Tests of Spheres with Reference to Reynolds Number, Turbulence, and Surface Roughness
This is a 1935 NASA technical report, drawn from NASA Technical Reports Server records, presenting wind-tunnel tests of spheres to study how Reynolds number, air turbulence and surface roughness change drag and pressure. Its engineering plots of drag coefficient against Reynolds number and pressure curves against dynamic pressure are plain black-and-white line graphs on grid paper, with sketches of a sphere mounted on struts and wires. A designer might take from them the clean graphing style, dotted data markers, and the sphere-and-support diagrams as simple technical schematics.
