Key Challenges: Developing accurate forecasts of the solar wind, an inherently turbulent process requiring simulation across a widely different scales of physics—from planet-size to the sub-atomic.
Why it Matters: When strong magnetic storms occur on the Sun, tons of highly energetic particles are released into the solar wind. If these particles were free to hit the Earth, the radiation would cause life-threatening damage to our DNA, debilitate power grids, disrupt communications networks and damage electronic devices.
Accomplishments: Simulations have managed to capture "cascades" of turbulence. a phenomenon common in fluid dynamics in which turbulent energy injected at large eddies is transported to successively smaller scales until it is dissipated as heat. For the first time scientists were able to visualize a current sheet in the solar wind, watch it form and evolve throughout its lifecycle. A current sheet is a region in the plasma where magnetic energy is stored and subsequently released.
NERSC Contribution: Visualizing the results required several new computational techniques that were developed by the NERSC Analytics Group to filter out noise in the data, to allow an existing visualization tool, called LIC, to run in parallel, and to speed up the visualization, allowing researchers to study the results in real-time.
Project Title: Petascale Kinetic Simulations in Laboratory and Space Plasmas
NERSC Resources Used: Hopper, Edison
DOE Program Office: FES - Fusion Base Program
Investigators: H. Karimabadi (UC. San Diego)
More Information: http://www.nersc.gov/news-publications/news/science-news/2013/supercomputers-capture-turbulence-in-the-solar-wind/ and a recent article in Physics of Plasmas.