Study: Sound waves can help detect structural cracks

A University of Strathclyde researcher has discovered a system for using sound waves to spot potentially dangerous cracks in pipes, aircraft engines and nuclear power plants, a study report published Thursday said.

The study found that transmitting different types of sound waves can help detect structural defects more easily by varying the duration and frequency of waves.

“Welds are vitally important in ‘safety critical’ structures, like nuclear power plants, airplane engines and pipelines, where flaws can put lives at risk," Katherine Tant, a research associate with Strathclyde’s department of mathematics and statistics, who led the study, said.

Tant noted that one type of weld, made of austenitic steel, is difficult to inspect.

"We were able to devise solutions involving the use of ‘chirps’ – coded signals with multiple frequencies which vary in time," she said.

The study has been published in the journal Proceedings of the Royal Society A.

"The type of flaw identified depends on the method used," Tant said. "An analogy would be the type of echoes produced by clapping loudly in a cave -- a single clap may allow you to judge the depth of the cave, while a round of applause will give rise to a range of echoes, perhaps allowing you to locate boulders."