Accession Number : ADP001667

Title :   Contribution to the Modeling of the Ice Accretion Process: Ice Density Variation with the Impacted Surface Angle,


Personal Author(s) : Bain,M. ; Gayet,Jean-Francois

Report Date : JUN 1983

Pagination or Media Count : 8

Abstract : Icing measurements were carried out in natural winter clouds with an instrumented wind tunnel set up at the top of the Puy de Dome (1500 MLS). The microphysical data (liquid water content, droplet spectra) were obtained by using the PMS ASSP 100. The ice density was measured on a rotating cylinder and the ice deposit of the cross section was photographed on a fixed cylinder. We propose to improve this model by taking into account the ice density variation with the angle of impact on the cylinder. The ice density variation with the angle depends on various parameters: pressure, temperature, air speed, liquid water content and especially on the droplet distribution. This improvement is not sufficient to explain some observed profiles; this may be attributed to the fact that the model is not time dependent.

Descriptors :   *Ice formation, *Ice formation indicators, *Cloud cover, *Winter, Cold weather tests, Wind tunnel tests, Density, Water, Drops, Particle size, Water distribution, Atmospherics, Measurement, Thickness, Surface analysis, Angles, Photography, Data acquisition, France, Workshops

Distribution Statement : APPROVED FOR PUBLIC RELEASE