Hydrodynamic Performance of the Large Cavitation Channel (LCC)

The U. S. Navy William B. Morgan Large Cavitation Channel (LCC) in Memphis, Tennessee, is the world's largest water tunnel. This report is a comprehensive documentation of its hydrodynamic performance. Three key characteristics of tunnel velocity were measured: temporal stability, spatial uniformity, and turbulence. Temporal stability and spatial uniformity were measured by laser Doppler anemometer (LDA), while the turbulence was measured with a conical hot-film and constant temperature anemomometer (CTA). The velocity stability at a single point for run times greater than 2 hours was measured as 0.15 % at the 95 confidence level for velocities from 0.5 to 18 m/s. The spatial non-uniformity for the axial velocity component was +/-0.34 to +/-0.60% for velocities from 3 to 16 m/s. The non-uniformity in the vertical velocity was nominally 2%. The turbulence or relative turbulence intensity, which is the commonly reported performance characteristic for water tunnels, was measured as 0.2 to 0.5% depending on tunnel velocity. Additional information includes calibration of the LDA and CTA, test section velocity as a function of pump speed, acceleration of the test section velocity, velocity spectra, and color contour plots of the axial and vertical components for velocity uniformity. The measurements demonstrate that the LCC is a high-quality world-class water tunnel. The original document contains color images. All DTIC reproductions will be in black and white.