Results 101 to 110 of about 2,285 (153)

Application of a Blowdown Wind Tunnel for Liugc- Scale Acoustic Environmental Testing

Journal of Occupational and Environmental Medicine, 1961
A unique application of a blowdown wind tunnel for intense noise testing of large components or of entire vehicles will be described. The above facility, which is primarily used for thermal structures testing, has a 12-ft diam exhaust jet which generates an extensive noise field useful for test purposes.
William H. Mayes, Philip M. Edge
openaire   +1 more source

Applications of infrared thermography in a hypersonic blowdown wind tunnel

International Congress on Instrumentation in Aerospace Simulation Facilitie, 2003
The authors describe special applications of infrared imaging for the measurement of the surface temperature distribution on models exposed to a hypersonic flow field. A number of infrared images are shown, which demonstrate the advantages and limitations of this measurement technique. In connection with image processing of an IBM computer the infrared
A. Henckels, F. Maurer
openaire   +1 more source

Stagnation Pressure Transient Control in a Supersonic Blowdown Wind Tunnel Test Facility

Materials Today: Proceedings, 2016
Abstract Research in the area of wind tunnel flow parameters control has been intensified in recent years, in an attempt to improve quality and efficiency of the wind tunnel operation. In this paper, stagnation pressure transient control in a supersonic blowdown-type wind tunnel is considered, with the aim of increasing available measurement time and
Ilić, Biljana, Milosavljević, Mirko, Isaković, Jovan, Miloš, Marko   +3 more
openaire   +2 more sources

Modification of a Transonic Blowdown Wind Tunnel to Produce Oscillating Freestream Mach Number

48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition, 2010
This paper details the design, construction, and evaluation of a modification to Ohio State’s 6” × 22” Transonic Wind Tunnel to enable modulation of the freestream Mach number. The test section Mach number in this blowdown facility is dynamically set by varying the choke area in a harmonic fashion.
Kyle Gompertz, Christopher Jensen, Pradeep Kumar, Di Peng, James W. Gregory, Jeffrey P. Bons   +5 more
openaire   +1 more source

Diagnostic simulation of a pneumatically controlled blowdown wind tunnel

SIMULATION, 1973
The nonlinear differential equations required to correctly model the plenum pressure history of a pneumatically controlled blowdown wind tunnel are derived,and arguments in favor of digital simulation of the full nonlinear equations as opposed to conven tional linearized analysis are presented.
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Prediction of internal and external noise fields for blowdown wind tunnels

Society of Naval Architects and Marine Engineers, and U.S. Navy, Advanced Marine Vehicles Meeting, 1972
Empirical methods have been developed to estimate the test section noise levels and the outside noise radiation patterns of blowdown wind tunnels. Included are considerations of noise generation by control valves, burners, turbulent boundary layers, and exhaust jets as appropriate.
R. HOSIER, W. MAYES
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Methods for investigating supersonic ground effect in a blowdown wind tunnel

Shock Waves, 2008
Two methods to experimentally investigate supersonic ground effect problems in a wind tunnel have been examined to determine their relative effectiveness compared to a more realistic, but physically unfeasible, representation of the ground effect by means of a moving ground. Experimental data were compared with the results of numerical simulations. The
G. C. Doig, T. J. Barber, E. Leonardi, A. J. Neely, H. Kleine   +4 more
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Advanced Flow Control for Supersonic Blowdown Wind Tunnel Using Extended Kalman Filter

Journal of Dynamic Systems, Measurement, and Control, 2013
Supersonic blowdown wind tunnels provide controlled test environments for aerodynamic research on scaled models. During the experiments, the stagnation pressure in the test section is required to remain constant. Due to nonlinearity and distributed characteristics of the controlled system, a robust controller with effective flow control algorithms is ...
Jiaqi Xi, Qiang Zhang, Mian Li, Zhaoguang Wang   +3 more
openaire   +1 more source

Cascade nonlinear feedforward-feedback control of stagnation pressure in a supersonic blowdown wind tunnel

Measurement, 2017
Abstract Current trends in the development of control systems involve disproportionately high costs for embedded software integration and testing techniques that rely almost exclusively on exhaustive testing of more or less complete versions of complex systems. Wind tunnel control systems are not an exception. A formal methodology for supersonic flow
Ilić, Biljana, Miloš, Marko, Isaković, Jovan   +2 more
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Visualization of sidewall vortices in rectangular nozzle supersonic blowdown wind tunnel

Physics of Fluids
This study focuses on the details of the geometry and dynamics of sidewall vortices observed in supersonic wind tunnels with a rectangular cross section of the nozzle and the test section. The formation of sidewall vortices limits the accuracy of the data measured during wind tunnels' testing due to a reduced area of uniform core flow results.
Philip S. Andrews, Philip A. Lax, Flint O Thomas, Sergey B. Leonov   +3 more
openaire   +1 more source