dragervlak

Dragervlak is a term used primarily in Dutch-language sources to denote a planar reference surface associated with aerodynamic or hydrodynamic drag. The word is a compound of drag-er (carrier or the act of dragging) and vlak (plane). In English-language literature, the term is not standard and does not have a single accepted definition. In technical discussions, dragervlak may refer to a hypothetical plane perpendicular to the flow on which drag forces are computed or resolved, serving as a cross-sectional reference for decomposing drag into components such as pressure drag and skin-friction drag. In computational fluid dynamics (CFD) or wind tunnel analyses, the dragervlak can serve as a diagnostic plane for evaluating pressure distribution and resultant forces on a body.

Usage and scope vary, and some sources describe dragervlak as part of simplified modeling approaches where a complex three-dimensional surface drag is projected onto a two-dimensional plane to facilitate analysis. It remains a niche term and is not widely used across engineering disciplines.

Origin and regional usage: The term appears mainly in Dutch technical writing; in international literature, equivalent concepts are usually referred to as reference planes or cross-sectional planes for drag analysis. See also: drag coefficient, drag force, reference plane, CFD.