the nasa hpcc ess cooperative agreement pi: andrea malagoli
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Turbulent Convection and Dynamos in Stars. The NASA HPCC ESS Cooperative Agreement PI: Andrea Malagoli. Co-Investigators Nic Brummell Fausto Cattaneo Tom Clune Anshu Dubey Bill Gropp Rusty Lusk David Porter Robert Rosner Rick Stevens Juri Toomre Paul Woodward. NASA/GSFC. - PowerPoint PPT PresentationTRANSCRIPT
The NASA HPCC ESS Cooperative AgreementThe NASA HPCC ESS Cooperative Agreement
PI: Andrea MalagoliPI: Andrea Malagoli
University of Chicago/ANL University of Colorado University of Minnesota
Co-InvestigatorsNic Brummell
Fausto CattaneoTom Clune
Anshu DubeyBill Gropp
Rusty LuskDavid Porter
Robert RosnerRick StevensJuri Toomre
Paul Woodward
Turbulent Convection and Dynamos in StarsTurbulent Convection and Dynamos in Stars
NASA/GSFC
MHD-PPM Convection (MHD-PPMC): 195.8 GFlops• The Piecewise Parabolic Method coupled with a parabolic solver.• Solves the equations of compressible (magneto)hydrodynamics (MHD) with radiative diffusion.
Hybrid PseudoSpectral (HPS): 167.0 GFlops• Uses hybrid finite-difference and pseudospectral spatial derivatives
and a second order time stepping method.• Solves the equations of compressible (magneto)hydrodynamics (MHD) in a rotating plane.
MHD PseudoSpectral (MPS): 160.0 GFlops• Uses a fully pseudospectral method with Runge-Kutta time stepping.• Solves the equations of incompressible (magneto)hydrodynamics (MHD) in a triply periodic domain.
Turbulent Convection and Dynamos in Stars: Performance Milestones[PI: Andrea Malagoli - University of Chicago]
All our Scientific Application codes have achieved the 100 GigaFlops performance milestone on the Cray
T3E-1200 testbed at NASA/GSFC
Observations data obtained by current NASA missionsreveal that complex, highly time dependent phenomena are taking place on the surface of the Sun.
These phenomena are related to the vigorous interaction between turbulence, rotation and magnetic fields in the Sun’s Interior.
Simulation-based models on NASA’s High Performance Testbeds are used to interpret observations data and to build detailed models of the Sun’s interior.
These models play a fundamental role in both the interpretation of current missions data and in driving the design of all future missions
The 11-years Cycle
Magnetograms
H images
Model of the Sun’s Interior
Prominences
HelioSeismology
Granulation and Sunspots
X-ray images
The NASA HPCC ESS CAN Turbulent Convection and Dynamos in Stars
PI: Andrea MalagoliFrom Missions Data to Modeling the SunFrom Missions Data to Modeling the Sun
YOHKOH SOLAR BSOLAR PROBETRACESOHO
Turbulent Convection and Dynamos in Stars: Simulations[PI: Andrea Malagoli - University of Chicago]
Convectively driven solar dynamo simulations have been carried out using our Milestones codes on NASA’s T3E testbed.
AUTHORS: Fausto Cattaneo and Anshu Dubey - UofC
MACHINE: Cray T3E-1200 at NASA/GSFC
CODE: MHD PseudoSpectral
RESOLUTION: 512x512x97
Temperature
Temperature fluctuations near the upper boundary in a numerical simulation of convectively driven dynamo action. Dark tones correspond to cold (downflowing) material
Vertical magnetic field
Vertical component of the magnetic field near the upper boundary. Dark and light tones correspond to fields of opposite polarity
High resolution simulations are used to study the origin of magnetic fields in the quiet photosphere of the Sun
Images from the simulations can be compared with observational images
The model suggests that small flux elements are generated locally by dynamo action associated with the granular and supergranular flows
Turbulent Convection and Dynamos in Stars: Simulations[PI: Andrea Malagoli - University of Chicago]
AUTHORS: Fausto Cattaneo and Anshu Dubey
MACHINE: Cray T3E-1200 at NASA/GSFC
CODE: MHD PseudoSpectral
RESOLUTION: 512x512x97
Original Coarse grained
Detail of bipolar magnetic element. The figure shows an area of 200x200 pixels.
Same image convoluted with a Gaussian filter with 12 pixels FWHM.
Simulation data have higher resolution than observational data. Artificial blurring can be used to compare and interpret observational data
Simulations by F. Cattaneo & A. Dubey
Numerical simulations of convectively driven dynamos
orig
inal
coar
se g
rain
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• Magnetic elements generated by dynamo action display considerable structural complexity• Limited resolution can lead misleading interpretation of true structure of magnetic elements in terms of oversimplified flux tube models• Numerical simulation can help the development of more realistic models and the design of high resolution instruments for the detection of small-scale magnetic elements
Detail of bipolar magnetic element. The figure shows an area of 200x200 pixels.
Same image convoluted with a Gaussian filter with 12 pixels FWHM. Even a modest amount of coarse graining leads to substantial loss of information.