U.S Energy Secretary Steven Chu today announced the largest ever awards of the Department's supercomputing time to 57 innovative research projects. CCSE and collaborators earned two of these coveted awards.

The first award, titled "Simulation of Turbulent Lean Hydrogen Flames in High Pressure", with PI John Bell and Co-I Marc Day, was awarded 40 million hours. The second award, titled "Petascale Simulations of Type Ia Supernovae from Ignition to Observables", with PI Stan Woosley of UCSC and Co-I's John Bell and Mike Zingale of Stony Brook University, was awarded 50 million hours. The average allocation was 27 million hours.

"The Department of Energy's supercomputers provide an enormous competitive advantage for the United States," said Secretary Chu. "This is a great example of how investments in innovation can help lead the way to new industries, new jobs, and new opportunities for America to succeed in the global marketplace."

In 2006, when Yevgenii Rastigejev was a postdoc at Northwestern University, he used CCSE's IAMR code as the framework for a level set method he developed to study the nonlinear development of hydrodynamically unstable premixed flames.

Fast-forward a few years and Dr. Rastigejev is now Professor Rastigeyev, an assistant professor with a joint appointment in the Dept. of Mathematics and in Energy and Environmental Studies at North Carolina A&T State University. He, with his collaborator, Dr. Tang, have just been awarded a $1M HBCU-RISE grant by NSF to fund a three-year research mini-center, the Center for Advanced Multi-scale Computational Algorithms (AMCA).

A key part of the proposal involves using AMR methods for atmospheric chemical transport modeled by advection-diffusion-reaction equations. For this part, the new center will use an adaptive advection code developed by CCSE, and based on the common software framework shared by IAMR and CASTRO. In addition, CCSE will collaborate with the new center in the training of students on adaptive mesh methods for solving the advection/diffusion/reaction equations.

One is called "Supercomputers Dissect the Fiery Death Throes of a Dying Star to Understand the Origin of the Elements, Pulsars and Black Holes?"

The other is titled "Supercomputers Peer Into the Heart of a Flame to Help Scientists Build More Fuel-Efficient Burners."

What do they have in common?

The answer is CCSE.

These are two of the four colorful Computing Sciences postcards being given out at Berkeley Lab's SC10 booth. Each card features Department of Energy sponsored science results that were powered by NERSC supercomputers.

The supernova postcard shows results of a simulation performed by Jason Nordhaus and Adam Burrows at Princeton University using CCSE's CASTRO code.

The combustion postcard shows a simulation by CCSE's own Marc Day, John Bell and Mike Lijewski.

From iSGTW:

When large stars die out and collapse, they explode, creating a supernova. But when scientists attempted to simulate this process, they got a "fizzle" instead of a "bang." Until now, scientists simply assumed that there is something fundamental about the physics of supernovae that we didn't understand. Now scientists may have cracked the problem by using a new approach to create computer simulations of supernovae. "The new simulations are based on the idea that the collapsing star itself is not sphere-like, but distinctly asymmetrical and affected by a host of instabilities in the volatile mix surrounding its core" explained a recent press release. "Writing in the Sept. 1 issue of the Astrophysical Journal, Jason Nordhaus and Adam Burrows of Princeton University, and the Lawrence Berkeley National Laboratory's Ann Almgren and John Bell report that the new simulations are beginning to match the massive blow-outs astronomers have witnessed when gigantic stars die." Although jokes are often told about the physicist's propensity for assuming everything is a sphere, they do this with good reason: more complex models are costly to simulate, in terms of computational resources. This research was conducted on the National Energy Research Scientific Computing Center's Cray XT4 Franklin system, using CASTRO, a program developed by Almgren and Bell, and according to the press release, it wouldn't have been possible without access to a high performance computing facility. For more information, visit the original press release.

John Bell is giving an invited talk on Friday, October 29, at the Courant Institute of Mathematical Sciences in New York City. His talk is titled "Low Mach Number Models in Computational Astrophysics" and discusses work by Bell and others on developing and using a low Mach number model for astrophysical flows. For more information about the low Mach number model and the code based on it, see the MAESTRO page.

Two of seven stories on Computational Research for the Environment at LBL feature CCSE research. The first, titled "Carbon Goes Underground, Then What? 3-D Simulations Shed Light on Fate of Geologically Sequestered CO2", discusses research by George Pau and John Bell on carbon sequestration. The second, titled "Experiments and Simulations Join Forces to Engineer a New Type of Clean, Efficient Burner" discusses recent work by John Bell and Marc Day, in collaboration with Robert Cheng.

Most stars end their lives in a whimper - our own sun will almost certainly be one of them - but the most massive stars go out with an impressive bang. When that happens, creating what's known as a Type II supernova, the associated blast of energy is so brilliant that it can briefly outshine an entire galaxy, give birth to ultra-dense neutron stars or black holes, and forge atoms so heavy that even the Big Bang wasn't powerful enough to create them. If supernovas didn't exist, neither would gold, silver, platinum or uranium. The last time a supernova went off close enough to earth to be visible without a telescope, back in 1987, it made the cover of TIME.... more

For scientists, supernovae are true superstars -- massive explosions of huge, dying stars that shine light on the shape and fate of the universe. Recorded observations of supernovae stretch back thousands of years, but only in the past 50 years have researchers been able to attempt to understand what's really happening inside a supernova via computer modeling. These simulations, even crude ones, can lead to new information about the universe's size and eventual fate and help address longstanding problems in astrophysics.

