• Dr. Dominic J. Piro
  • University of Michigan
  • 1060 Torgersen Hall
  • 5:00 p.m.
  • Faculty Host: Dr. Wayne Neu

Both military and commercial ships experience harsh conditions at sea. Military vessels have experienced failures in the form of both buckling of decks and superstructure as well as fatigue damage. Impact loading, especially in the bow and on flat sterns, adds significant loading and introduces a ringing response in the vessel that reduces the fatigue life as well as causes immediate damage. As cargo vessels become larger, fluid-structure coupling becomes more important to consider in the design stage.

Current fluid-structure interaction technology in the marine industry is limited. Common hydroelastic analysis is performed with potential flow models coupled with structural solvers. These methods are fast, but do not account for wave-breaking or directly solve the three-dimensional slamming problem. Improved fluid modeling is possible with Computational Fluid Dynamics (CFD), however due to the expense of these methods the full coupled problem is not solved in practice. Therefore, an accurate and efficient fluid-structure interaction solver has been developed to analyze marine hydroelastic problems using CFD and a modal structure. Emphasis has been placed on accuracy, stability, and computational efficiency of the new method.

The current fluid-structure interaction solver has been used to analyze several problems. First a two-dimensional wedge section is studied to understand the sectional loading on a ship. The problem of constant-velocity elastic wedge impact has been used to validate the fluid-structure coupling. The new problem of the entry and exit of two-dimensional elastic wedge sections is then studied with solver. Moving to three dimensions, elastic ship problems are studied. The response of an elastic box-barge in oblique seas is used to validate the combined rigid-body and structural motions against experimental data. The JHSS segmented model tests performed at NSWCCD are used to validate the prediction of whipping response.