Density gradient magnitude reproduced by large eddy simulation of an under expanded air jet issued from a circular nozzle with an exit diameter of 12.7 mm and a pressure ratio of 5. Prandtl-Meyer expansion fans, Mach reflection, annular shear layers, propagating pressure waves, shocklets-shear interactions and turbulent mixing are visualised.
Shock and turbulence structures in an under-expanded jet —

Density gradient magnitude reproduced by large eddy simulation of an under expanded air jet issued from a circular nozzle with an exit diameter of 12.7 mm and a pressure ratio of 5. Prandtl-Meyer expansion fans, Mach reflection, annular shear layers, propagating pressure waves, shocklets-shear interactions and turbulent mixing are visualised.

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