ENTRAINMENT STUDIES IN CLOUD-LIKE FLOWS USING NOVEL SCANNING TOMOGRAPHY TECHNIQUE

etc15 Tracking Number 272

Clouds are one of the major sources of uncertainty in climate prediction .The present work is to study the dynamics of orographic clouds. We considered a planar turbulent wall jet with off source volumetric heating as an appropriate low order fluid-dynamical model for studying the turbulence and entrainment in orographic-clouds. Entrainment was found to reduce drastically with the off-source volumetric heat addition. We found that the reduction of entrainment started at a bulk-Richardson number which was an order of magnitude smaller than that seen in earlier experiments [1] on free standing cumulus clouds. This is consistent with observations in real orographic clouds which develop as a thin sheet rising along the mountain slope. We have developed a novel scanning tomography technique for getting concentration field in turbulent shear flows. This technique is being applied on cloud-like flow to understand the entrainment characteristics. Detailed results will be presented at the conference.