@article { ISI:000246532500010,
	title = {Simulation of viscoelastic flows of polymer solutions in abrupt contractions using an arbitrary lagrangian eulerian (ALE) based finite element method},
	journal = {Journal of Non-Newtonian Fluid Mechanics},
	volume = {143},
	number = {2-3},
	year = {2007},
	month = {MAY},
	pages = {157-169},
	publisher = {ELSEVIER SCIENCE BV},
	type = {Article},
	address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS},
	abstract = {<p>We present a method for simulation of viscoelastic flows using an Arbitrary Lagrangian Eulerian (ALE) technique based finite element formulation. The ALE technique provides advantages of both Lagrangian and Eulerian frameworks by allowing the computational mesh to move in an arbitrary manner, independent of the material motion. In the present method, a fractional step ALE technique is employed in which the Lagrangian phase of material motion and convection arising out of mesh motion are decoupled. In the first step the relevant flow and constitutive equations are solved in Lagrangian framework. The simpler representation of polymer constitutive equations in a Lagrangian framework avoids the difficulties associated with convective terms thereby resulting in a robust numerical formulation. In the second step the mesh is moved in ALE mode and the associated convection of the stress is performed using a Godunov type scheme. This ALE technique is easy to implement and can accurately simulate the complex viscoelastic behaviour of transient polymer flow through complex geometries. In the present study, steady flows through abrupt contractions of planar and axisymmetric geometries are studied by performing transient flow simulations until steady state is achieved. The proposed method is validated with previously published numerical and experimental studies for polymer solutions obeying the Oldroyd B and Phan Thien Tanner (PTT) models. The simulated corner and lip vortex enhancement mechanism and flow behavior are in good agreement with experimentally obtained flow visualization photographs. The strength of the proposed method lies in its ability to simulate free surface flows such as swell. (C) 2007 Elsevier B.V. All rights reserved.</p>},
	keywords = {abrupt contraction, Arbitrary Lagrangian Eulerian, finite element, simulations},
	issn = {0377-0257},
	doi = {10.1016/j.jnnfm.2007.02.009},
	author = {Ganvir, Vivek and Lele, Ashish K. and Thaokar, Rochish and Gautham, Basavarsu P.}
}
@article {48453,
	title = {Synthesis of N-oxyethylene substituted imidazolium-based zwitterions as a recyclable solvent for cellulose dissolution},
	journal = {Cellulose},
	volume = {30},
	year = {2023},
	month = {JAN},
	pages = {87-109},
	type = {Article},
	abstract = {<p>
	Cellulose is a readily available, renewable, and natural biomaterial that has the potential to replace synthetic fibres. However, their processing to shaped materials such as fibre or film is still complex and restricted due to its insolubility in most conventional solvents. Herein, we present the synthesis and cellulose dissolution characteristics of a new class of recyclable zwitterions composed of tethered N-oxyethylene substituted imidazolium cation and alkyl carboxylate anion. Investigations on cellulose dissolution showed that increasing the alkyl chain length of carboxylate anion and introduction of oxyethylene unit on imidazolium ring led to better cellulose dissolution ability, and up to 12\% (w/w) cellulose could be dissolved in aqueous zwitterions at 105 degrees C. The thermal behavior of zwitterions and their cellulose solutions was characterized by TGA and found to be more stable than the NMMO and Lyocell solutions. Rheological characterization of cellulose solutions revealed viscoelastic behavior and zero shear viscosity of 6-12\% (w/w) cellulose solution in hexanoate containing aqueous zwitterion was 555 to 5900 Pa.s at 120 degrees C. The characteristics of cellulose solution indicate its potential for processing to cellulose fibre by extrusion through a tiny spinneret. Physico-chemical analysis of regenerated cellulose indicates that zwitterions cause no adverse effect on cellulose structure and morphology during dissolution. The zwitterions are recovered after the cellulose regeneration process, and the recovery was found to be 99.6\% after purification using the ion-exchange method.</p>
},
	keywords = {Carboxylate anion, Cellulose dissolution, Oxyethylene unit, Regenerated cellulose, Rheology, zwitterions},
	issn = {0969-0239},
	doi = {10.1007/s10570-022-04883-1},
	author = {Jadhav, Sachin and Ganvir, Vivek and Singh, Madan Kumar and Shanmuganathan, Kadhiravan}
}
@article {49385,
	title = {Structure and properties of the cellulose fibres spun from imidazolium-based carboxylate functionalized zwitterionic liquid},
	journal = {CARBOHYDRATE POLYMERS},
	volume = {348},
	year = {2025},
	month = {JAN },
	keywords = {cellulose, Direct dissolution, Zwitterionic liquid},
	issn = {0144-8617},
	doi = {10.1016/j.carbpol.2024.122804},
	author = {Jadhav, Sachin and Singh, Dhirendra and Gupta, Deepika and Ganvir, Vivek and Singh, Madan Kumar and Shanmuganathan, Kadhiravan}
}
