Hokkaido University and RIKEN AICS are researching aerodynamics simulation, to simulate the air flow around automobiles. Investigating the force exerted by air on a moving car is essential for improving fuel efficiency and safety. In particular, using a supercomputer called K has made it possible to simulate air resistance, which is the most important factor, with a precision equivalent to wind tunnel tests.
The fluid simulations currently done by automakers use up to a hundred million cells around the vehicle. By contrast, simulations on the K computer use up to 20 billion cells. Compared with conventional simulations, this achieves tens of times higher resolution. Also, creating the computational model, or lattice, used in large-scale simulations had been a big issue. But in ultra-large-scale analysis using the K computer, careful attention to how the lattice is defined makes simulation at least 100 times faster. Through such new methods of analysis, using the K computer has reduced the margin of error in air resistance prediction from about 5% to 2%. Such high-precision air resistance prediction will be a great help in developing cars with even higher fuel efficiency.
Some of this research on aerodynamics simulation is being done by a consortium, including 13 Japanese automakers and related companies, and four research institutes. From now on, the research will take account of needs in Japanese industries, with the aim of transferring technology to the automotive industry.