Flow Visualization
Because air is transparent it is difficult to directly observe the air movement itself. Instead, multiple methods of both quantitative and qualitative flow visualization methods have been developed for testing in a wind tunnel.
Read more about this topic: Wind Tunnel
Famous quotes containing the word flow:
“Opinionated writing is always the most difficult ... simply because it involves retaining in the cold morning-after crystal of the printed word the burning flow of molten feeling.”
—Gavin Lyall (b. 1932)