Experimental study on ice breaking by flexural-gravity waves induced by a moving submerged spheroid

Artikel i vetenskaplig tidskrift, 2026

A prolate spheroid model is towed beneath an ice sheet in outdoor ice-tank experiments to study the effects of a moving pressure source, which can induce flexural-gravity waves in an ice sheet. To replace the previous cable-driven system, a new underwater towing setup is developed, constraining both the spheroid's horizontal and vertical motions. For the first time, the hydrodynamic forces acting on the body beneath the ice sheet can be directly measured using this setup. Results demonstrate that the spheroid velocity, submergence depth, and ice thickness jointly govern the maximum ice deflection, damage severity, and the drag and lift characteristics of the spheroid. The drag and lift coefficients vary non-monotonically with the velocity, exhibiting distinct differences from the spheroid moving beneath a free surface or a rigid wall. A new dimensionless parameter is proposed to improve the existing ice failure criteria. This new criterion is based on measured ice deflection and a characteristic length scale of the ice sheet, providing a practical and robust parameter for wave-induced ice failure.