John Tramm

Results 28 issues of John Tramm

The multigroup mode for OpenMC currently does not scale very well when run using shared memory threading (via OpenMP) past 10 threads or so. For example, on [this 2D C5G7...

Performance
Multi-Group Mode

The STL function `memcmp()` does not appear to be available on device. While much of the STL is not expected to be present for device regions, typically simple functions like...

# Introduction of Basic Random Ray Solver Mode in OpenMC ## What is Random Ray? Random ray is a stochastic transport method, closely related to the deterministic Method of Characteristics...

Random Ray

In addition to the usual geometry plotting capabilities available with `openmc --plot`, the random ray solver also is capable of outputting result data (e.g., flux, source, etc) at the end...

Random Ray

Performance of the random ray solver in OpenMC is highly sensitive to the performance of the flux attenuation kernel that forms the inner loop of the simulation. This inner loop...

Performance
Random Ray

Similar to Monte Carlo, computation of Shannon Entropy is a useful way to determine if enough inactive batches have been run such that the source has fully developed and become...

Random Ray

Currently the documentation on the random ray solver is nearly non-existent. The only documentation is some terse discussion on the settings themselves, with no overview of what the solver, how...

Documentation
Random Ray

This feature will utilize the random ray solver (with adjoint) to generate weight windows via the FW-CADIS method for use with Monte Carlo. A primary intended use case is for...

Random Ray

Adjoint solutions are generally very easy to generate with random ray, basically just requiring the transposition of the scattering matrix but otherwise performing transport as normal. Adjoints have a number...

Random Ray

While OpenMC currently has a cylindrical filter mesh type, it does not have a more basic lattice geometry abstraction. For typical PWR pincell geometries with fuel/gap/clad, cell find routines may...

Performance
Random Ray