We study how interfacial forces impact the dynamics of complex fluids such as suspensions, emulsions, foams, micro-emulsions, polymers and glasses. These are already crucial for industrial processes and products due to their peculiar rheology and flow characteristics. But we are now in an era where industries must maneuver through quick transitions in technologies under restricting resources, laying stress on novel materials that tailor to a purpose with a specific property. Through a combination of experiments and theoretical models we create the desired characteristics by using fundamentals of solid mechanics, hydrodynamics, surface phenomena and statistical thermodynamics. We rely on experimental techniques of imaging, diffraction and scattering, rheometry and use computational techniques such as molecular dynamics and finite element methods.
Research Areas
Certain crude oils pose severe challenges for flow assurance due to the high concentration of waxes. Being high molecular weight compounds, waxes crystallize out of the oil as largely aspherical particles and readily form a network which occludes a large volume of oil and prevents free flow of crude through pipelines. By using polymeric molecules comprising of long carbon chains, we hinder the process of wax network formation in crude oil systems.
Crude oil is a complex mixture of many components, in which paraffin waxes, asphaltenes, and resins are predominantly responsible for the problem of flow assurance. The waxes which are non-polar compounds, crystallize when the ambient temperature falls below pour point of crude oil, to form a solid-like suspension. On the other hand, asphaltenes and resins are relatively high molecular weight polar compounds. These polar particles act as the nuclei for the crystallization of waxes and they from a strong network, which can impede its…
The hydrodynamic behavior of fractal aggregates plays an important role in various applications in industry and environment, and has been a topic of interest over the past several decades. Despite this, crucial aspects such as the relationship of the mobility radius, Rm, with respect to the fractal dimension, df, the fluid penetration depth ,d, have largely remained unexplored. Herein, we examine these aspects across a wide range of df, by employing a Stokesian Dynamics Approach. It takes into account all orders of monomer-monomer interactions to construct the resistance matrix for the…
Quite often complex fluids exhibit solid-like behavior due to the formation of networks by the suspended particles. A jammed state is achieved wherein the motion of the suspended particles tends to cease. Such solid-like behavior can also be achieved at very low concentrations for aspherical particles, where the networks are formed due to excluded volume and short-range attractions. However, such particulate networks tend to exhibit brittleness on the slightest of the disturbance, thus irreversibly transitioning to liquids at the same conditions of concentration, ambient…
