In this talk, we will concentrate on the singular properties of compressible turbulence. One is the degeneracy of the sum of Lyapunov exponents. That is non-zero for a general chaotic compressible flow but vanishes for compressible turbulence. Another is the continuous transition in the direction of the cascade of energy that occurs in two-dimensional compressible flow as compressibility increases from zero. At small compressibility the energy cascades to large scales, however at larger compressibility it tends to go to small scales. Finally, we demonstrate that even slight compressibility could lead to the enhancement of seed magnetic fields, which is forbidden for strictly incompressible flows.
Bio: Itzhak Fouxon has Ph. D from Weizmann Institute of Science in turbulence and complex systems. Itzhak worked in turbulence in Newtonian fluids and polymer solutions, both incompressible and compressible, in magnetohydrodynamics and general smooth systems, in low-Reynolds number hydrodynamics and swimming of microorganisms, in black holes (with discover of black hole entropy J. Bekenstein), in linear and non-linear geophysical waves, turbulent transport of tracers and inertial particles with emphasis on multifractal properties, and more. Itzhak is currently a researcher at Ben-Gurion University of the Negev in Israel.