Extruding Ice as Ribbons and Rods
Dr. James R. Carter, Professor Emeritus
Illinois State University, Normal, IL 61790
|In fall 2004 I became fascinated with
ice formations that occur on
selected plant species. Since then I have been trying to learn
more about ice, in part by trying to grow ice during cold spells. Then
in January 2007 I was introduced to some beautiful photos of
ice growing as ribbons
and rods from a metal fence. By this time I had concluded I was
not going to grow ice flowers from plant stems this winter, so I focused on
growing ice ribbons and rods from inanimate objects. In winter 2007-08
I took on this task again and
came up with some
After many trips out into the yard and the garage, many notes, broken pipes and some cold fingers I achieved success. Below are two 36 inch long, 0.5 inch diameter, black steel pipes stuck in snow. I knew if the pipe were of uniform diameter ice would come out the top as a column of ice.
But, based on the photos of ice ribbons and rods on the fence, it seems that ice had been extruded from a larger cross-section area through a smaller area to take on some exotic forms. The examples here illustrate such extrusions. The pipe on the left is capped by a 45 degree angle that is only 0.64 the cross-sectional area of the long pipe. In this case ice had to move up the pipe, make the turn and extrude from a smaller orifice. The image on the right shows a ribbon of ice extruding from the flattened end of the pipe and a small rod of ice emerging from a 7/32nds inch hole drilled into the pipe. Sorry to say part of the small rod of ice broke off when the pipe was moved to put the pipe in the snow.
Above are three views of the ribbon and thin rod of ice before it was broken. In this case white cardboard is the background of the photo.
My laboratory to carry out these experiments was my yard and garage. Thankfully, I had continuously cold days to permit me try different experiments to converge on what I was looking for. My first success with growing a ribbon of ice from the flattened pipe was lost when I left the pipe outside in the sun. Although the temperature was well below freezing the solar radiation melted my ribbon.
I flattened the end of the pipe some more and grew the ribbon below. These are three views of the same ribbon. In this case I had not yet drilled a hole in the pipe.
My first success was getting a rod of ice to emerge from the angled piece atop the pipe. I tried to grow ice from large plastic tubes and got different results. But, in doing so, I gained insight into the processes of freezing of ice.
In the left image below, I filled both large plastic tubes with tap water. So that water would freeze from the top down, the base of the tubes was in contact with a heat source and the temperature was kept above freezing. I monitored temperatures with digital thermometers connected with cables to the sensor. The temperature sensor can be seen in the top of the column of ice in the left-most photo below.
In the tube at the front where there is no cap, a column of clear ice has been extruded upwards. The tube behind has a white cap with a large hole cut into the cap. In this case the water rose up and out of the hole and flowed down the side of the tube. With time ice sealed off the top of this tube and the tube shattered, as seen in the middle photo. The tube that had no cap at the top did not break.
An iron pipe 18 inches long with the angle piece was nestled between the plastic pipes. Its base was in contact with the heat source. There is a small rod of ice emerging from the angled cap, but the icicle hanging down from the end shows that water first emerged from the pipe before ice blocked the orifice. Ultimately, the iron tube ruptured at the base.
The photo on the right shows a cross-section of the tube that broke. It shows that the ice forms from the outside into the center and in this case it ruptured before all of the water froze. Of course, ice formed at the top of the tube because it too was an outside surface.
I abandoned the plastic tubes and turned to black steel pipes. Using the same angle piece I tried to grow a rod of ice similar to what I grew in the example above by keeping the temperature above freezing in the middle or lower parts of the pipe while trying to get the opening to freeze first. I got mixed results, but generally had water come out before ice sealed the opening.
Finally, to make certain I had ice at the opening, I temporarily sealed the angled and flattened openings of both pipes with plastic films and many rubber bands. Then I filled the pipes with approximately 10cm (4 inches) of water and kept the pipes vertical so that ice would form at the angled/flattened end. I used only this amount of water because that was a little more than could be extruded but would minimize the amount of ice that would have to be moved by the expansion of newer ice.
After that small length of ice was solid, I filled the both pipes with near-freezing water and sealed the pipes with metal caps. I then removed the plastic film seals at the open ends and placed the pipes in a horizontal position. Within a few hours ribbons and rods of ice emerged. This proved to be successful.
The fact that the solid ice emerged from the openings that were of smaller cross-sectional area than the pipe demonstrates that the ice was extruded, and therefore it must have gone through a plastic state. I understand plasticity exists in glacier flow but was surprised to see it in this situation.
Below are three examples of three rods of ice that were extruded from the angled piece attached to the 36 inch pipe. Each shows some unique characteristics. In one case I straightened a red paper clip and dropped it in the pipe before pouring in the 10cm of water. That red paper clip is visible on the right.
It proved quite difficult to get good photos of these ice formations in many cases. The objects are so small my digital camera focused on the background and not the object. I did not keep good enough records to know if the use of tap water or distilled water makes a difference. I need another cold spell to test this.
But, I did replicate the ice formations Sheryl found on her fence. These formations demonstrate that ice under the right pressure environment can be transformed into interesting shapes. And, check out my ice formations created in the winter of 2007-08.
Now, does the formation of ice in this case tell us anything about the ice flowers and ice ribbons that grow on selected species of plants? Stay tuned.
One of a number of pages on Ice Flowers and Ice Ribbons by Jim Carter.