Researchers at the University of Illinois Urbana-Champaign have made a significant breakthrough in understanding the turbulent behavior of hypersonic flows. Using advanced 3D simulations, they discovered unexpected instabilities and flow breaks around cone-shaped models at Mach 16, which could significantly impact the design of future hypersonic vehicles.
At these extreme speeds, air behaves in complex ways as it interacts with a vehicle’s surface, forming features like boundary layers and shock waves. The researchers used high-resolution 3D simulations on a leadership-class supercomputer to study this phenomenon. This work was made possible by access to Frontera, a supercomputer funded by the National Science Foundation, and specialized software developed by Professor Deborah Levin’s former graduate students.
The study found that even at Mach 16, where air molecules are more viscous, the flow around the cone shape exhibits breaks in the flow within shock layers. These breaks occur near the tip of the cone and are promoted by the shock wave getting closer to the surface as the speed increases.
The researchers used a new simulation technique called direct simulation Monte Carlo (DSMC) to track individual air molecules and capture collisions with other particles or solid surfaces. This method provides more accurate results than traditional computational fluid dynamics methods, which rely on deterministic calculations.
This breakthrough could lead to improved design considerations for hypersonic vehicles by understanding how extreme speeds interact with surface geometries in new ways. The study’s findings will be published in Physical Review Fluids and are available online.
Source: https://scitechdaily.com/mach-16-mayhem-supercomputer-uncovers-chaos-in-hypersonic-flows