A Computational Model of Nanoparticle Growth

A Computational Model of Nanoparticle Growth: from Spark Ablation

van der Maesen, Bibianne (TU Delft Electrical Engineering, Mathematics and Computer Science; TU Delft Delft Institute of Applied Mathematics)

van Gijzen, M.B. (mentor)
Boeije, M.F.J. (mentor)
Heemink, A.W. (mentor)

Delft University of Technology

Applied Mathematics | Computational Science and Engineering

2018-11-16

Though the commercialisation of nanotechnology began only 30 years ago, it has developed into one of the fastest growing industries in terms of research and design, with an unlimited amount of possibilities that will transform industries from how we know them today. The advancement of nanotechnology relies on the actual production, control and integration of nanoparticles. VSPARTICLE is a nano start-up which developed the VSP-G1, a generator that produces nanoparticle aerosols using a gas-phase process called spark ablation.

The aim of this thesis is to develop and validate a computational model of the nanoparticle production process in the VSP-G1. Such a model will simulate the effect of certain physical mechanisms on the composition of the produced aerosol and track the corresponding particle size distribution (PSD) throughout the production process.

Brownian coagulation and diffusion are identified as main aerosol mechanisms and form the mathematical basis of the model. Approximation formulas provide the initial conditions which directly depend on the VSP-G1 input parameters. The Log-Normal Method of Moments (Log-MoM) is used to approximate the model by deriving the geometric mean, standard deviation and total particle concentration of the PSD. Last, the solution is computationally approached using the Forward Euler numerical method.

A theoretical and experimental validation proved a sufficient accuracy of the model with respect to nanoparticle growth in the VSP-G1. In particular, the predictions of the mean particle size maintained nanometer accuracy in compliance with experiments. To assist future research, accuracy ranges are presented that provide compliance criteria between the modelled results and the actual output of the VSP-G1. Finally, an improved function for the particle size evolution due to pure, monodisperse coagulation is derived based on the experimental validation process.

The computational model will provide researchers with an analysis regarding the sensitivity of the VSP-G1 input parameters. Furthermore, the models framework, consisting of mathematical and physical processes, will provide a better scientific understanding of the system. Finally, the model can contribute to the production of pure, tailor-made nanoparticles by performing as an operational guide for the VSP-G1.

nanotechnology
mathematical modelling
Smoluchowski

http://resolver.tudelft.nl/uuid:ec572aed-12af-4925-bcb5-562ff7d8aa09

2023-11-16

Student theses

master thesis

© 2018 Bibianne van der Maesen