We study the effects of rotation on the growth and saturation of the double-diffusive fingering (thermohaline) instability at low Prandtl number. Using direct numerical simulations, we estimate the compositional transport rates as a function of the relevant non-dimensional parameters -the Rossby number, inversely proportional to the rotation rate, and the density ratio which measures the relative thermal and compositional stratifications. Within our explored range of parameters, we generally find rotation to have little effect on vertical transport. However, we also present one exceptional case where a cyclonic large scale vortex (LSV) is observed at low density ratio and fairly low Rossby number. The LSV leads to significant enhancement in the fingering transport rates by concentrating compositionally dense downflows at its core. We argue that the formation of such LSVs could be relevant to solving the missing mixing problem in RGB stars.

The present study highlights the changes in morphology in a Sn matrix during pulsed electrodeposition of a Sn−Cu near-eutectic alloy with varying current density in an acidic electrolyte. 3D image construction has been employed using SHAPE V7.3; Shape Software: Kingsport, Tennessee, USA to replicate the shape of grown crystals and analyze the results. It is observed that the growth morphology changes with the introduction of high index planes at higher current densities. Furthermore, a growth pattern occurs with high index planes formed from a stepped structure in low index planes. There has been a change in growth direction from ⟨001⟩ to ⟨110⟩ at higher current densities. At very high current densities, sympathetic or secondary nucleation is observed.

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Copper has been electrodeposited on copper (FCC) and mild steel (BCC) substrates from acidic sulphate bath with and without cetyl trimethyl ammonium bromide at 0.25, 2, 6 and 9 V. It is found that the surface morphology varies with the change in overpotential, but not with the change in substrate. On the contrary, the crystal shape is found to be independent of the applied overpotential, but varies with the bath chemistry or choice of substrate.