Modelling of Heavy Gas Plumes in a Water Channel
An experimental study has been made of the turbulent mixing of a negatively buoyant salt solution injected into a neutral unobstructed turbulent boundary layer in a water channel flow. Particular emphasis is placed on plumes developed from low momentum sources fitted flush to the surface.
Flow visualisation and conductivity probes, to measure the mean concentration have allowed plume boundaries to he determined for a wide range of flow velocities, source flow rates, density ratios, source sizes and differing surface roughnesses. Ground level concentration profiles indicate a two stage decay which becomes more pronounced as the relative heaviness of the plume is increased.
A comparison of plume boundary data and mean concentration data with available wind and water tunnel data show reasonable agreement and indicate that water channel modelling of heavy gas spills may be an attractive alternative to wind tunnel modelling.
KeywordsWind Tunnel Water Channel Richardson Number Roughness Element Stage Decay
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