arXiv subjects

Tapati Dutta

Publications and source records attributed to Tapati Dutta.

21 records · Page 2Linked to original sources

arXiv2005

Desiccation and Relaxation Regimes in Fracture of Drying Clay Films

A study of crack patterns in laponite films of different thickness is presented. Two cracking regimes are observed. The earlier with a higher rate of desiccation and shrinking has predominantly four-fold vertices in the crack network, while the later regime has less volume shrinking and forms mainly three-fold vertices. The pattern shows a self-similarity under coarse-graining. The graph of area covered by the cracks versus minimum crack-width resolved, scales with the film thickness. Curves representing crack area for different thickness can thus be made to collapse onto a single curve.

cond-mat.soft↗

arXiv2003

Radially Interrupted Viscous Fingers in a Lifting Hele-Shaw Cell

Viscous fingers have been produced in the lifting Hele-Shaw cell, with concentric circular grooves etched onto the lower plate. The invading fluid (air) enters the defending newtonian fluid - olive oil as fingers proceeding radially inwards towards the centre. The fingers are interrupted at the circular groove, and reform as secondary fingers. The effect of the grooves is to speed up the fingering process considerably and the fingers now reach the centre much faster. We explain this by comparing the variation in velocity of the fingers in the normal HS cell and the grooved cells with time. In the normal HS cell the fingers move fastest on initial formation and slow down later. Since in case of the grooved plate, the fingers reform and receive a boost in their speed each time they encounter a groove, the fingers proceed to the centre faster. PACS nos. 47.20.Gv, 47.54.+r, 68.03.-g

cond-mat.soft↗

arXiv2002

Condensation and evaporation on a randomly occupied square lattice

We study the evolution of an initially random distribution of particles on a square lattice, under certain rules for `growing' and `culling' of particles. In one version we allow the particles to move laterally along the surface (mobile layer) and in the other version this motion is not allowed (immobile case). In the former case both analytical and computer simulation results are presented, while in the latter only simulation is possible. We introduce growth and culling probabilities appropriate for condensation and evaporation on a two-dimensional surface, and compare results with existing models for this problem. Our results show very interesting behaviour, under certain conditions quite different from earlier models. We find a possibility of hysteresis not reported earlier for such models. ~

cond-mat.soft↗