Print Email Facebook Twitter Experimental Investigation of Transverse Jet Injection into Supersonic Crossflow Title Experimental Investigation of Transverse Jet Injection into Supersonic Crossflow Author Pazhev, Ventsislav (TU Delft Aerospace Engineering) Contributor Schrijer, F.F.J. (mentor) van Oudheusden, B.W. (mentor) Degree granting institution Delft University of Technology Programme Aerospace Engineering Date 2020-11-06 Abstract Transverse jet injection into supersonic crossflows is encountered with Aerospace applications such as fuel injection in Supersonic Combustion Ramjet (SCRamjet) engines and reaction-jet-based attitude control systems. In particular, for the case of SCRamjets, the short residence times of the fuel in the combustion chamber can be countered by the rapid mixing process in the near field of transverse jet injection. Research in the field focused on the development of jet trajectory correlations and the characterisation of the flow large-scale structures through, predominantly, flow visualisations and numerical simulations. The advent of full-field, quantitative experimental techniques has brought more insight into the jet behaviour in the interaction far-field. However, there is a scarcity of full-field quantitative experimental data in the near field of the injection. This study investigates the effect of a set of major flow control variables on the near and mid-field of the interaction by performing experimental measurements of transverse jets injected into a Mach 2 crossflow. To achieve this, the techniques of Schlieren imaging and Particle Image Velocimetry (PIV) are used in tandem. The PIV setup consisted of a dual-camera layout, which made it possible to obtain 2-dimensional mid-plane velocity vector maps in the range up to 17 diameters. During the investigation, the jet Mach number and the jet-to-crossflow momentum flux ratio were varied. The obtained Schlieren images and PIV vector fields displayed the characteristic interaction and jet shock structures, including the bow and boundary layer separation shock, the jet barrel shock and Mach disc. The location strength and width of the jet wake and the counter-rotating vortex pair (CVP) formed aft of the injection were indicated by the streamwise and vertical velocity, respectively. Increase in the jet-to-crossflow momentum flux ratio led to increase in the near field jet penetration and blockage, causing a stronger bow shock and larger separation. Turbulence intensity contours and velocity deficit and vertical velocity profiles also show an increase in the wake and CVP upwash strength and penetration. Variation of the jet Mach number was found to affect the flow field significantly. Switching from sonic to supersonic injection caused less blockage near field, yet similar penetration was seen in the mid-field. The formation of the characteristic CVP seemed to be delayed, and the extent and strength of the turbulent structures were smaller as compared to the sonic injection case. Subject SupersonicJetTurbulenceSCRamjetCrossflowParticle Image Velocimetry (PIV)SchlierenmixingtrajectoryNozzles To reference this document use: http://resolver.tudelft.nl/uuid:3dfd72bf-9b4a-4f98-9f95-9f610a466e57 Embargo date 2020-12-31 Part of collection Student theses Document type master thesis Rights © 2020 Ventsislav Pazhev Files PDF MSc_Thesis_VPAzhev_1.pdf 17.22 MB Close viewer /islandora/object/uuid:3dfd72bf-9b4a-4f98-9f95-9f610a466e57/datastream/OBJ/view