Video images of smoke dispersion in the near wake of a model building. Part 1. Temporal and spatial scales of vortex shedding

Technical Report · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5674684

Huber, A H

In a wind-tunnel study, recorded video images of smoke dispersion in the wake of a rectangular-shaped building were analyzed. A continuous source of smoke was emitted at floor level, midway along the leeward side of the building. Smoke was observed to build up within a region adjacent to the building. Then the smoke was periodically swept away by vortices shed from the leeward building sides and roof. The applicability of analyzing time series of smoke scattered light for selected quantized video picture elements was favorably demonstrated. Temporal and spatial scales of vortex-shedding of smoke puffs near the center of the wake were quantified through the calculation of spectral densities and autocorrelations. The dominant frequencies (cycles/second) near the center of the wake flow were found to be 0.1-0.3 times the ratio of the velocity to the building height. Estimated integral length scales near the center of the wake flow were found to be 1-2 times the building height.

• Research Organization: Environmental Protection Agency, Research Triangle Park, NC (USA). Atmospheric Research and Exposure Assessment Lab.
• OSTI ID: 5674684
• Report Number(s): PB-89-206676/XAB; EPA--600/J-88/332
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400 -- Engineering-- Heat Transfer & Fluid Flow
500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AEROSOLS
AIR POLLUTION
ATMOSPHERIC CIRCULATION
BUILDINGS
COLLOIDS
DATA
DISPERSIONS
EXPERIMENTAL DATA
FLOW VISUALIZATION
FLUID FLOW
INFORMATION
NUMERICAL DATA
POLLUTION
RESIDUES
SMOKES
SOLS
TUNNELS
TURBULENCE
UNDERGROUND FACILITIES
VORTEX FLOW
VORTICES
WIND
WIND TUNNELS