Underwater sound waves might weaken tsunamis by redistributing their power earlier than they strike coastlines, saving lives and infrastructure in at-risk areas throughout the globe, in line with new analysis.
The examine, led by Cardiff College, reveals how ocean waves and sound waves, beforehand thought unrelated, can work together to reshape their dynamics.
The interplay, which requires two acoustic waves and a single floor gravity wave, could be matched just like the rhythm of a track to a dance, to shift power between the waves, the researchers declare.
This course of, introduced within the Journal of Fluid Mechanicsmight assist handle challenges in tsunami mitigation and marine renewables by defusing harmful waves or amplifying ocean waves to harness their energy for clear power.
Lead writer Dr Usama Kadri, Reader in Utilized Arithmetic at Cardiff College, stated: “Our study describes how these two wave types, which exist in parallel worlds, can nevertheless exchange energy when the right conditions mature.”
This ‘conversation’ between acoustic waves and floor gravity waves is made doable by a singular three-wave interplay referred to as triad resonance. In concept, this course of permits us to successfully management wave power – both by decreasing damaging waves like tsunamis or boosting ocean waves for renewable power seize.
“This is important because it offers us a physics-based way to reduce tsunami energy, weakening them significantly, which is not possible with current methods like seawalls or warning centres.”
The examine builds on Dr Kadri’s earlier analysis on tsunami mitigation, together with work on the 2022 Tonga tsunami, the place he found pure acoustic-gravity interactions affect wave behaviour at an oceanic scale.
Right here he identifies sensible tuning parameters together with wave frequency, amplitude and depth to optimise power redistribution for real-world purposes.
‘Sweet spot’
Dr Kadri added: “One other element is that shallow water dramatically boosts power switch, aligning with the place tsunamis develop into most damaging.
“This natural ‘sweet spot’ could simplify practical applications.”
Along with tsunami mitigation, the group hope their findings may help handle the present limitations within the marine renewables sector, the place present applied sciences battle to effectively seize power from ocean waves, particularly in deep water.
Through the use of acoustic-gravity interactions to amplify floor waves, renewable power harvesting may very well be more practical, in line with the group.
They’re now working in direction of offering a proof of idea for his or her concept in a laboratory setting, as a part of a Leverhulme-funded mission.
“Once lab validation is achieved, designing real-world scaled acoustic generators becomes an engineering challenge ‘only’,” says Dr Kadri.
“Though further study will of course be required to ensure no harm is made to marine life as part of the process.”
The paper, ‘Resonant triad interactions of two acoustic modes and a gravity wave’, is printed within the Journal of Fluid Mechanics.
