In this paper we evaluate the performance of Unified Parallel C (which implements the partitioned global address space programming model) using a numerical method that is widely used in fluid dynamics. In order to evaluate the incremental approach to parallelization (which is possible with UPC) and its performance characteristics, we implement different levels of optimization of the UPC code an...

This paper is concerned with the implementation of a three-dimensional unstructured-grid Euler-solver on massively parallel distributed-memory computer ar-chitectures. The goal is to minimize solution time by achieving high computational rates with a numerically eecient algorithm. An unstructured multigrid algorithm with an edge-based data-structure has been adopted, and a number of optimizatio...

This work develops a new open source application programming interface (API) and software package called SymPhas for simulations of phase-field, phase-field crystal, reaction-diffusion models, supporting up to three dimensions an arbitrary number fields. delivers two novel program capabilities: 1) User specification models from the associated dynamical equations in unconstrained form 2) extensi...

We derive novel, fast, and effective preconditioned iterative methods for steady time-dependent Navier--Stokes control problems. Our approach may be applied to problems which are discretized using backward Euler or Crank--Nicolson is also a valuable candidate Stokes Crank--Nicolson. The key ingredients of the solver saddle-point type approximation linear systems, an inner iteration $(1,1)$-bloc...

We report on recent work on adaptive timestep control for weakly instationary gas flows [16, 18, 17] carried out within SFB 401, TPA3. The method which we implement and extend is a space-time splitting of adjoint error representations for target functionals due to Süli [19] and Hartmann [10]. In this paper, we first review the method for scalar, 1D, conservation laws. We design a test problem f...

In this study, we consider a variant of the hybrid parareal algorithm based on deferred correction techniques in order to increase the convergence order even for the stiff system. A hybrid parareal scheme introduced by Minion (2011) [20] improves the efficiency of the original parareal by utilizing a Spectral Deferred Correction (SDC) strategy for a fine propagator within the parareal iteration...

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

Previously, Chang reported a new high-order Conservation Element Solution Element (CESE) method for solving nonlinear, scalar, hyperbolic partial differential equations in one dimensional space. Bilyeu et al. have extended Chang’s scheme for solving a onedimensional, coupled equations with an arbitrary order of accuracy. In the present paper, the one-dimensional, high-order CESE method is exten...

An approach that uses gridless or meshless methods to address the problem of boundary implementation associated with the use of Cartesian grid is discussed. This method applies the gridless concept only at the interface, whereas a standard structured grid method is used everywhere else. The Cartesian grid is used to specify and distribute the computational points on the boundary surface but not...