Results from asymptotic analysis approach. The “simulated profile” lines are the radius predictions given using different fits of the initial radius profile development. It is seen that the initial radius fits (which are supplied arbitrarily) greatly influence the results obtained. For this reason, this approach is not used in the subsequent analysis.
Jet profiles of PEO jets. Left to right: PEO WSR-301, initial jet development; PEO WSR-301 jet 10–12 cm from spinneret; PEO-2M initial jet; PEO-2M jet 10–12 cm from spinneret, showing the appearance of axisymmetric instability.
Extracted experimental radius profiles for PEO WSR-301 (top) and PEO-2M (bottom) and accompanying trendline fits (spinning conditions as in Table IV).
Stable jet axial stress and radial stress and profiles for PEO WSR-301 and PEO-2M.
Stable jet surface charge density profiles for PEO-2M and PEO WSR-301. Note that the charge densities obtained for are unphysical because the underlying assumption that (far from the spinneret) breaks down.
Stability analysis results: top: PEO WSR-301; bottom: PEO-2M. The growth rate and wave number obtained from the high speed images during electrospinning are shown for comparison.
Stability analysis results for various values along the jets.
Energy analysis results for low conductivity PIB Boger fluid (Ref. 2). It is seen that the instability is driven solely by surface tension (the net growth of the instability is represented by ). The viscous, non-Newtonian viscous and electric field terms are stabilizing.
Energy analysis results for PEO WSR-301 fluid. In contrast to the PIB Boger fluid case, the term driving the axisymmetric instability is principally the electric field (charge interaction) term.
Energy analysis results for PEO-2M fluid.
Comparison of various modes for PEO WSR-301 and PEO-2M.
Influence of the Deborah number on the instability growth rate.
Influence of polymeric viscosity on the instability growth rate.
Characteristic scales and dimensionless groups used in the nondimensionalization of the jet governing equations. Further details can be found elsewhere (Ref. 2).
Explanation of nomenclature used in Eq. (7).
Physical properties of PEO/water fluids.
Dimensionless group values.
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