A novel multiple-phase, multiple-component, thermal lattice Boltzmann model

The lattice Boltzmann method (LBM) is gaining traction as a powerful approach to fluid flow simulation. In this work, developments toward the incorporation of more complex physical phenomena into the LBM are presented. As will be discussed, existing approaches are currently inadequate for thermal ows with wall interactions and multiple components. A novel methodology will be detailed, which enables the simulation of multiphase, multicomponent, thermal ows. The need for these simulation techniques is clear. As energy densities in electronic devices rapidly increase, improved two-phase microchannel heat exchanger designs are of great interest. Similarly, with the implementation of phase separation as a method of flow manipulation in microdevices, understanding the flow dynamics of multiple phases in microchannels is vital. However, experimental studies have thus far shown a great deal of variety in the flow patterns and instabilities that develop at the microscale level. Thus, numerical techniques capable of simulating such conditions are desirable. While traditional computational fluid dynamics (CFD) methods are based on macroscale equations, and molecular dynamics simulations seek to model the microscopic behavior of individual molecules, the LBM takes a mesoscopic approach. Based on the linearized kinetic lattice Boltzmann equation, particle interactions are directly implemented, while the movement of those particles is confined to a discrete lattice. This makes the LBM very useful in modeling interfacial dynamics and multiphase ows, while avoiding the enormous computational complexity of a direct MD simulation.;The novel contributions of this work are: a) the combination of the Peng-Robinson equation of state with a recently developed linear approximation of the interparticle interaction gradient for the improvement of the multiphase, single-component, thermal (MPSC-T) LBM, b) the development of a thermally-dependent wall interaction model for dynamic contact angle simulation in the MPSC-T LBM, c) an analysis of the stability region of the interparticle interaction parameters in a multiphase, immiscible, multicomponent, isothermal (MPiMCIT) model, and d) the development of a multiphase, immiscible, multicomponent, thermal (MPiMC-T) model using a density-weighted coupling of macroscopic properties.