Orientation measurement of graphically simulated nanoscale electrospun fibrous structures using particle-based modeling and 2-D metaball fitting

Abstract

Purpose

The purpose of this paper is to provide an efficient tool for simulating electrospinning process in virtual 3D space and optimizing experimental parameters. The fiber orientation from virtual or real electrospinning process can be easily measured using the image analysis technique. Using the semi-implicit Euler integration, the time integration can be more fast and stable, which enabled optimization of the electrospinning process. Also boundary conditions can be easily adopted during conjugate gradient matrix solving step.

Design/methodology/approach

To simulate the electrospinning process, the authors have adopted a particle-based modeling technique using the molecular dynamics theory, which is known to be suitable for modeling materials with nonlinear and nonhomogeneous behavior such as fibers or fabrics. Gravitational, tensional, and electrostatical forces and their Jacobians were carefully defined and chosen to maintain the stability of the governing equation. Preconditioned conjugate gradient method was used to solve the matrix iteratively with boundary conditions. The 2-D metaball fitting technique, which was applied in the previous research (Sul et al., 2009) on experimental nanofiber scanning electron microscopy images, was utilized with virtual nanofiber images. A staircase function and a new shading language were proposed to automatically calculate the orientation and radius distribution of the graphically simulated electrospun fiber structures. The automatic measurement procedure was verified via graphically designed virtual replica images. Also the orientation tendency acquired from the simulation was compared with that of experimental data.

Findings

Simulation result of fiber orientation showed linear relationship with the collecting drum speed. Use of particle-based method generated a simple system to simulate electrospinning process.

Originality/value

The semi-implicit Euler integration was applied to the electrospinning process and the final linear system was numerically stable to solve.

Citation

Moon, S.H., Hong, K.H., Lee, J. and Sul, I.H. (2018), "Orientation measurement of graphically simulated nanoscale electrospun fibrous structures using particle-based modeling and 2-D metaball fitting", International Journal of Clothing Science and Technology, Vol. 30 No. 1, pp. 122-136. https://doi.org/10.1108/IJCST-04-2017-0040