The picture shows a Direct Numerical Simulation of a Mach 1.92 jet. The jet turbulence
is visualized with contours of vorticity magnitude and the near acoustic field is visualized with gray levels indicating
divergence of velocity, which highlights the weak shocks (dark) and relatively broad expansions (light).
Contributed by Prof. Jonathan B. Freund, University of Illinois at
Urbana-Champaign.
Reference: J. B. Freund, S. K. Lele, and P. Moin. "Direct numerical simulation of a Mach 1.92 turbulent
jet and its sound field," AIAA J., 38(11), 2023--2031, (2000).
