Self-folding using capillary forces

Self-folding broadly refers to the assembly of 3D structures by bending, curving, and folding without the need for manual or mechanized intervention. Self-folding is scientifically interesting because examples of self-folded structures, from plant leaves to gut villi to cerebral gyri, abound in nature. From an engineering and technological...

Microscale surface tension and its applications

A review on suppression and utilization of the coffee-ring effect

Evaporation of sessile droplets containing non-volatile solutes dispersed in a volatile solvent leaves behind ring-like solid stains. As the volatile species evaporates, pinning of the contact line gives rise to capillary flows that transport non-volatile solutes to the contact line. This phenomenon, called the coffee-ring effect, compromises...

Investigation of foam generation, propagation and rheology in fractures

Naturally fractured reservoirs (NFRs) are found in many countries around the globe, in almost every lithology. These reservoirs can be carbonates, sandstones, or shale, in the case of unconventional or basement reservoirs. NFRs have been explored and exploited globally for groundwater, geothermal energy, hydrocarbon production, coalbedmethane...

Modeling of low-capillary number segmented flows in microchannels using OpenFOAM

Modeling of low-Capillary number segmented flows in microchannels is important for the design of microfluidic devices. We present numerical validations of microfluidic flow simulations using the volume-of-fluid (VOF) method as implemented in OpenFOAM. Two benchmark cases were investigated to ensure the reliability of OpenFOAM in modeling complex...

Asphalt mastic self healing (abstract)

Stability regime of pulse frequency for single event electrospraying

This study demonstrates that the hydrodynamic phenomena taking place inside the capillary limits the frequency range of voltage pulses for stable single event electrospraying (SEE), when the meniscus/cone size is defined by the inner diameter of the nozzle. For the analysis of SEE, we used a one-dimensional model describing the displacement and...