# Qualitative Benchmarks

MFIX-Exa uses a three level approach to regression testing spanning from simple and/or short smoke tests to validation problems comparing against experimental data. Most of the validation benchmarks target the physics of interest to MFIX-Exa’s intended audience, i.e., dense bubbling, fast fluidization and pneumatic transport of particulate solids by a light gas. In an effort to widen the phase-space in which MFIX-Exa may be (potentially) applied, a set of qualitative benchmark problems are provided below which focus more on the phenomenology of a given, problem rather than averaged statistical measures. Animations of numerical soluitons to several of the qualitative benchmarks can be seen in the Gallery

- Clustering in the HCS
- Granular Rayleigh-Taylor
- Mehrdad’s Bed
- Single Bubble Injection
- Bidisperse Segregation
- References