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The rotating table was spun up to 0.1 

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body rad s^{-1}

 and allowed to spin until a paper dot placed on the surface of the water appeared motionless to the overhead corotating camera, which was physically attached to the rotating table. The canister was filled with ice until full and then topped up with water.

The surface speed of the water was measured by tracking black paper dots in the Particle Tracker application. The speed on the tank floor was measured by tracking the purple pigment trails from granules of potassium permanganate using timecoded screenshots in the Particle Tracker.  Water speed shear between the top and bottom of the tank was measured with drops of blue food dye. 

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A metal canister of radius 18 

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 was placed in the center of a tank of radius 31

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. Again six HOBO temperature sensors were taped to the tank in the arrangement shown in the figure below. This arrangement differs from the first experiment: thermometers 1 through 5 were placed in a line radially from the tank center; thermometer 6 was placed between 3 and 4, on the bottom of the tank but 10

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 further in the clockwise direction. This arrangement was devised to capture thermal signatures of the eddies that were hypothesized to form. Thermometer 1 was placed at a height of 11 

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 and thermometer 5 at a height of 9 

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. The tank was filled with still water to a height of 14

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 with water .

The rotating table was spun up to 1 

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body rad s^{-1}

 and allowed to spin until a paper dot placed on the surface of the water appeared motionless to the overhead corotating camera. In this setup, the speed of the corotating camera was synced electronically with the table rotation speed through a computer interface. The canister was filled with 521.6

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 of ice and then topped up with water.

Surface speed, bottom speed and shear were measured as in the previous experiment: paper dots, permanganate granules and food dye, respectively. Two colors of food dye were used to illustrate eddy formation: blue dropped in the colder water near the canister and red in the warmer water near the outside edge.  

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Slow Rotation Experiment

Fast Rotation Experiment

Bibliography