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Complex coupled multi-physics simulations are playing increasingly important roles in scientific and engineering applications such as fusion plasma and climate modeling. At the same time, extreme scales, high levels of concurrency and the advent of multicore and many core technologies are making the high-end parallel computing systems on which these simulations run, hard to program. While the Partitioned Global Address Space (PGAS) languages is attempting to address the problem, the PGAS model does not easily support the coupling of multiple application codes, which is necessary for the coupled multi-physics simulations. Furthermore, existing frameworks that support coupled simulations have been developed for fragmented programming models such as message passing, and are conceptually mismatched with the shared memory address space abstraction in the PGAS programming model. This paper explores how multi-physics coupled simulations can be supported within the PGAS programming framework. Specifically, in this paper, we present the design and implementation of the XpressSpace programming system, which enables efficient and productive development of coupled simulations across multiple independent PGAS Unified Parallel C (UPC) executables. XpressSpace provides the global-view style programming interface that is consistent with the memory model in UPC, and provides an efficient runtime system that can dynamically capture the data decomposition of global-view arrays and enable fast exchange of parallel data structures between coupled codes. In addition, XpressSpace provides the flexibility to define the coupling process in specification file that is independent of the program source codes. We evaluate the performance and scalability of Xpress Space prototype implementation using different coupling patterns extracted from real world multi-physics simulation scenarios, on the Jaguar Cray XT5 system of Oak Ridge National Laboratory.

VORPAL enables researchers to simulate complex physical phenomena in less time and at a much lower cost than empirically testing process changes for plasma and vapor deposition processes. VORPAL offers a unique combination of physical models to cover the entire range of plasma simulation problems. Ionization and neutral gas models enable VORPAL to bridge the gap between plasma and neutral flow physics. VORPAL software runs on a wide range of computing platforms, from desktop machines to massively parallel supercomputers with thousands of processors. The use of standard data formats allows data analysis at various levels of sophistication, including your own preferred data analysis tool. VORPAL is used by scientists and engineers to simulate the physical behavior of devices and processes for many industrial and research applications, including laser wakefield accelerators, plasma thrusters, high-power microwave guides, and plasma processing chambers.

This paper describes the design of OpenFOAM, an object- oriented library for Computational Fluid Dynamics (CFD) and struc- tural analysis. Efficient and flexible implementation of complex physi- cal models in Continuum Mechanics is achieved by mimicking the form of partial differential equation in software. The library provides Fi- nite Volume and Finite Element discretisation in operator form and with polyhedral mesh support, with relevant auxiliary tools and sup- port for massively parallel computing. Functionality of OpenFOAM is illustrated on three levels: improvements in linear solver technology with CG-AMG solvers, LES data analysis using Proper Orthogonal Decom- position (POD) and a self-contained fluid-structure interaction solver.