Effect of the plenum-chamber diameter on the turbulent characteristics of a supersonic jet

Free underexpanded jets in a quiescent medium: A review

“…Their size is of the order of the boundary-layer thickness but increases downstream and with the pressure ratio [157,152,179,165,166,181]. Furthermore, these disturbances tend to amplify initial perturbations due to the nozzle boundary layer or to some features of the nozzle walls, such as the roughness of their inner side that can be connected to the streamwise vortex structures [151,160,162,152,167,169].…”

“…Thus, the only papers providing quantitative results for the length of the potential core [30,156] [30,65,59,135,[157][158][159][160][161][162][163][164][165][166][167][168][169][170][171][172][173][174]149,122,61,94] yet some numerical papers are also available [37,59,122,[175][176][177][178][179][180][181]. These structures play a major and significant role in the behavior of the jet, especially in its spreading rate and the associated decay, because of their interaction with the various shock waves [134,38,158,156,164,52,149,178,166,171]<...>…”

“…Contrary to what happens in the core of the jet, the viscous effects have here a tremendous influence, particularly because of their impact on the development of the flow instabilities and consequently on the width of the mixing layer and on the diameter of the jet. This has been formalized by [69], and confirmed by [163,152,162], who defined an initial Reynolds number Re i for the shear layer, based on the exit velocity and the distance to the Mach disk and the viscosity of the ambient fluid, such that for…”