Simulation and experimental study of multi nozzle arrangements on electrospun jets and their resultant nanofibrous properties / Hanna Sofia Saleh Hudin

• Main Author: Hanna Sofia , Saleh Hudin
• Format: Thesis
• Published: 2024
• Subjects: TJ Mechanical engineering and machinery
• Online Access: http://studentsrepo.um.edu.my/15469/1/Hanna_Sofia.pdf; http://studentsrepo.um.edu.my/15469/2/Hanna_Sofia.pdf; http://studentsrepo.um.edu.my/15469/

Electrospinning is a simple and versatile method to fabricate nanofibers with the application of high voltage. Owing to their distinctive properties, electrospun nanofibers could be useful in a variety of applications, including biomedical, filtration, protective textiles, sensors, and energy storage devices. Even though the setup is quite simple and straightforward, the process is complex and time-consuming, with low product yields. Multi-nozzle electrospinning is a direct approach to increasing nanofibre productivity. However, the addition of nozzles usually causes processing issues and deterioration of fibre quality due to electric field interference and low process homogeneity, restricting the prospect of mass production. This study aims to investigate the effects of multi-nozzle configurations and parameters on the electrospinning of poly(ethylene oxide) fibres. Simulations of the electric field were carried out using finite element analysis, and the jet paths were modelled using the discrete element method. The properties of jets and fibres measured from the experiments were analysed and compared between different setups. Different linear nozzle arrangements of equal and unequal spacings were tested, and the results indicate that the electric fields in the electrospinning process can be altered by varying the number of nozzles and spacing between nozzles. The change in electric field intensity and distribution consequently affects the processibility, jet behaviour, and resulting nanofibres. In multi-nozzle electrospinning, the process is notably improved by employing unequal nozzle arrangements with larger inner-to-outer nozzle distance ratios, resulting in increased electric field strength and uniformity, lower voltage requirement, and increased uniformity of the deposited mats and fibres. In terms of productivity, such arrangements also tend to maximise fibre output from a continuous and uninterrupted process, which can be beneficial in the efforts of mass production of nanomaterials. For the setup with four and five nozzles, the unequal nozzle distribution with a 3:1 inner-to-outer nozzle ratio was found to be the optimal design for improved performance. The prediction model developed was also found to reasonably predict the deflection of jets in the multi-nozzle electrospinning process.