Turbulence Factors of NACA Wind Tunnels as Determined by Sphere Tests
A 1937 NACA technical report by the National Advisory Committee for Aeronautics, issued for aeronautical engineers and researchers, measuring airflow turbulence in wind tunnels by testing spheres. Its pictures are black-and-white photographs of test spheres, a towing rig on an autogiro, a tunnel test setup, and a line graph of Reynolds numbers, suggesting plain documentary views of research equipment that a designer could use for mid-century technical or laboratory imagery.
