Taylor Columns


SIO 210 Fall 2014
Mark Moosburner, Chang Sun, and Daniel Yee

Experimental Setup, Troubleshooting, and Results

Preliminary experiments were conducted in Ritter 229, access to the room after hours and weekends was achieved by borrowing a key from the TA (Madeleine Hamann). A white plastic square plate was placed on top of the turn-table to serve as a white background to help contrast the dyes used in the experiment. A long flexible clear plastic was clipped into the shape of a cylinder whose diameter matched the length of a side of the square tank for creating a cylindrical body of water. The tank was positioned over the white square plate, ensuring that the corners sat evenly above the four marked positions of the turntable. The tank was filled to 3 inches below the edge of the cylinder with tap water by connecting a rubber hose to faucet head. Then the rotating turntable-cart was position with space on all sides to reduce bumping and vibrations from adjacent objects, and power was connected for the rotating table motor and camera. Additionally, a remote controlled GoPro Hero 3 was clamped on the post alongside the turntable camera in order to record footage of the experiment. A hockey puck was used as the obstacle and was placed about 2 inches from the edge of the cylinder. The tank was allowed to reach solid body rotation for at least 20 minutes for every attempt made to generate a Taylor column.

It took several attempts to generate a Taylor column, and various combinations of solid body rotation velocity and changes in velocity we tried. To remove as many variables that could contribute to inertial forces, the windows were closed and the vibrating power supply was removed from the tank experiment table. The experiment was attempted at the fastest speed, but that of course introduced too much inertial forces and the dye could be seen feeling the effects of centrifugal force. To save time between attempts, bleach was added to bleach the dye color.

In end, the optimized condition used for successfully generating a Taylor column in this experiment was starting with a rotational speed reading of 44 on the bike odometer, which was calculated to be about 4.4 rpm. After 20 minutes of rotation, the water was assumed to be in solid body rotation. Then, dye droplets were added behind the puck. The turntable was then carefully slowed to a speed of 42 or 4.2 rpm; this required some skill as the knob is quite sensitive. This action quickly slows down the speed of the tank and the puck, while inertia of water wants to maintain the same speed. This moves water across the X-Y plane of the puck and a Taylor column is generated and visualized by the dye.


Real Life Example


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As a potential example of a real world Taylor column, the Chukchi Sea located north of the Bering Strait, and between Alaska and Siberia, is home to the Herald and Hanna Shoals. During the Summer, warmer waters flow in through the Bering Strait and encounter the sea ice, which begins to melt. However, there is an area over the sea in which ice does not melt away, and this ice sits above the Herald and Hanna Shoals. It is hypothesized that this could be due Taylor columns forming above the two shoals, which insulates the ice at the surface from the warmer waters (Martin, Seeke, and Drucker 1997).

Below is a video of one o the successful runs achieved by conditions described in the methods section:



References:

Martin, Seelye, and Robert Drucker. "The effect of possible Taylor columns on the summer ice retreat in the Chukchi Sea." Journal of Geophysical Research: Oceans (1978–2012) 102.C5 (1997): 10473-10482.


Outside Links: Lab Guide
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