Hills and other topology can have interesting and complex effects on a flowfield. With the FAITH experiment, NASA has been investigating an axisymmetric model hill using a combination of experimental methods. The video above shows flow visualization over the hill in a water channel using dye injection both upstream and downstream of the model. They’ve also done wind tunnel tests with oil-flow visualization, particle-image velocimetry, pressure sensitive paint and other measurement techniques. There are nice photos of some of these by Rob Bulmahn. By combining qualitative and quantitative flow measurement techniques, the researchers are able to capture many different aspects of the flow, which can then be shared and compared with other groups’ works. (Video credit: NASA Ames Research Center)
Tag: water channel

Shuttlecock Flow Viz
The flow around a shuttlecock is visualized in a water channel using fluorescent dye illuminated by laser light ultraviolet LEDs. Note the recirculation zone on the upper shoulder. Experimenters can match flow characteristics in water to that in air by matching the Reynolds numbers. (Photo credit: Rob Bulmahn)
Updated, thanks to information from the photographer. Thanks!

