skip to main content


Title: An efficient FLIP and shape matching coupled method for fluid–solid and two-phase fluid simulations
Award ID(s):
1715985
NSF-PAR ID:
10297703
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
The Visual Computer
Volume:
35
Issue:
12
ISSN:
0178-2789
Page Range / eLocation ID:
1741 to 1753
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. null (Ed.)
    Crystallization of the 2.06 Ga Bushveld magma formed a 9 km (maximum) sequence of ultramafic and mafic rocks that generated a large volume of country fluid as it thermally metamorphosed a 3+ km section of previously unaltered underlying sedimentary rocks of the Transvaal sequence – a geometry similar to that seen as subducting lithospheric slabs are heated by overlying mantle rocks. The presence of a diatreme (breccia pipe) and other large, pipe-like features in the Bushveld Complex located proximal to diapiric upwelling of the basement rocks suggest that overpressured fluids generated during dehydration of the footwall sediments are focused by the diapiric structures such that the country fluids rapidly penetrate the Bushveld rock. A re-examination of existing stable and radiogenic isotopic evidence is consistent with contamination of Main Zone magmas by 1–2% country fluid. Numeric modelling of the footwall dehydration similarly shows that most of the country fluids will be confined to pipe-like channels as it percolates into the Bushveld sill. Modelling also suggests that the maximum extent of the metamorphic aureole was reached at about the same time that the Main Zone began to crystallize. It is proposed that rapid inflation of the Bushveld sill induced the sudden and catastrophic expulsion of overpressured country fluids to both generate the diatreme and contaminate the Main Zone magma, resulting in the Main Zone enrichment in crustal stable and radiogenic isotopic signatures (Sr, Nd, O and others). By analogy, it is also suggested that hydration melting in the mantle wedge is episodically driven by similar sudden influxes of slab fluids that are able to retain their geochemical and isotopic character by rapid channelled influx. This can be aided by flow focusing at diapirs structures at the upper slab-mantle contact. 
    more » « less
  2. We present a detailed guide to advanced collisionless fluid models that incorporate kinetic effects into the fluid framework, and that are much closer to the collisionless kinetic description than traditional magnetohydrodynamics. Such fluid models are directly applicable to modelling the turbulent evolution of a vast array of astrophysical plasmas, such as the solar corona and the solar wind, the interstellar medium, as well as accretion disks and galaxy clusters. The text can be viewed as a detailed guide to Landau fluid models and it is divided into two parts. Part 1 is dedicated to fluid models that are obtained by closing the fluid hierarchy with simple (non-Landau fluid) closures. Part 2 is dedicated to Landau fluid closures. Here in Part 1, we discuss the fluid model of Chew–Goldberger–Low (CGL) in great detail, together with fluid models that contain dispersive effects introduced by the Hall term and by the finite Larmor radius corrections to the pressure tensor. We consider dispersive effects introduced by the non-gyrotropic heat flux vectors. We investigate the parallel and oblique firehose instability, and show that the non-gyrotropic heat flux strongly influences the maximum growth rate of these instabilities. Furthermore, we discuss fluid models that contain evolution equations for the gyrotropic heat flux fluctuations and that are closed at the fourth-moment level by prescribing a specific form for the distribution function. For the bi-Maxwellian distribution, such a closure is known as the ‘normal’ closure. We also discuss a fluid closure for the bi-kappa distribution. Finally, by considering one-dimensional Maxwellian fluid closures at higher-order moments, we show that such fluid models are always unstable. The last possible non Landau fluid closure is therefore the ‘normal’ closure, and beyond the fourth-order moment, Landau fluid closures are required. 
    more » « less