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Rotor induced air movements and their effects on droplet dispersal

Published online by Cambridge University Press:  04 July 2016

C. S. Parkin
C. S. Parkin*
Affiliation:
CIBA-GEIGY Agricultural Aviation Research Unit, Cranfield
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Extract

The dispersal of droplets sprayed from an aircraft, be it fixed or rotary winged, is affected by influences which can be placed in four categories:

  • 1. Particle characteristics e.g. terminal velocity.

  • 2. Aircraft wake.

  • 3. Meteorology.

  • 4. Nozzle or atomiser position.

Although all four categories combine to produce a particular application the relative importance of each influence varies with particular circumstances. Large particles for instance, are little influenced by air movement and so aircraft wake and meteorology are unimportant. Small droplets, on the other hand, have low terminal velocities and are more easily affected by air movements. Situations where wake predominates over meteorology are usually those where flying heights and wind speeds are low. For example, in Ultra Low Volume spraying, Lawson and Uk (1979) found wake effects at low flying heights.

Type
Research Article
Information
The Aeronautical Journal , Volume 83 , Issue 821 , May 1979 , pp. 183 - 187
Copyright
Copyright © Royal Aeronautical Society 1979 

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Footnotes

*

c/o Cranfield Institute of Technology, Cranfield, Bedford MK43 0AL.

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