Sachin Kumar Jain

Indian Institute of Technology Madras | IIT Madras · Department of Mechanical Engineering

Remarkably, we experimentally evidenced normal field instability-driven reversible transition from ferrofluid droplet to spikes, when a sessile ferrofluid drop is exposed to a varying magnetic field gradient due to an approaching magnet, without flipping its direction of motion. We find the reversible transition is attributed to the critical magnet...

We report encapsulation of microparticles in aqueous ferrofluid droplets in a primary continuous phase (CP) and sorting of PED from empty droplets (ED) at the interface of CP in co-flow with a second continuous phase using a magnetic field. We find the encapsulation process results in a size contrast between the PED and ED that depends on the flow...

Encapsulation of particles inside droplets is a stochastic process that follows a Poisson distribution [1]. We report encapsulation of microparticles in aqueous ferrofluid droplets in a primary continuous phase (CP) and sorting of particle encapsulated droplets (PED) from empty droplets (ED) at the interface of continuous phase (CP) in coflow with...

Handling and manipulation of particle-encapsulating droplets (PED) have profound applications in biochemical assays. Herein we report encapsulation of microparticles in aqueous ferrofluid droplets in a primary continuous phase (CP) and sorting of PED from empty droplets (ED) at the interface of the CP in coflow with a second continuous phase using...

We show that adjacent liquid droplets exhibit long-range attraction and repulsion on an immiscible liquid impregnating a surface when either the drop or the impregnating liquid is volatile. Remarkably, we find that at small times the interaction is attractive, analogous to the "Cheerios effect", but at large times the interaction becomes repulsive...

Manipulation of aqueous droplets has profound significance in biochemical assays. Magnetic field-driven droplet manipulation, offering unique advantages, is consequently gaining attention. However, the phenomenon relating to diamagnetic droplets is not well understood. Here, we report understanding of trapping and coalescence of flowing diamagnetic...

We report on-demand relocation of aqueous droplets flowing inside an oil-based ferrofluid and coalescence with an aqueous stream in the presence of a non-uniform magnetic field. We found that the ratio of two timescales magnetic and advective, governs the relocation. It is found that, higher is the ratio, lesser is the deflection experienced by the...

Manipulation of aqueous droplets in microchannels has great significance in various emerging applications such as biological and chemical assays. Magnetic-field based droplet manipulation that offers unique advantages is consequently gaining attention. However, the physics of magnetic field-driven cross-stream migration and the coalescence of aqueo...

The efficiency of heat transfer in processes likAe bcsotmrabcuts tion and spray cooling is highly dependent on the surface area exposed to the surrounding medium. The shapes (characterized by sphericity), sizes (equivalent diameter), as well as the number of droplets formed, are some of the most important parameters defining the overall behaviour o...