Effects of swirl and high turbulence on a jet in a crossflow

Kavsaoğlu, Mehmet S.
Schetz, Joseph A.
An experimental study has been conducted on the effects of initial swirl and high turbulence in the exhaust of a circular jet injected from a flat plate at a 90-deg angle into a crossflow. The different jet types studied were low-exit turbulence (3%), high-exit turbulence (>10°7o), and 40 and 58% swirl. Surface pressure distributions and mean velocity vector plots were obtained for all of these cases. For the surface pressure distribution tests, the jet to crossflow velocity ratios R were 2.2, 4, and 8 for most of the jet types. For the mean velocity vector plots, R = 4 was chosen. Turbulence information in the jet plume was also obtained for the low-exit turbulence case at R = 4. The results showed that the higher-exit turbulence reduced the penetration height, and it also reduced the surface area influenced by negative pressures. The swirl-caused asymmetric pressure distributions and the swirl effects were more pronounced for lower-velocity ratios.
Journal of Aircraft


Rectangular jets in a crossflow
Kavasoğlu, Mehmet S.; Schetz, Joseph A.; Jakubowski, Artur K. (American Institute of Aeronautics and Astronautics (AIAA), 1989-9)
Rectangular jets injected from a flat plate into a crossflow at large angles have been studied. Results were obtained as surface pressure distributions, mean velocity vector plots, turbulence intensities, and Reynolds stresses in the jet plume. The length-to-width ratio of the jets was 4, and the jets were aligned streamwise as single and side-by-side dual jets. The jet injection angles were 90 and 60 deg. Surface pressure distribution results were obtined for jet-to-freestream velocity ratios of 2.2, 4, a...
Effect of Thickness-to-Chord Ratio on Flow Structure of a Low Swept Delta Wing
Gulsacan, Burak; Sencan, Gizem; Yavuz, Mehmet Metin (American Institute of Aeronautics and Astronautics (AIAA), 2018-12-01)
The effect of thickness-to-chord (t/C) ratio on flow structure of a delta wing with sweep angle of 35 deg is characterized in a low-speed wind tunnel using laser-illuminated smoke visualization, particle image velocimetry, and surface pressure measurements. Four different t/C ratios varying from 4.75 to 19% are tested at angles of attack, 4, 6, 8, and 10 deg, for Reynolds numbers Re =1 x 10(4) and 3.5 x 10(4). The results indicate that the effect of thicknessto-chord ratio on flow structure is quite substan...
Investigation of rotor wake interactions in helicopters using 3d unsteady free vortex wake methodology
Yemenici, Öznur; Uzol, Oğuz; Department of Aerospace Engineering (2010)
This thesis focuses on developing and examining the capabilities of a new in-house aerodynamic analysis tool, AeroSIM+, and investigating rotor-rotor aerodynamic interactions for two helicopters, one behind the other in forward flight. AeroSIM+ is a 3-D unsteady vortex panel method potential flow solver based on a free vortex wake methodology. Validation of the results with the experimental data is performed using the Caradonna-Tung hovering rotor test case. AeroSIM+ code is improved for forward flight cond...
Simulation of Rapidly Maneuvering Airfoils with Synthetic Jet Actuators
Jee, SolKeun; Lopez Mejia, Omar D.; Moser, Robert D.; Muse, Jonathan A.; Kutay, Ali Türker; Calise, Anthony J. (American Institute of Aeronautics and Astronautics (AIAA), 2013-08-01)
Synthetic jet actuators are investigated for rapidly maneuvering airfoils that are regulated by a closed-loop control system. To support active flow-control simulations performed here, the closed-loop system and vehicle dynamics are coupled with computational fluid dynamics. High-frequency sinusoidal pitching simulations with and without synthetic jet actuation indicate that the current synthetic jet actuators provide bidirectional change in aerodynamic forces during rapid maneuvers whose time scales are of...
Near-surface topology and flow structure on a delta wing
Yavuz, Mehmet Metin; Rockwell, D (American Institute of Aeronautics and Astronautics (AIAA), 2004-02-01)
The streamlines, and the corresponding patterns of velocity and vorticity, are characterized on a plane immediately adjacent to the surface of a delta wing using a laser-based technique of high-image-density particle image velocimetry. This technique provides the sequence of instantaneous states, as well as the corresponding time-averaged state, of the near-surface streamline topology and the associated critical points. These topological features are interpreted in terms of patterns of averaged and unsteady...
Citation Formats
M. S. Kavsaoğlu and J. A. Schetz, “Effects of swirl and high turbulence on a jet in a crossflow,” Journal of Aircraft, pp. 539–546, 1989, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/51703.