Papers & Reports 2002

Using standard duality arguments, we construct exact error representation formulas for derived functionals that are tailored to the class of high order Godunov finite volume methods with data reconstruction. We then devise computable error estimates that exploit the structure of Godunov finite volume methods.
A Posteriori Error Estimates for Higher Order Godunov Finite Volume Methods on Unstructured Meshes,NAS Technical Report, NAS-02-001, February 2002.

THis report describes a two level parallelization of a computational fluid dynamics solver with multi-zone overset structured grids. THe approach is based on a hyprid MPI+OpenMP programming model suitable for shared memory and clusters of shared memory machines.
Hybrid MPI OpenMP Programming of an Overset CFD Solver and Performance Investigations,NAS Technical Report, NAS-02-002, May 2002.

Computational grids provide users with many possible places to execute their applications. We wish to help users select where to run their applications by providing predictions of the execution times of applications on space shared parallel computers and predictions of when scheduling systems for such parallel computers will start applications.
Resource Selection Using Execution and Queue Wait Time Predictions,NAS Technical Report, NAS-02-003, July 2002.

We present new third- and fifth-order Godunov-type central schemes for approximating solutions of the Hamilton-Jacobi (HJ) equation in an arbitrary number of space dimensions. These are the first central schemes for approximating solutions of the HJ equations with an order of accuracy that is greater than two.
High-Order Central WENO Schemes for Multi-Dimensional Hamilton-Jacobi Equations,NAS Technical Report, NAS-02-004, July 2002.

We provide a paper-and-pencil specification of a benchmark suite for computational grids. It is based on the NAS Parallel Benchmarks (NPB) and is called the NAS Grid Benchmarks (NGB). NGB problems are presented as data flow graphs encapsulating an instance of a slightly modified NPB task in each graph mode, which communicates with other nodes by sending/receiving initialization data.
NAS Grid Benchmarks Version 1.0,NAS Technical Report, NAS-02-005, July 2002.

We present the first fifth-order, semi-discrete central-upwind method for approximating solutions of multi-dimensional Hamilton-Jacobi equations. Unlike most of the commonly used high-order upwind schemes, our scheme is formulated as a Godunovtype scheme.
High-Order Semi-Discrete Central-Upwind Schemes for Multi-Dimensional Hamilton-Jacobi Equations,NAS Technical Report, NAS-02-006, July 2002.

We describe a new problem size, called Class D, for the NAS Paralell Benchmarks, whose MPI source code implementation is being released as NPB 2.4. A brief rationale is given for how the new class is derived.
NAS Parallel Benchmarks, Version 2.4,NAS Technical Report, NAS-02-007, October 2002.

We present an evaluation of the efficiency and the scalability of an explicit CFD operator on an IBM POWER4 system.
The Efficiency and the Scalability of an Explicit Operator on IBM POWER4 System,NAS Technical Report, NAS-02-008, August 2002.

Several features make Java an attractive choice for high performance computing. In order to gauge the applicability of Java to computational fluid dynamics (CFD), we have implemented the NAS Parallel Benchmarks in Java. The performance and scalability of the benchmarks point out the areas where improvement in Java compiler technology and in Java thread implementations would position Java closer to Fortran in the competition for CFD applications.
Implementation of the NAS Parallel Benchmarks in Java,NAS Technical Report, NAS-02-009, November 2002.