Active grids enable the controlled generation of high Reynolds number turbulence; however, the influence of inlet conditions in the near-grid region remains poorly understood. Here we present a physics-focused experimental study of active-grid-generated turbulence in a water tunnel, focusing on the near-grid region ($x/M<20$), where the flow remains approximately homogeneous but strongly anisotropic. Inlet conditions are varied by independently controlling the operating protocol, the global blockage ratio (25%–74%), the mesh Reynolds number ($\mathrm{Re}{}_{\mathrm{M}}$), and the Rossby number (Ro). At the highest global blockage (74%), trends in large-scale statistics with $\mathrm{Re}{}_{\mathrm{M}}$ and Ro are consistent with measurements reported farther downstream in the literature. In contrast, at substantially lower blockages (≲40.2%), qualitatively different behavior emerges: turbulence intensity decreases monotonically with increasing $\mathrm{Re}{}_{\mathrm{M}}$ and exhibits little sensitivity to Ro. These results demonstrate that global blockage acts as a contributing parameter for the persistence of inlet-condition effects, whereas $\mathrm{Re}{}_{\mathrm{M}}$ and Ro modulate the redistribution of energy across scales. While large-scale quantities differ at lower global blockage relative to the far-grid region, the dissipative length scale exhibits consistent trend with $\mathrm{Re}{}_{\mathrm{M}}$ and Ro across all blockages. Despite persistence of inlet condition in the near-grid region, streamwise velocity spectra exhibit collapse at low and high wave numbers when scaled by the integral and Kolmogorov length scales, respectively, indicating that two distinct length scales are required to describe the near grid. Together, these findings provide insight into how forcing geometry and timescales influence the transition from forcing-dominated toward more universal turbulence behavior, and establish global blockage as an important parameter controlling near-grid active-grid turbulence.

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• Flow control
• Turbulence