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Prediction of Drag Reduction in Supersonic and Hypersonic Flows with Counterflow JetsComputational fluid dynamics solutions of the flowfield of a truncated cone-cylinder with and without counterflow jets have been obtained for the short penetration mode (SPM) and long penetration mode (LPM) of the freestream-counterflow jet interaction flowfield. For the case without the counterflow jet, the comparison of the normalized surface pressures showed very good agreement with experimental data. For the case with the SPM jet, the predicted surface pressures did not compare as well with the experimental data upstream of the expansion corner, while aft of the expansion corner, the comparison of the solution and the data is seen to give much better agreement. The difference in the prediction and the data could be due to the transient character of the jet penetration modes, possible effects of the plasma physics that are not accounted for here, or even the less likely effect of flow turbulence, etc. For the LPM jet computations, one-dimensional isentropic relations were used to derived the jet exit conditions in order to obtain the LPM solutions. The solution for the jet exit Mach number of 3 shows a jet penetration several times longer than that of the SPM, and therefore much weaker bow shock, with an attendant reduction in wave drag. The LPM jet is, in essence, seen to be a "pencil" of fluid, with much higher dynamic pressure, embedded in the oncoming supersonic or hypersonic freestream. The methodology for determining the conditions for the LPM jet could enable a practical approach for the design and application of counterflow LPM jets for the reduction of wave drag and heat flux, thus significantly enhancing the aerodynamic characteristics and aerothermal performance of supersonic and hypersonic vehicles. The solutions show that the qualitative flow structure is very well captured. The obtained results, therefore, suggest that counterflowing jets are viable candidate technology concepts that can be employed to give significant reductions in wave drag, heat flux, and other attendant aerodynamic benefits.
Document ID
20030014748
Acquisition Source
Marshall Space Flight Center
Document Type
Conference Paper
Authors
Daso, Endwell O.
(Boeing Phantom Works Long Beach, CA United States)
Beaulieu, Warren
(Boeing Phantom Works Long Beach, CA United States)
Hager, James O.
(Boeing Phantom Works Long Beach, CA United States)
Turner, James E.
Date Acquired
September 7, 2013
Publication Date
January 1, 2002
Subject Category
Aerodynamics
Report/Patent Number
AIAA Paper 2002-5115
Meeting Information
Meeting: AIAA/AAAF 11th International Space Planes and Hypersonic Systems and Technologies Conference
Location: Orleans
Country: France
Start Date: September 29, 2002
End Date: October 4, 2002
Sponsors: Association Aeronautique et Astronautique de France, American Inst. of Aeronautics and Astronautics
Distribution Limits
Public
Copyright
Public Use Permitted.
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