Global load determination of high‑speed wave‑piercing catamarans using finite element method and linear least squares applied to sea trial strain measurements

Twin hull high-speed catamarans encounter a wide range of sea wave loads. This paper studies the full-scale prediction of global loads on a high-speed catamaran using linear regression analysis based on finite element results. Load cases based on Det Norske Veritas rules are applied to a finite element model to derive load–strain transformation. Strain responses are evaluated at 16 different locations on the catamaran finite element model corresponding to the strain gauges positioned on the HSV-2 Swift 98m Incat catamaran during sea trials. A transformation matrix is generated using the concept of ordinary least squares, to convert from strain responses to the equivalent DNV global load cases. This is applied to determine global loads during several sea trial runs in different heading angles and speeds of 10, 20 and 35 knots. These loads then are compared to show each global load severity at specific speed or heading angle.