Each month in “Slice of History” we’ll be featuring a historical photo from the JPL Archives. See more historical photos and explore the JPL Archives at https://beacon.jpl.nasa.gov/.
This test setup was part of an investigation in 1954 of the stability of laminar pipe flow with respect to disturbances of different frequencies and amplitudes. A disturbance generator was developed using vibrating aluminum reeds and instruments measured how a small amplitude disturbance in the air flow changed as it propagated down the 115–foot length of a 2” aluminum pipe. It appears to be located in the concrete channel that was used in the 1940s as a hydrodynamic tank with a rocket-propelled towing car (the “Hydrobomb”). At the end of the room you can see metal rungs that were used to climb down into the channel when the water was drained.