Finally, the effects of various fluid properties on the dimensions of these links are assessed, illustrating the viscous dissipation at the time of collisions.įurthermore, the air entrainment due to impingement of a water jet on a pool is studied extensively to understand the physics of the initiation and the cluster of bubbles formed below the free surface. Further, the formation of higher order links is proposed as equivalent to the collision between the liquid rims bounding the sheet, modeled as the jets of reduced strengths and smaller impingement angles.

The analogy helps to take into account the role of surface tension and other forces on the shape and size of the liquid sheets. Citing analogy between the impact of jets for the formation of elemental links and traversal of non-deformable fluid quanta after the collision, an attempt has been made to understand the fundamental physics of this phenomenon through force balance. For the understanding of chain profiles over a wide range of operating parameters, a correlation has been proposed based on numerical simulations and subsequent regression analysis. This has been generalized over the entire chain structure. The influence of several non-dimensional parameters has been found on the shape of the first link of the chain. Further, a scaling law is presented for the variation of fluid velocity across the azimuthal direction of the flow. Their radial dispatch after the collision of jets is followed by self-similar paths with respect to the chain outer periphery. To understand the behavior of fluid parcels inside the chain, flow is studied with streamlines. Since the velocity of the sheet is super-critical (higher than the speed of the capillary waves), the first link is studied for the flow kinematics. This structure is analyzed to pertain towards a steady state. The sheet subsequently transforms into a chain like fluidic structure with successive dwarf links in mutually orthogonal planes. The collision between liquid jets leads to the formation of a sheet in the median plane and is illustrated numerically. Interactions between two facing liquid jets and consequences of jet impingement onto a pool are studied using detailed numerical simulations and intelligent experimental investigations. The multi-scale model developed can be easily extended to investigate other phenomena of fluid dynamics. Moreover, an inertia driven atomization due to the collision of liquid jets is also discussed. For the single liquid jet case, sinusoidal instability is clearly observed in the cylindrical jet along with the formation of an umbrella-like structure at the tip. Detailed simulations are carried out for the phenomenological study of two cases of atomization, namely, shear induced atomization due to high gas flow around the circular jet and modulated velocity instability induced atomization. As a case study, atomization of a liquid jet is studied numerically. Present report discusses the two-way coupled Eulerian-Lagrangian model of multi-scale simulations. More often than not, these involve multiple scales from the size of droplets in millimeters to lengths of liquid jets in meters. Numerical simulation of these phenomena can help us to not just understand the fundamental Physics involved but also to design accurate equipment. Two phase flows are ubiquitous in nature and industries, from atomization of shower jets to the entrainment process in huge industrial mixtures.

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