An Experimental Study of Homogeneous Anisotropic Turbulence in Channel Flow

A novel high bleed blown jet grid turbulence generator has been developed and tested in both a small-scale divergent duct and subsonic wind tunnel facility developed for flame kernel studies. The small-scale divergent duct is shown to produce an experimental realization of homogeneous turbulence that is comparable to traditional larger turbulence facilities. The high-bleed blown jet grid is shown to produce high Reλ turbulence, with 90 < Reλ < 298 for tunnel total mass flow bleed ratios ranging from 10% to 30%. The resultant turbulence is comparable to that achieved by active vane grids, however the blown jet grid produces such results at grid mesh Reynolds number ReM ≤ 6580, which is less than half of what is observed for similar turbulence generated by active vane grids. Turbulence generated under shared inflow conditions as the divergent duct study are evaluated in the subsonic facility configuration. The “High Contraction Ratio” anomaly is identified and analyzed, enabling measures for its removal from future turbulence studies in the subsonic facility.