WP D - Multiphase and Complex Fluid Applications

Lead: Tim Phillips

Lattice Boltzmann Methods for Multiphase Flow

Lattice Boltzmann methods are continually being developed for multiphase flow to cover the full range of physical parameters (such as the density ratio, Reynolds number, Weber number, capillary number, Ohnesorge number). Recent efforts have been focused on improving Shan-Chen pseudopotential models and obtaining high-order models such as the cascaded LBM. Multicomponent LBMs are also being developed.

Lattice Boltzmann Methods for Non-Newtonian and Viscoelastic Fluids

Most existing macroscopic models for viscoelastic fluids fail at high fluid elasticity. Whereas models based on kinetic theory are much more robust, they are computationally expensive due to the size of configuration space. Work in the UKCOMES is focused on developing efficient and accurate LBMs for non-Newtonian and viscoelastic fluids in which conventional LBM treatment of Newtonian fluids is coupled to a treatment of the rheological equation of state. A considerable amount of experimental data has been used to benchmark LBM predictions for viscoelastic flow problems such as flow past a cylinder or sphere and flow through contraction geometries

Complex Fluids simulation

Current activities include (i) predictive modelling of dynamic wetting phenomena; (ii) industrial inkjet printing, where colloidal suspensions are used for additive manufacture; (iii) separation of water from diesel (especially biodiesel, where surfactants lead to low interfacial tensions) via fuel filtration systems; (iv) enhanced oil recovery, where alteration of rock wettability and direct simulation of multiphase flow through actual pore structures is vital; (v) nanofluid modeling for enhanced cooling applications; and (vi) computational tribology, where the aim is to develop predictive models of tribofilm formation (and surface wear) to enable development of environmentally friendly lubrication systems for internal combustions engines to reduce emissions and improve efficiency; and (vii) flow control using pulsed electric fields.