Date of Award
1-1-2017
Document Type
Dissertation
Degree Name
Ph.D.
Organizational Unit
Daniel Felix Ritchie School of Engineering and Computer Science, Mechanical and Materials Engineering
First Advisor
Yun-Bo Yi, Ph.D.
Second Advisor
Martin Margittai
Third Advisor
Jun Zhang
Fourth Advisor
Ali Azadani
Keywords
Computational simulation, Diffusion, Finite element analysis, Heterogeneous materials, Monte Carlo Method, Random walk
Abstract
Heterogeneous materials provide a unique combination of desirable mechanical, thermal or electrical properties. This dissertation presents several micro-structure modeling approaches to predict the effective properties of heterogeneous materials and demonstrates its certain application toward two highly heterogeneous, unconventional structural composite materials (carbon fiber reinforced composite materials and graphene nanoplatelets composite). By using the efficient computational algorithm based on the FEA, a randomly oriented disk-shaped particles system are generated. A new element partition scheme based on the vector operations and geometry of inclusion has been implemented to mesh the intersected disks. The computed equivalent conductivity is expressed as a power-law function form with the key parameters determined from curve fitting. Also, we proposed a novel random walk method to study the 2-D circular or elliptical and 3-D spherical or ellipsoidal non-overlapping system diffusion process. A Monte-Carlo scheme is applied to generate the particulate system for simulation. The effective diffusion coefficient has been predicted and compared to the finite element method and effective medium theory. The aspect ratio effect also investigated and compared to other numerical studies.
Publication Statement
Copyright is held by the author. User is responsible for all copyright compliance.
Rights Holder
Jian Qiu
Provenance
Received from ProQuest
File Format
application/pdf
Language
en
File Size
130 p.
Recommended Citation
Qiu, Jian, "Computational Modeling of Percolation Conduction and Diffusion of Heterogeneous Materials" (2017). Electronic Theses and Dissertations. 1375.
https://digitalcommons.du.edu/etd/1375
Copyright date
2017
Discipline
Materials Science