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A low speed, closed loop wind tunnel at Texas A&M University is presented for the study of turbulent mixing produced by a variety of flows types. Anticipated experiments range from canonical “unit flows” to more complex combinations of flows and geometries. Originally located at the University of Pittsburgh, the facility has since been re-located to the Thermal Hydraulics Verification and Validation (THVV) laboratory at Texas A&M University. The tunnel has undergone considerable modification and updated diagnostics prompting renewed interest in flow quality assessment. This includes a thorough mapping of the tunnel inlet velocity profile provided by Particle Image Velocimetry (PIV) measurements. Additional temperature and gage pressure measurements complete the assessment of system capabilities. These preliminary diagnostics yield empirically determined boundary conditions and fluid property correlations necessary for Computational Fluid Dynamics (CFD) model validation. The article concludes with the presentation of two unit flow types, including flow past a cylinder, with three distinct cross sections, and a single round jet in cross flow at three velocity ratios. The unit flows serve as initial benchmarks for THVV simulation efforts. Key validation metrics are presented for each benchmark including ensemble averaged velocities, Reynolds stresses, and proper orthogonal decomposition (POD) eigenvectors.

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Jet impingement onto a solid boundary is of practical interest in a variety of engineering applications. The novelty of the current work is in the comparison of the single and multiple inline jets, the latter being more prevalent in application but less examined in the literature. The study focuses explicitly on the incompressible, hydraulic comparison, by performing experiments near room temperature and low speeds. Three round jets of diameter 22.23 mm are placed inline and 2 diameters apart on the ceiling of the test section. The jets issue vertically downward into a pseudo-unconfined domain whose bottom surface is 9.8 diameters from the jet outlets, acting as the plate. Three distinct flow rates are measured via Stereoscopic Particle Image Velocimetry (S-PIV) for both the single jet and triple jet geometries, where for the latter, each outlet is set to an equivalent flow rate. Several reference parameters further delineate fluid properties in the test section and ambient environment. The investigation begins with evaluation of the single jet, comparing first and second order turbulence statistics with existing literature. The triple jet cases are then presented, showing dramatically different behavior. The results of each configuration, inlet profiles, reference parameters, and uncertainty quantification are provided to embolden future work in computational fluid dynamics (CFD). The investigation concludes with the promotion of several comparisons of the single and triple jet setup and is meant to provide insight into the expected dynamic response of the fluid near and along the solid boundary.