation of resources with tactical reallocation based on weekly meetings
Ability to accomplish and improve our UQ work drives these decisions
Some examples: focus on laser package, timestep controls, convergence
We are managing around the UCNI problem
Regular meetings of specific groups
UQ, Applications, Software, Graduate students, Hydro
Education items
Having CRASH session and lunch/posters at APS/DPP to increase interactions with NNSA lab personnel and better disseminate CRASH developments
Continuing to work with and recruit new students
Continuing our educational programs in predictive science

15. There are areas in which we have not addressed prior recommendations
Mostly this reflects following the recommendation to allocate resources strategically
A list
Lines of code coverage analysis
Solution verification as distinct from the verification we have reported
Computer bandwidth to the labs remains an issue
It has improved by a large factor at LLNL
PDT validation
Management/Education
Attempt to tightly coordinate students time at labs
In some areas where we have made progress, resource allocation has limited our progress

16. We are in the age of run sets
A substantial fraction of our activity
Defining
Initiating via a formal process
Running (as platforms change)
Processing
Analyzing
Reacting
Many people & interactions
RS 4: 104 2D on base expt
RS 5: 512 1D on numerics
RS 6: 128 2D on numerics
RS 7: for nozzles
The final H2D runset (ugh!)
RS 8: 27 2D Nozzle properties
RS 9: 10 3D Ellipticity and shape
RS 10: 128 2D base CRASH
With laser package
Future run sets discussed later
Put up number 5: RS10_13 ns_cleanwide
H2D could not get the job done

17. We’ve been burning up the cycles
Running queue-limited much of the time
Also burning a few x 100,000 core hours per month here at UM
We’d crank up the output this next year if we were not limited by cycles, queues, and data transport
H2D
Core hours

18. Our predictive studies include a main path and supporting activities
A sequence of studies that let us apply the joint model methodology to predict the year 5 experiment (see next talk)
Supporting activities
Solid verification practices
Small studies focused on specific issues
AMR, opacity impact, exact shape of 3D experiment, etc
Validation and code comparison studies (see Fryxell talk)
We are ready to make temperature measurements
For the CRASH system
From heat waves for validation (Gamboa poster)
request review committee endorsement of this

19. Our roadmap for prediction is now based on 2D & 3D CRASH
Newly completed RS 10 Multigroup (MG) is the foundation going forward (120 runs, 6360 observations)
Expect to show improved prediction over last year
May need to redo as laser package use matures
11/2011 – 1/2012: Complete RS10 Gray (G); combine G and MG to predict SL (shock location) & WSA (wall shock angle)
2/12 – 3/12: RS 11 – 2D G & MG with Nozzle
2/12 – 5/12: RS 12 – 3D Gray with Oval tube; construct predictive model for SL & WSA; select best next points to compute
6/12 – 7/12: RS 13 based on RS10 – 12; construct predictive model for SL & WSA

20. We are moving forward to complete the project
Our code is of sufficient quality
The laser package is the final key development
We have demonstrated that we can do the necessary run sets
We have done a run set with the laser package
We have developed the methods to assess predictive capability
We are ready to apply them to the year 5 experiment
Our experiments are in a position to test our predictive capability and expand our validation data

21. Supplemental material follows

24. Our experimental sequence will improve and test our assessment of predictive capability
A conceptually simple experiment
Launch a Be plasma down a shock tube at ~ 200 km/s
Year 5 experiment
Predict outcome and accuracy before doing year 5 experiment
Goals
Improve predictive accuracy during project
Demonstrate a predictive uncertainty comparable to the observed experimental variability
A big challenge and achievement

25. We’ve invested real effort in scaling
CRASH hydro on BG/L
PDT transport on BG/L
Weak scaling