Experimental and computational flow analyses of a confined jet impinging on a flat plate

This paper presents and compares experimental and computational fluid flow data for a single jet issued from a circular pipe and impinging orthogonally on a flat plate. The jet was confined in a cylindrical domain with perpendicular walls 7.5 pipe diameters away from the jet centerline. Three-component, time-averaged velocity measurements were obtained in three dimensions at several million locations using Magnetic Resonance Velocimetry (MRV). The impinging jet flow was fully turbulent with a Reynolds number of 23,000 based on the pipe diameter. The separation distance between the plate and the jet exit plane was two jet diameters. In this study, experimental data from MRV are compared with Reynolds-averaged Navier Stokes (RANS) simulations and Improved Delayed Detached Eddy Simulations (IDDES) using the ANSYS Fluent flow solver and four different RANS turbulence models. Radial velocity profiles at distances of one and two diameters away from the centerline are found to agree well with the MRV data and hot-wire anemometry experiments from the literature completed for an unconfined case (Cooper et al., Int. J. Heat Mass Transer 36, 2675 (1993)). As the radial distance increases, the MRV and the hot-wire results diverged only slightly, and are generally within the experimental uncertainty for the MRV data. The k-ω shear stress transport (SST) hybrid turbulence model showed the best overall agreement with the experimental data and was the only simulation that captured the wall jet shear layer thickness beyond one diameter from the jet centerline location. The utility of the MRV data as a validation set for this classically studied flow is presented for the modeling and simulation community.