Abstract
An isolated dynamic microburst is modelled in the laboratory by releasing an elevated volume of salt water solution which is slightly heavier than ambient fresh water, allowing it to fall onto a horizontal plate and develop into a turbulent microburst vortex ring. This experimental model exhibits many of the features of naturally occurring microbursts which are known to be a hazard to aviation. Flow visualization methods are used to observe the event and a high resolution video camera is used to record it. In the current investigation hot film velocity measurements are made at a number of radial positions near the ground. Realistic estimates of the wind field in real microbursts may be obtained from these measurements by means of a previously developed scaling law. Flow visualization and velocity measurements support a description of the microburst structure in its transition from a vortex dominated flow to a radial gravity current in its late stages.
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This work was supported by NASA-Ames Research Center, through a NASA-Ames University Consortium Agreement, contracts NCA2-329 and NCA2-622. We also acknowledge a grant from the University of Minnesota Graduate School.
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Yao, J., Lundgren, T.S. Experimental investigation of microbursts. Experiments in Fluids 21, 17–25 (1996). https://doi.org/10.1007/BF00204631
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DOI: https://doi.org/10.1007/BF00204631