Now, researchers from Princeton University and the Lawrence Berkeley National Laboratory have found a new way to make computer simulations of supernovae exploding in three dimensions. The new simulations are based on the idea that the collapsing star itself is not sphere-like, but distinctly asymmetrical and affected by a host of instabilities in the volatile mix surrounding its core.

Writing in the Sept. 1 issue of the Astrophysical Journal, Jason Nordhaus and Adam Burrows of Princeton University, and the Lawrence Berkeley National Laboratory's Ann Almgren and John Bell report that the new simulations are beginning to match the massive blow-outs astronomers have witnessed when gigantic stars die... more

Andy Aspden and Marc Day are presenting three papers at the 33rd International Symposium on Combustion being held in Beijing, China, August 1-6.

Aspden is presenting "Characterization of Low Lewis Number Flames" and "Lewis Number Effects in Distributed Flames", both co-authored with Marc Day and John Bell of CCSE.

Day is presenting "Numerical Simulation of Nitrogen Oxide Formation in Lean Premixed Turbulent Flames", co-authored with John Bell and Xinfeng Gao of CCSE, and Peter Glarborg of the Technical University of Denmark.

Marc Day and Ann Almgren gave presentations about their work on combustion and astrophysics to local high school students on Thursday, July 29, as part of an outreach program to introduce students to various career options in scientific computing and networking. The program was developed with input from computer science teachers at Berkeley High, Albany High, Kennedy High (in Richmond), and Oakland Tech.

John Bell presented two CCSE posters the SciDAC 2010 Conference held July 12-16, 2010, in Chattanooga, Tennessee. The posters were

• MAESTRO, CASTRO, and SEDONA: Petascale Codes for Astrophysical Applications,by Ann Almgren, John Bell, Mike Lijewski, Andy Nonaka, Peter Nugent, and Rollin Thomas of CRD; Daniel Kasen of UC Santa Cruz; Charles Rendleman of D. E. Shaw Research; and Michael Zingale of Stony Brook University
and
• Simulation of Nitrogen Emissions in a Low Swirl Burner,by John Bell, Marc Day, Xinfeng Gao, and Mike Lijewski of CRD

Deep inside a dying star in a galaxy far, far away, a carbon fusion flame ignites. Ignition may happen in the middle or displaced slightly to one side, but this simulation explores the consequences of central ignition. In a localized hot spot, represented here by a deformed sphere with an average radius of 100 km, carbon is assumed to have already fused to iron, producing hot ash (~10 billion K) with a density about 20% less than its surroundings. As the burning progresses, this hot buoyant ash rises up and interacts with cold fuel. Rayleigh-Taylor fingers give rise to shear and turbulence, which interacts with the flame, causing it to move faster. In about 2 seconds, the energy released blows the entire white dwarf star up, leaving nothing behind but a rapidly expanding cloud of radioactive nickel, iron, and other heavy elements. A Type Ia supernova is born.

George Pau presented a talk titled "High Resolution Simulation of Flows Encountered in Geologic CO2 Sequestration" at the Gordon-Kenan Research Seminar on Flow and Transport in Permeable Media held in Lewiston, Maine on July 10-11, 2010. He also presented a poster titled "Adaptive Mesh Refinement for Two-Phase Compressible Flow in Porous Media" at the Gordon Research Conference on Flow and Transport in Permeable Media held at the same location on July 11-16, 2010.

Alvarez Fellow Aleksandar Donev gave an invited talk in the minisymposium on Coarse-Grained Stochastic Models in Soft Condensed Matter on Sunday, May 23. His talk was titled, ``A Hybrid Particle-Continuum Method for Hydrodynamics of Complex Fluids,'' and discussed joint work with John Bell, Alejandro Garcia, and Berni Alder. Donev was also an organizer of the two-part minisymposium series.

Ann Almgren gave an invited talk in the Parallel Computing of Fluids and Interfaces minisymposium at the SIAM Conference on Parallel Processing and Scientific Compouting (PP10) meeting in Seattle on Thursday, February 25. Her talk was titled ``Parallel Adaptive Simulation of Low Mach Number Flows" and discussed joint work with John Bell, Andy Nonaka. and Mike Zingale.

Alvarez Fellow Aleksandar Donev gave an invited talk in the applied mathematics seminar at UC Berkeley on Thursday, February 4. His talk was titled, ``A Hybrid Particle-Continuum Method for Hydrodynamics of Complex Fluids,'' and discussed joint work with John Bell, Alejandro Garcia, and Berni Alder.

Alvarez Fellow Aleksandar Donev gave an invited talk in the applied mathematics seminar at UC Santa Barbara on Friday, Jan. 29. His talk was titled, ``A Hybrid Particle-Continuum Method for Hydrodynamics of Complex Fluids,'' and discussed joint work with John Bell, Alejandro Garcia, and Berni Alder.