In this paper we report on the results of a joint eeort of astrophysicists and computer scientists to develop and implement a parallel program that enables us to solve large systems of hydrodynamic equations and covers a wide range of applications in astrophysics. We introduce the Distributed Threads System (DTS) as an environment for the development of portable parallel applications. The numer...

a r t i c l e i n f o a b s t r a c t We present a methodology to concurrently couple particle-based methods via a domain decomposition (DD) technique for simulating viscous flows. In particular, we select two resolutions of the smoothed particle hydrodynamics (SPH) method as demonstration. Within the DD framework, a simulation domain is decomposed into two (or more) overlapping sub-domains, ea...

We model a massless viscous disk using Smoothed Particle Hydro-dynamics (SPH) and note that it evolves according to the Lynden-Bell & Pringle theory (1974) until a non-axisymmetric instability develops at the inner edge of the disk. This instability may have the same origin as the instability of initially axisymmetric viscous disks discussed by Lyubarskij et al. (1994). To clarify the evolution...

In this review the basic principles of smooth particle hydrodynamics (SPH) are outlined in a pedagogical fashion. To start, a basic set of SPH equations that is used in many codes throughout the astrophysics community is derived explicitly. Much of SPH’s success relies on its excellent conservation properties and therefore the numerical conservation of physical invariants receives much attentio...

In this study, we present the DEM-SPM method, a Lagrangian-Lagrangian coupled algorithm, for simulating solid-liquid flows involving free surfaces. The DEM solid phase and the SPH liquid phase are connected using the local averaging technique, where the governing equations are modeled taking account of the local mean voidage. Conservative forms of momentum balance are derived via a variational ...

Streptococcus pyogenes protein H (sph) is an immunoglobulin-binding protein present in the Mga regulon of certain M1 serotype isolates. Although sph is present in many strains, it is frequently not expressed. In this paper we show that protein H was highly expressed after bacteria were injected into the skin of mice and were recovered from the blood, kidney, or spleen at various times postinfec...

With the improvement of Smoothed Particle Hydrodynamic (SPH), it has become one of most vigorous methods for breaking wave simulation. Recently we have developed an improved SPH method for simulating violent flow and wave impact to different angle slopes. The main features of the new method include the incompressible SPH method based the incompressible Poisson equation, and it also gives a new ...

We present results from a Smoothed Particle Hydrodynamic (SPH) simulation of galaxy formation that exceeds the minimum resolution requirement suggested by Steinmetz & Muller (1993) of 3 × 10 SPH particles per galaxy. Using the multiple mass technique an effective resolution of a little over one billion particles is attained within a 48 Mpc cube. We find that even with an SPH mass resolution of ...

The focus of the research activity is on the Smoothed Particle Hydrodynamics (SPH) method and its applications to environmental flow problems. The purpose is to model fully three-dimensional non-hydrostatic free surface flows and impact problems with the SPH method applying it to inviscid and viscous fluids. After a thorough literature review of the SPH method, the research work is divided up i...

We introduce a modified SPH approach that is based on discretising the particle density instead of the mass density. This approach makes it possible to use SPH particles with very different masses to simulate multi-phase flows with large differences inmass density between the phases.We test our formulationwith a simple advection problem, with sound waves encountering a density discontinuity, an...