The transport of nutrients in porous media can be considered as a mesoscopic mechanics problem. Micromechanics can thus be applied to investigate the behaviour of such a multiphase system. On meso length scale (microns), effective numerical simulation methods include Dissipative Particle Dynamics (DPD), Smoothed Dissipative Particle Dynamics and Lattice Boltzmann methods. in DPD, the method to be considered here, DPD particles are regarded as groups of molecules and thus the DPD simulations can be conducted on time and length scales that are far beyond those of molecular simulations. We propose using freely-movable DPD particles to model the fluid (water) and spring-connected DPD particles to represent the nutrients and soil grains. Through the interactions of three types of particles, the movement of nutrients in porous media can be tracked in a direct manner. Furthermore, force fields (e.g. magnetic) can be easily accommodated in the DPD system by applying appropriate potentials. This direct (natural) simulation approach is expected to lead to a significant improvement in accuracy over continuous-medium-based approaches.

Professor Nam Mai-Duy

• Computational Engineering and Science Research Centre
• Institute for Agriculture and the Environment
• School of Engineering

• Interdisciplinary Engineering
• Numerical and Computational Mathematics
• Soil Sciences

• Doctor of Philosophy (DPHD)