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A Wind Tunnel Study of the Effects of Turbulence on the Growth of Cloud Drops by Collision and Coalescence

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  • 1 Institute for Physics of the Atmosphere, Johannes Gutenberg University, Mainz, Germany
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Abstract

A set of wind tunnel experiments was carried out to investigate the growth of single drops by collision coalescence with small droplets in laminar and turbulent flow. Analysis of the experiments shows that under otherwise similar conditions, there exists a tendency toward a faster drop growth under turbulence. The observed growth under laminar conditions agrees well with computed continuous growth of a collector drop using collision efficiencies reported in the literature.

Corresponding author address: Otmar Vohl, Institute for Physics of the Atmosphere, Becherweg 21, Johannes Gutenberg University Mainz, 55128 Mainz, Germany.

Email: vohl@mail.uni-mainz.de

Abstract

A set of wind tunnel experiments was carried out to investigate the growth of single drops by collision coalescence with small droplets in laminar and turbulent flow. Analysis of the experiments shows that under otherwise similar conditions, there exists a tendency toward a faster drop growth under turbulence. The observed growth under laminar conditions agrees well with computed continuous growth of a collector drop using collision efficiencies reported in the literature.

Corresponding author address: Otmar Vohl, Institute for Physics of the Atmosphere, Becherweg 21, Johannes Gutenberg University Mainz, 55128 Mainz, Germany.

Email: vohl@mail.uni-mainz.de

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