Experimental investigation of side jet interaction with a supersonic cross flow

Stahl, Bernhard; Esch, Helmut; Gülhan, Ali

doi:10.1016/j.ast.2007.01.009

Cited by 41 publications

(44 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Compared to the wall pressure distributions presented in Fig. 13, the difference in the wall pressure distributions would tend to be slightly larger in the area in front of the jet and in the wake and, on the other hand, slightly smaller for the pressure distributions measured with the same momentum flux [21]. With the same thrust as the boundary condition, no differences can be detected from the wall pressure distributions recorded at the same jet pressure ratio.…”

Section: Wall Pressure Measurementsmentioning

confidence: 65%

Hot-Gas Side Jet in a Supersonic Freestream

Stahl

Siebe

Gülhan

2010

Journal of Spacecraft and Rockets

View full text Add to dashboard Cite

The present paper reports on the interaction of a hot side jet in a supersonic freestream and compares the effects with results from cold-gas jet investigations. With high-speed schlieren videos, a significant enlargement of the separation area has been ascertained upstream from the hot-gas jet and quantitatively confirmed with wall pressure measurements. The schlieren videos also show a strong oscillation of the separation and bow shock. By using an algorithm that analyzes the similarity of neighboring images, the oscillation frequency of the separation and bow shock has been measured to be 11.3 kHz. As a consequence of the dominant shocks in the area in front of the jet, the hot jet plume is screened off strongly from the freestream, thus resulting in an upstream inclination. Finally, highspeed videos have revealed large-scale structures in the hot-gas jet and their convection velocities have been analyzed. According to the shocks, the large-scale structures oscillate at 11.3 kHz. Jet oscillation is thus excited by the interaction of the hot-gas jet with the freestream and not by resonances from the combustion chamber. Nomenclature A J = jet exit area, m 2 C pdif = differential pressure coefficient, measured with and without jet flow D = diameter of the cylindrical part of model, mm d J = diameter of jet nozzle, mm d W = diameter of wind-tunnel nozzle, mm F = jet exit thrust, N I = jet exit momentum flux, N M J = Mach number of the side jet M 1 = Mach number of the freestream n = number of frames p = local pressure, bar p t = total pressure of the freestream, bar p tC = total pressure of cold-gas jet in the chamber, bar p tH = total pressure of hot-gas jet in the combustion chamber, bar p 1 = static pressure of the freestream, bar Re D = Reynolds number based on the model diameter D T JC = temperature of cold jet, K T JH = temperature of hot jet, K T tC = total temperature of the freestream and cold jet flow, K T 1 = static temperature of the freestream, K U c = convection velocity of jet flow, m s 1 U J = velocity of jet flow, m s 1 U 1 = velocity of freestream, m s 1 x = distance downstream from the model tip, mm z = direction of jet flow, mm = angle of attack, deg t = time between frames, s = angle of separation shock, deg ' = circumferential angle, deg = convection angle, deg = isentropic exponent = density, kg m 3 Subscripts J = jet exit condition JC = cold jet JH = hot jet t = static condition 1 = freestream

show abstract

Section: Wall Pressure Measurementsmentioning

confidence: 65%

Hot-Gas Side Jet in a Supersonic Freestream

Stahl

Siebe

Gülhan

2010

Journal of Spacecraft and Rockets

View full text Add to dashboard Cite

show abstract

“…The taps are positioned in four longitudinal sections at the circumferential angles ' 180, 150, 120, and 90 deg. A detailed description of the model is given in [19].…”

Section: B Pressure Measurementsmentioning

confidence: 99%

Experimental Study on Aerothermal Heating Caused by Jet-Hypersonic Crossflow Interaction

Gülhan

Schütte

Stahl

2008

Journal of Spacecraft and Rockets

View full text Add to dashboard Cite

The present paper reports on the results of an experimental study on aerothermodynamic effects associated with the injection of a lateral jet into a hypersonic crossflow around a generic missile model. This study intends to close the gap of missing reliable information on measured combined surface pressure and heat flux distribution on a missile configuration with a lateral jet. The model, consisting of a cone, cylindrical main body, and a flare, includes a single side jet hole. The model is made of a material with low thermal conductivity to visualize the surface temperature distribution, that is, heat fluxes. The surface temperature development on the model has been measured by infrared thermography. Using these data, the heat flux rate has been determined, taking into account temperature-dependent material characteristics, assuming a semi-infinite wall and the exchange of radiative cooling to the environment. Flow topology was analyzed using oil flow and schlieren images and wall pressure distribution measurements. The experimental data show that the jet pressure ratio has a significant effect on the side jet flow topology and its interaction with the crossflow. The influence of the angle of attack and the yaw angle on the pressure and heat flux distribution has also been measured clearly. Finally, the effect of various side jet gas media on the flow interaction has been demonstrated with tests using argon and helium as a jet gas complementary to air. Nomenclature a = thermal diffusivity, m 2 s 1 a = speed of sound, m s 1 C p = pressure coefficient c p = specific heat capacity at constant pressure, J g 1 K 1 D = diameter of the cylindrical part of model, mm d J = diameter of jet nozzle, mm M J = Mach number of the jet flow M 1 = Mach number of the external flow p = local pressure, bar p t = total pressure, bar p 0J = pitot pressure at the jet exit, bar p 1 = static pressure of the external flow, bar q = dynamic pressure, bar q conv = convective flux q L = conductive heat flux q rad = radiative heat flux Re = Reynolds number based on m 1 St = Stanton number T J = static temperature of jet flow, K T t = total temperature of crossflow, K T 1 = static temperature of the external flow, K t = time, s U 1 = velocity of external flow, m s 1 x, y = Cartesian coordinates z = thickness of polyether ether ketone material, mm = angle of incidence, respectively, heat-transmission coefficient therm = coefficient of linear thermal expansion, K 1 = angle of yaw " = emission coefficient = isentropic coefficient = thermal conductivity, W m 1 K 1 = density, kg m 3 B = Stefan-Boltzmann constant, J K 1 ' = circumferential angle Subscripts i = index (position) J = jet j = index (time) ref = reference value U = ambiance W = wall 0 = stagnation condition 1 = freestream

show abstract

“…In this work, the experimental condition of Stahl et al [16] is simulated numerically using a commercial software to understand the complex supersonic free stream and jet interaction problem for 1 jet, 2 jets, 3 jets positioned at different circumferential locations of an aerospace vehicle for various angle of incidence and pressure ratios. Detailed comparisons of experimental and computational surface pressure have been presented and various aerodynamic parameters are compared.…”

Section: Introductionmentioning

confidence: 99%