Inexpensive car-crash simulations that capture the same information as an actual car crash have been performed in a few days to a few weeks on supercomputers. However, at the Department of Energy's (DOE) Oak Ridge National Laboratory (ORNL), a car crash can be simulated and analyzed on the Intel Paragon XP/S supercomputer in a much shorter time - only eight hours - and at a lower cost. The ORNL supercomputer consists of 512 parallel processors that can work on many parts of the same problem at the same time.
"Using data supplied by the U.S. Department of Transportation, we have done a half-day analysis of a four-door sedan crashing into a lamppost at 35 miles per hour and of a head-on collision between two cars," says Thomas Zacharia, a group leader in ORNL's Metals and Ceramics Division. He first used this approach to simulate the impacts of hypothetical transportation accidents on waste shipping containers.
Zacharia is currently serving as acting director of the new Computational Center for Industrial Innovation in ORNL's Center for Computational Sciences (CCS). This new center will be a focal point for ORNL's interaction with industry on high-performance computing.
Zacharia is also ORNL's representative to the Supercomputing for Automotive Applications Partnership (SCAAP) of the U.S. Consortium on Automotive Research (USCAR). Other representatives on this committee are from Chrysler, Ford, General Motors, and from Argonne, Lawrence Livermore, Los Alamos, and Sandia national laboratories.
USCAR is one of the chief participants in the Clean Car Initiative announced by President Clinton in 1993. The goal of this initiative is to design new cars that emit less pollution and are safer and more efficient than current vehicles.
"ORNL is a leader in using massively parallel supercomputing both for simulating car crashes and modeling materials and for manufacturing processes for cars," Zacharia says. "The information generated can be used to analyze the efficiency and safety of new car designs for the automotive industry."
Zacharia, who came to ORNL seven years ago to do process modeling, first used parallel computers to model the impacts of dropping or crushing a radioactive waste container during a truck or train crash. Zacharia then showed that the same code could be used to simulate the results of car crashes.
In car-crash analyses at ORNL, the processors calculate the local deformation and energy absorbed during a car crash for each of 56,000 points, or finite elements. These include 3,000 spot welds as well as 248 different structural materials. Zacharia, his research group, and Ross Toedte of the CCS Visualization Laboratory at ORNL have produced colorful still and animated images of smashed cars, showing the dramatic impacts of collisions.
Zacharia says he and scientists from other DOE national laboratories are working on developing the next-generation computer codes for car-crash analysis and engine combustion analysis.
This work is being supported by the Basic Energy Sciences section of DOE's Office of Energy Research.
ORNL, one of the DOE's multiprogram research laboratories, is managed by Martin Marietta Energy Systems, which also manages the Oak Ridge K-25 Site and the Oak Ridge Y-12 Plant.