Convegni ATI - Accesso riservato soci CTI

Autore: Cossali GE, Marengo M, Santini M, Watanabe J

Collana: CA - 57 - Pisa 2002

Note:
This work is an experimental analysis of impact of single drops on a solid heated surface at different temperatures, so as to consider different exchange regime from nuclear boiling to Leidenfrost. Digital high resolution images are used to both view and measure at different times the drop deformation in order to characterize the spatial distribution and morphology of secondary droplets. By the complementary technique of Phase Doppler Anemometry (PDA) is possible to characterize the secondary atomization where the droplets are too small to be measured with the image technique. PDA measure offers also the possibility to define secondary droplets velocity in different splash regimes. The first results of our investigation are summerised with graphics showing the correlations between time versus velocity and diameter of secondary atomization in different boiling regimes, with some images about morphology of the impact and particularly explosion from film into the bubble boiling regime.