Analyses were made on a homogeneous turbulence field with large turbulence intensity generated by a mechanical turbulence generator in a small wind tunnel. The large turbulent Reynolds numbers, Re_L > 3000 and Re_λ > 200, were obtained in the present experiment. These values were proven to exceed the criteria allowing the wide internal subrange to exist in the energy spectra. The turbulent Reynolds numbers decreased monotonously in the streamwise direction and attained a quasi-steady state for about X/M ≥ 50. These results suggest that it is possible to simulate the fluid dynamical phenomena of the actual large-scale turbulent flow fields in the test section of a small wind tunnel. The universal constant of Kolmogorov, α, was determined from the spectral distributions. The resultant value, α ≒ 0.64, agreed closely to those obtained in the recent results of field experiments and theoretical analyses.