Multipseudopotential interaction : a lattice Boltzmann scheme for simulation of multiphase flows

In this study, a new pseudopotential Lattice Boltzmann (LB) scheme, multipseudopotential interaction (MPI), including boundary conditions is proposed for simulation of two-phase flows. It solves several drawbacks of available schemes such as being thermodynamically inconsistent with practical equations of state (EOSs), being limited to low-density ratios, not having an independently tunable interface width. The lattice interaction potential is described by a series of consistent sub-potentials. In theory, in addition to being intrinsically consistent with thermodynamics, the MPI-LB scheme is stable for a large range of density ratios (up to 106), and tunable for interface width. In engineering applications, the scheme is superior over the previous schemes of reproducing practical EOSs by removing the deficiency of creating unphysical potentials. The scheme is unlimited to implement the practical EOSs which can be expressed in a polynomial format. The scheme is studied and verified regarding liquid vapour circular and flat interfaces, Laplace law, Galilean invariance, and change of viscosity. Furthermore, the scheme is investigated for the effects of different wall boundary conditions on the hydrodynamics of non-ideal single-phase fluids. The suitable boundary condition is chosen based on density variation across the channel, and errors because of domain resolution, relaxation time, and compressibility

Force-Chain Finder: A software tool for the recursive detection of force-chains in granular materials via minor principal stress

Force transmission in granular media occurs through an inhomogeneous network of inter-particle contacts referred to as force-chains. A thorough understanding of the structure of these chains is indispensable for a better comprehension of the macroscopic signatures they generate. This paper introduces Force-Chain Finder (FCF), an open-source software tool designed for detecting force-chains in granular materials. Leveraging the stress tensor computed for each particle based on its interactions with neighboring particles, the tool effectively identifies the magnitude and direction of the most compressive principal stress. Through a recursive traversal of particles and their neighbours, force-chains are robustly detected based on the alignment of the principal stress directions, which is decided by a parameter α (an angle in radians). The software provides a comprehensive suite of post-processing features, including the exportation of results in different formats, enabling detailed analysis of specific regions and dynamic phenomena. Additionally, the software facilitates the computation of statistical measures pertaining to chain size and population. By streamlining the identification and characterization of force-chains within discrete element method (DEM) simulations, this tool significantly enhances the efficiency and accuracy of force-chain analysis. Thus, the software promotes deeper insights into the behaviour of granular materials by enabling researchers to effortlessly detect and analyse force-chains

Ensuring efficient and robust offshore storage – The role of marine system modelling

This paper describes the utility of developing marine system models to aid the efficient and regulatory compliant development of offshore carbon storage, maximising containment assurance by well-planned monitoring strategies. Using examples from several model systems, we show that marine models allow us to characterize the chemical perturbations arising from hypothetical release scenarios whilst concurrently quantifying the natural variability of the system with respect to the same chemical signatures. Consequently models can identify a range of potential leakage anomaly detection criteria, identifying the most sensitive discriminators applicable to a given site or season. Further, using models as in-silico testbeds we can devise the most cost-efficient deployment of sensors to maximise detection of CO2 leakage. Modelling studies can also contribute to the required risk assessments, by quantifying potential impact from hypothetical release scenarios. Finally, given this demonstrable potential we discuss the challenges to ensuring model systems are available, fit for purpose and transferable to CCS operations across the globe

A study of wall boundary conditions in pseudopotential lattice Boltzmann models

A study of wall boundary conditions in pseudopotential lattice Boltzmann model