Data for "Schlieren and BOS velocimetry of a round turbulent helium jet in air"

This is a subset of data used in our publication Schlieren and BOS velocimetry of a round turbulent helium jet in air 

In the four helium-jet schlieren-image datasets given below, the nozzle diameter is 1.4 mm, the camera frame rate is 6000 fps and the individual image exposure is 0.0001667 s. 3000 images are provided for each dataset, or 1/2 s in real-time, which we determined to provide statistically-adequate data. Please see the paper for more detail.

20210125-Run1: traditional mirror-schlieren, $Re_d = 5,890$, $U_j = 436$ m/s, and the scale is 0.29 mm/pixel.

20210206-Run1: traditional mirror-schlieren, $Re_d = 11,300$, $U_j = 682$ m/s, and the scale is 0.29 mm/pixel.

20210419-Run1: background-oriented schlieren (BOS), $Re_d = 5,890$, $U_j = 436$ m/s, and the scale is 0.26 mm/pixel. These are raw BOS images that must be processed with a reference image in order to yield pseudo-schlieren results. The reference (flow-off, tare) image is the first image in the sequence and is so named.

20210420-Run1: background-oriented schlieren (BOS), $Re_d = 11,300$, $U_j = 682$ m/s, and the scale is 0.26 mm/pixel. These are raw BOS images that must be processed with a reference image in order to yield pseudo-schlieren results. The reference (flow-off, tare) image is the first image in the sequence and is so named.