Spotters needed for solitary waves on the canals
MEMBERS of the public are being asked to look out for, record and report sightings of solitary waves on the canals.
Dr Momchil Terziev, a postdoctoral researcher at the University of Strathclyde, has been awarded Royal Society of Edinburgh award funding for research into solitary waves. The aim of the project is to discover where solitary waves occur today and document them on a map.
Solitary waves (also called solitons) are a special type of wave that are perpendicular (at 90 degrees to the water surface) and span the entire width of a canal. They are likely to be seen ahead of a boat because their speed is slightly higher than the boat that generates them. They are generally a few inches in height and consist of a single crest without an accompanying trough. They could be seen a long distance in front of an advancing boat.
Dr Terziev says that he is running the project to see if solitary waves still occur on Scotland’s canals. Mathematical equations say that it is quite difficult for a vessel to reach the speed needed to create a solitary wave and requires a lot of power, probably more than a typical boat can produce. It could be that relatively short sections of the canal may be silted up or restricted due to a bridge and when a boat passes through such a restriction, it might enter the range where solitary waves are produced.
Since very restricted waters are needed for this to happen, the presence of solitary waves could be a reliable indicator of excessive restriction in the canal. Dr Terziev is keen for anyone on the canals to keep a lookout for these waves to help prove whether or not they actually occur.
Members of LUCS have reported that they do occasionally notice a fore-aft movement of lightly moored boats, even when no boats nearby are moving. When Dr Terziev visited LUCS, he saw a single wave spanning the entire width of the canal, an indication that one of LUCS’ boats was returning from a trip. The question is do these waves occur elsewhere and, if so, how often?
These waves are a unique piece of Scotland’s canal heritage. In 1834 the engineer John Scott Russell observed a solitary wave in the shallow water of the Union Canal. Scott Russell was a Scottish engineer, naval architect, shipbuilder and scientist. He was experimenting on the Union Canal to design an efficient canal boat hull and watching the motion of a boat which was being rapidly towed along the canal.
The boat stopped suddenly, causing a solitary wave to move rapidly along the channel without changing its form or losing speed. Scott Russell’s work on solitary waves was rediscovered in the 1960s and the theory is now employed in a wide range of disciplines, including fibre optics used to transmit digital signals over long distances.
John Scott Russell gives his name to the Scott Russell Aqueduct, built in 1987 to take the canal over the A720 Edinburgh city bypass, a leap of faith as it was ahead of the Millennium funding to restore the entire canal. In 1995, scientists at a conference at Heriot-Watt University successfully recreated a solitary wave on the Scott Russell Aqueduct.
Readers interested in the project, or who want to get involved, can find out more by contacting Dr Terziev – who is also working south of the border with IWA – via scottish-solitarywaves.github.io/