Accession Number : ADP005536

Title :   The Flow Around a Squared Obstacle,

Corporate Author : INSTITUTO SUPERIOR TECNICO LISBON (PORTUGAL)

Personal Author(s) : Durao,D. F. ; Heitor,M. V. ; Pereira,J. C.

Report Date : NOV 1986

Pagination or Media Count : 9

Abstract : Laser-Doppler measurements of the velocity distribution around and in the wake of a two-dimensional squared obstacle for Re = 14000 are reported. The results were measured with a counter interfaced with a microprocessor. The counter was built based on a specific design to quantify and diminish errors resulting from bias sources. In addition, the periodic character of the flow in the wake was characterised by measurements of turbulence spectra with FFT instrumentation. The values of the predominant frequencies were correlated with the flow Reynolds number.

Descriptors :   *LASER VELOCIMETERS, FLUID FLOW, RECIRCULATION, REYNOLDS NUMBER, VORTEX SHEDDING, RIGHT ANGLES, BLUNT BODIES, TWO DIMENSIONAL, COUNTERS, MICROPROCESSORS, DOPPLER SYSTEMS, LASER BEAMS, FORWARD SCATTERING, WAKE, PERIODIC VARIATIONS, VELOCITY, TURBULENCE, POWER SPECTRA, STATISTICAL DATA, PRECISION, BIAS, FAST FOURIER TRANSFORMS, PORTUGAL

Subject Categories : Fluid Mechanics
      Test Facilities, Equipment and Methods

Distribution Statement : APPROVED FOR PUBLIC RELEASE