DNS, filtered models and convergence evidence
Research context
research method · conditional · As of 2026-10-10
DNS aims to resolve the dynamically relevant viscous scales of a specified flow; LES filters resolved scales and models subfilter stress.
Key knowledge
DNS aims to resolve the dynamically relevant viscous scales of a specified flow; LES filters resolved scales and models subfilter stress. Changing resolution changes an LES filter/model problem as well as numerical error. Verification checks conservation, discretization and sampling; validation compares selected observables with independent uncertain measurements for the declared flow regime.
Conditions and scope
- Specify equation/constitutive model, boundary and initial conditions, mesh/time step, filter and averaging interval; no universal cells-per-flow rule.
- Check balances and resolved spectra, multiple space/time resolutions, wall treatment and sampled uncertainty. Richardson estimates require an asymptotic regime and do not remove closure error.
Sources · 4
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
NASA Glenn / NPARC Alliance2 sources
- Reynolds averaging · Aerodynamics lecture 26 (2005)David Darmofal / MIT OpenCourseWareCourse notes · PDF
- Turbulence Models and Their Application to Complex Flows · Revision 4.01R. H. Nichols / University of Alabama at Birmingham; NASA-hosted referenceReference guide · PDF
Evidence and review
Inspected grid refinement, observed order, asymptotic-range check and Richardson extrapolation; historical tutorial, not a statement that no modern standards exist; source check dated 2026-10-10. Scope is limited to the cited statements, equations and assumptions, not the whole publication. Inspected calculation verification and comparisons with uncertain experimental observables for a declared application; source check dated 2026-10-10. Scope is limited to the cited statements, equations and assumptions, not the whole publication. Inspected all three pages: Reynolds decomposition, averaged incompressible equation and extra stress closure; source check dated 2026-10-10. Scope is limited to the cited statements, equations and assumptions, not the whole publication. Inspected §§1.6, 8.0–8.2 and 8.8: DNS resolution, spatial filtering/subgrid terms and specific mixing-layer validation; historical reference rather than contemporary computer-capacity claim; source check dated 2026-10-10. Scope is limited to the cited statements, equations and assumptions, not the whole publication.
2026-10-10 · Author source inspection of the displayed claim, model assumptions and equations; independent exact-content and branch-inventory review is a separate gate. Contemporary status is a dated snapshot, not a promise of ongoing monitoring.
Entry details
Permanent link to this entry ↗- Record identity
- research-physics-turbulent-simulation-validation
- Revision
- research.1
- Structured reference record
- Postgraduate & research reference