Nonlinear viscous liquid jets from a rotating orifice

Abstract

Abstract. A liquid jet follows a curved trajectory when the orifice from which the jet emerges is rotating. Surface tension driven instabilities cause the jet to lose coherence and break to form droplets. The sizes of the drops formed from such jets are in general not uniform, ranging from drops with diameters of the order of the jet diameter to droplets with diameters which are several orders of magnitude smaller. This presentation details a theoretical investigation of the effects of changing operating parameters on the break-up of curved liquid jets in stagnant air at room temperature and pressure. The Navier-Stokes equations are solved in this system with the usual viscous free surface boundary conditions, using an asymptotic method based upon a slender jet assumption, which is clearly appropriate from experimental observations of the jet. We also present nonlinear temporal simulations of the breakup of the liquid jets using our slender theory. These simulations based upon both a steady trajectory assumption, and the more general equations which allow for an unsteady trajectory, show all the breakup modes viewed in experiments. Satellite droplet formation is also considered.

Numerical and experimental study on the steady cone-jet mode of electro-centrifugal spinning

“…The basis used for solving the equations governing the electrified jet through air-sealed electro-centrifugal spinning is the perturbation theory proposed by Pȃrȃu et al, 22 who used this methodology to simulate the behavior of a bent jet The applied coordinate system is an extension of the cylindrical polar coordinates, (s, n, ϕ), where s is the arclength along the jet axis and (n, ϕ) is the polar coordi-nate in any cross section of the jet. The centerline was described by a Cartesian coordinate system (X(s, t), 0, Z(s, t)).…”

“…Readers are referred to 22 for further details regarding the derivation of where γ is the surface tension, κ is the surface curvature, and I…”

“…18 Wallwork et al, 19 Decent et al, 20 Wong et al, 21 and Pȃrȃu et al 22 experimentally and numerically investigated the prilling process for the production of fertilizers, considering a air-sealed centrifuge spinning, 1 and air-sealed electrocentrifugal spinning 12 all have proven successful as viable rotational jet. Dabirian et al [23][24][25] have experimentally investigated methods to mass-produce polymeric nanofibers, allowing a significant increase in yield and simplifying the production.…”

Numerical and experimental investigation on static electric charge model at stable cone-jet region

“…The basis used for solving the governing equations for an electrified jet is the perturbation theory prop osed by Pȃ rȃ u et al, 28 who used this methodology to simulate the behavior to an incompressible Newtonian fluid, as where u is the velocity, ρ is the density, p is the pressure,…”

Rotary jet spinning review – a potential high yield future for polymer nanofibers

“…Modeling the RJS process involves the use of basic parameters such as polymer viscosity, centrifugal force, Coriolis force, air drag on the fiber and also the evaporation time of a solvent in the collector during spinning. 53 Several publications investigating viscoelastic properties and production methods 163,[186][187][188][189][190][191] provide great insight into the complexity of the RJS process, and will provide useful directions for future RJS models.…”