Verification and Validation of CFD Based Turbulent Flow Experiments

Abstract

Accurate predictions with quantifiable uncertainty are essential to many practical flow applications exhibiting extreme geometrical complexity and broad ranges of length and time scales. Under‐resolved computer studies are typically unavoidable in such applications. Critical issues involved in the flow experiments based on computational fluid dynamics relate to the treatment of unresolved subgrid scale flow features and required initial and boundary condition supergrid scale modeling. Flow characterization issues become very challenging ones in validation exercises based on laboratory data where potential sources of discrepancies between predictions and measurements need to be clearly evaluated and controlled. A special focus of the discussion in this chapter is devoted to turbulent flows. The inherently intrusive nature of numerical and laboratory turbulent flow experiments is noted in this context .

LES validation of urban flow, part I: flow statistics and frequency distributions

“…A model is validated in order to determine whether its combination of conceptual and computational components allow an accurate simulation of the physical problem of interest from the perspective of a specific application [1,25,47]. Model validation primarily depends on two essential factors: the availability of suitable reference data [37] and the application of comparison strategies for model-specific performance assessments [57,47,4].…”