A Semi-explicit Large Eddy Simulation (SeLES) is proposed to help handle interactions between discontinuities and turbulence when using conventional Sub-Grid Scale (SGS) models of large eddy simulation. For the grid-scale simulation, numerical viscosity becomes effective in limited region detected by discontinuity sensor, whereas a central difference scheme applied elsewhere. In our SeLES, disc...

The one dimension computational model of a sequential injection engine, which runs on compressed natural gas (CNG) with spark ignition, is developed for this study, to simulate the performance of gas flow pressure profile, under various speed conditions. The computational model is used to simulate and study of the steady state and transient processes of the intake manifold. The sequential injec...

The performance of farming systems models for grazed grasslands are seldom evaluated against comprehensive field data. aim this study was to evaluate the capacity a daily time step, grazing simulation model—the SGS (Sustainable Grazing Systems) Pasture Model—to simulate production and aspects sustainability. This completed by evaluating temporal changes in soil water balance, some major nitroge...

For jets, large eddy resolving simulations are compared for a range of numerical schemes with no subgrid scale (SGS) model and for a range of SGS models with the same scheme. There is little variation in results for the different SGS models, and it is shown that, for schemes which tend towards having dissipative elements, the SGS model can be abandoned, giving what can be termed numerical large...

In this work coherent vortex simulation (CVS) and stochastic coherent adaptive large eddy simulation (SCALES) simulations of decaying incompressible isotropic turbulence are compared to DNS and large eddy simulation (LES) results. Current LES relies on, at best, a zonally adapted filter width to reduce the computational cost of simulating complex turbulent flows. While there is an improvement o...

Abstract It is often not appreciated that forecast ensembles are generally skewed. The skew can arise from the state dependence of chaotic system dynamics responsible for ensemble spread. Generation by this mechanism be demonstrated in even simplest dynamical with state‐dependent noise, and when initial asymptotic (i.e., “climatological”) distributions both symmetric. Indeed, systems noise tend...

The traditional approaches of modeling and estimation of highly skewed deposits have led to incorrect evaluations, creating challenges and risks in resource management. The low concentration of the rare earth element (REE) deposits, on one hand, and their strategic importance, on the other, enhances the necessity of multivariate modeling of these deposits. The wide variations of the grades and ...

Explicit filtering has the effect of reducing numerical or aliasing errors near the grid scale in large eddy simulation (LES). We use a differential filter, namely the inverse Helmholtz operator, which is readily applied to unstructured meshes. The filter is invertible, which allows the sub-filter scale (SFS) stresses to be exactly reconstructed in terms of the filtered solution. Unlike eddy vi...