Figure 3
From: Bubble cascade in Guinness beer is caused by gravity current instability
(a) A snapshot of the bubble-concentration texture of Guinness beer in the pint glass. The corresponding movie is presented in the Supplementary Movie S1. (b), Temporally expanded image of the bubble-concentration distribution at the white dotted vertical line in Fig. 3a (near the centreline of the pint glass). (c) Enlargement of (b) showing travelling waves in the downward direction. The slope of the triangle shown at the upper right corresponds to reference value of −35 mm/s for the maximum downward velocity of the wave5.
