Direct Investigation of Nonlinear and Nonlocal Turbulent Constitutive Relations in a Three-Dimensional, Non-Equilibrium Boundary Layer

The Benchmark Validation Experiment for RANS and LES Investigations (BeVERLI) is examined for insights into the behavior and physical relevance of turbulent constitutive relations in a three-dimensional, pressure-driven boundary layer flow. In particular, the role of nonlinearity and nonlocality as competing or joint arguments for the modeling of three- dimensional turbulent boundary layers is explored. The following constitutive relations are thereby directly investigated using particle image velocimetry flow field velocity data from the BeVERLI wind tunnel experiments: the standard Boussinesq approximation [1], the quadratic constitutive relation (QCR) [2–4], and the difference-quotient model [5, 6]. The results suggest that the shape of the Reynolds stress anisotropy and its development history most prominently affect the applicability of the tested turbulent constitutive relations in three-dimensional boundary layer flows. The QCR model consistently shows an improved applicability over the other tested models for the considered curvature and pressure gradient combinations imposed to the measured boundary layer over the BeVERLI Hill.