Investigation of front hydrofoil position influence on the hydrofoil-assisted craft

The hydrofoil is utilized to generate lift force and craft center of gravity (CoG) rise-up, resulting in reduced total resistance and improved performance of hydrofoil-assisted craft. This study focuses on the performance of a hydrofoil-assisted craft equipped with a double front foil and a single rear foil. The position of the front hydrofoil is adjusted by shifting it back and ahead by one chord length in the longitudinal direction to investigate the craft's performance. Various parameters including hydrodynamic resistance, trim angle, CoG rise-up, and hydrofoil pressure coefficient are examined at different volume Froude numbers (Fn∇). The results indicate that the total resistance coefficient exhibits similar behavior across all three states within the Fn∇ range of 0.73–2.2. However, when the Fn∇ is increased to 2.93 and the front hydrofoil is shifted one chord length ahead, a significant increase of 27% in CoG rise-up and 18% in trim angle is observed compared to the base case study. Likewise, a back shift of the front hydrofoil leads to a 54% increase in CoG rise-up and a 30% increase in trim angle. •Hydrofoil craft performance with a double foil at the front and a single foil at the rear were analyzed experimentally and numerically.•Three front hydrofoil position were proposed in the longitudinal direction to investigate the hydrofoil craft performance.•Hydrodynamic resistance, trim angle, the center of gravity rise up and hydrofoil pressure coefficient were presented and discussed under different Froude number.