Compaction dynamics of wet granular materials under thermal cycling

Dr. Maryam Pakpour (IPM)
Monday, 95/01/30 (April 18, 2016), 15:30
Auditorium

Abstract
We study the effect of liquid volume fraction on the packing dynamics of wet granular materials under thermal cycling. Dilation of water between the particles due to the thermal nature of the driving force can change the configuration of the pile during the freezing and melting. Our results show that beyond the remarkable attraction capillary force, independently of the initial packing fraction, the granulate tend to converge to the random loose packing configuration which obeys an inverse exponential law related to the liquid volume fraction. The onset and the average rate of decompaction show an exponential dependence on the liquid volume fraction. We have shown that the packing dynamics can be well modeled within a model of an overdamped particle in a tilted potential. It means the granular pile under Laplace pressure is affected by a deep potential which prevents the rearrangement of the grains. In this case the liquid volume fraction controls the required energy to escape the barrier to lead the system to the stable state.

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دکتر مریم پاکپور (پژوهشگاه دانشهای بنیادی)