Large Eddy Simulation of Fluidic Injection into a Supersonic Convergent-Divergent Duct

Authors: Semlitsch, B., Fuchs, L.F., Mihaescu, M
Document Type: Article
Pubstate: Published
Journal: Direct and Large-Eddy Simulation 9 (DLES-9)
Volume: 20, Springer   297-302
Year: 2015


Convergent-divergent (C-D) ducts operating in supersonic flow-regimes provoke choked flow conditions in the region of the narrowest cross-section. The developed internal shocks can be unwanted for various reasons, e.g. the associate pressure losses. Fluidic injection onto the exhaust of a gas turbine engine or internal fluidic injection in ducts or nozzles have been performed for various reasons, e.g. improvement of mixing, noise reduction, performance improvement, cooling, or thrust vectoring. The effect of injection was observed to depend highly on the location of injection, injection pressure, duct pressure, and inclination angle. The present study investigates the behaviour of the shock-pattern inside a C-D duct, without and with fluidics. The effect of circumferential injection into the divergent part of the C-D duct is analysed. The main focus is on the transformability and the control of the shock-pattern in the duct and the disruption of the quasi-static shock-structure, with the purpose of decreasing the occurring losses in the duct.