# Formation Mechanism and Motion Characteristics of Multiple Jets in Spherical Section Free Surface Electrospinning

## TL;DR

This study explores how multiple jets form and move in a spherical electrospinning device, helping improve the production of nanofibers.

## Contribution

The study introduces a numerical model combining magnetohydrodynamics and fluid dynamics to analyze jet behavior in spherical electrospinning.

## Key findings

- As the sphere radius increases, jet maximum velocity decreases but jet area and interaction forces increase.
- Jet trajectories expand outward more clearly with larger sphere radii.
- A 75 mm sphere radius was found optimal for efficient jet production and nanofiber manufacturing.

## Abstract

In this study, during the efficient preparation of nanofibers using a spherical section free surface electrospinning (SSFSE) device with different sphere radii, the formation mechanism and motion characteristics of multiple jets were thoroughly investigated through the numerical simulation method. The mechanical model of multiple jets was established, and the key role of electric field intensity in the formation and motion of jets was defined; in addition, the relationship between the jet initial velocity and the electric field intensity distribution on the solution surface was established. On this basis, a magnetohydrodynamic model was introduced, and a turbulence model as well as a volume of fluid model were combined to numerically simulate the jet motion during the SSFSE process. The results showed that as the sphere radius increased, the maximum velocity of the jets gradually decreased. However, the area of multiple jets generated increased, and the interaction force between the jets increased, resulting in a more obvious outward expansion of the jet trajectory. Therefore, the optimal SSFSE device with a sphere radius of 75 mm was determined. Finally, the results of numerical simulation were verified by experiments using a polymeric solution with low conductivity. This study can play a guiding role in effectively increasing the number of jets per unit area of solution surface in actual production, thus achieving continuous, uniform, and efficient preparation of micro-/nanofibers.