Robustness of numerical methods has attracted an increasing interest in the community of computational fluid dynamics. One mathematical aspect of robustness for numerical methods is the positivity-preserving property. At high Mach numbers or for flows near vacuum, solving the conservative Euler equations may generate negative density or internal energy numerically, which may lead to nonlinear i...

In the physically inviscid fluid dynamics, ”shock capturing” methods adopt either an artificial viscosity contribution or an appropriate Riemann solver algorithm. These techniques are necessary to solve the Euler equations if flow discontinuities (the Riemann problem) must be solved. A necessary dissipation is normally used in such cases. An explicit artificial viscosity contribution is normall...

Algebraic flux correction schemes of TVD and FCT type are extended to systems of hyperbolic conservation laws. The group finite element formulation is employed for the treatment of the compressible Euler equations. An efficient algorithm is proposed for the edge-by-edge matrix assembly. A generalization of Roe’s approximate Riemann solver is derived by rendering all off-diagonal matrix blocks p...

The Implicit Continuous-fluid Eulerian (ICE) method is a successful and widely used semi-implicit finitevolume method that applies to flows that range from supersonic to subsonic regimes. The classical ICE method has been expanded to problems in multiphase flow which span a wide area of science and engineering. The ICE method is utilized by the C-SAFE code Uintah written at the University of Ut...

Abstract In dredging applications, deep sea mining and land reclamation projects typically large amounts of sediments are transported through pipes in the form hyper concentrated (40% sediment or more) sediment-water mixtures slurries. this paper it is investigated how well a generic Euler-Euler CFD-model capable to model velocity, concentration profiles pressure gradient above deposition limit...

This work focuses on the derivation and analysis of a novel, strongly-coupled partitioned method for fluid–structure interaction problems. The flow is assumed to be viscous incompressible, structure modeled using linear elastodynamics equations. We assume that thick, i.e., same number spatial dimensions as fluid. Our newly developed numerical based Robin boundary conditions, well refactorizatio...

This study focuses on modelling and simulation of horizontal moving bed/grate wood chip combustor. A standalone finite volume based 2-D steady state Euler-Euler Computational Fluid Dynamics (CFD) model was developed for packed bed combustion. Packed bed combustion of a medium scale biomass combustor, which was retrofitted from wood log to wood chip feeding for Tea drying in Sri Lanka, was evalu...

In this paper, we study a time discrete scheme for the initial value problem of the ES-BGK kinetic equation. Numerically solving these equations are challenging due to the nonlinear stiff collision (source) terms induced by small mean free or relaxation time. We study an implicit-explicit (IMEX) time discretization in which the convection is explicit while the relaxation term is implicit to ove...

A large-scale, real-world application of Evolutionary MultiCriterion Optimization (EMO) is reported in this paper. The Multidisciplinary Design Optimization among aerodynamics, structures and aeroelasticity for the wing of a transonic regional jet aircraft has been performed using high-fidelity models. An Euler/Navier-Stokes (N-S) Computational Fluid Dynamics (CFD) solver is employed for the ae...

high-resolution time conservative two dimensional flow solver has been developed and validated for inviscid and viscous flows. The method is based on a multiblock structured grid. The space-time conservation element and solution element discretization scheme, second-order in space and time, is employed. Several cases with a wide range of flow conditions have been computed to verify the accuracy...