In this paper, we study the flow field characteristics of a turbulent flow over a regularized cube array with a perpendicular injection flow through the floor between the second and third cubic, representing a complex flow interactions of a three-dimensional jet and wake flows behind cubical obstacles. Four different experimental measurements were performed featuring two magnetic resonance imaging (MRI)-based measurements for three-dimension three-component (3D3C) velocity (MRV) and concentration (MRC), and two laser-based techniques, such as particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF) for 2D2C velocity and concentration measurement, respectively. The mainstream Reynolds number is $Re = 15,000$, based on the primary inlet velocity $U_m$ and channel height $D_H$, while the injector Reynolds number is $Re_j = 3,400$, based on the injector velocity $U_j$ and the injector's exit width $D_j$. Numerical simulations are performed for the studied flow configuration of turbulent flow over a regularized cube array using Reynolds-averaged Navier-Stokes (RANS) and large-eddy simulation (LES) approaches. Results obtained from experimental measurements, including MRV, MRC, PIV, and PLIF, and RANS and LES simulations are discussed and compared along several horizontal and vertical planes of the studied configuration. In addition, 3D turbulent flow structures, such as leading-edge vortex, horseshoe vortex, and jet shear-layer vortex, and the isosurfaces of scalar concentration successfully revealed by MRV and MRC techniques are found to be in very good agreement with those 3D features extracted from RANS and LES simulations. The high-resolution experimental and numerical database obtained from this study could be useful for validation and verification of numerical codes
