Determination of forces acting on planing hulls in maneuvering has been turned into an
interesting problem during the last decade. Different methods, based on mathematical
or empirical approaches, are elicited to compute hydrodynamic forces and moments
acting on the boat in different simplified conditions, such as steady yawed or heeled
conditions.Modeling of different conditions and combining them with each other may
lead to initiate a final simulation model for 6DOF motion of planing boats in calm water.
These simple modeling approaches, in other words, can be considered as basics of
a final 6DOF model. The current article address hydrodynamic modeling of yawed
motion for hard-chine planing boats in calm water. The current research paper is
primarily focused on the determination of horizontal force and yaw moment acting on
the boat as it moves forward in a steady yawed condition. The derivation approach is
based on mathematical formulation of 2D1T theory and added mass variation in
longitudinal direction. Virtual mass of a wedge in horizontal direction is analytically
found and then the final force and moments are computed using extension of sectional
forces, acted on wedge section of the boat, over entire wetted length of the vessel.
The precision of the proposed model is verified by comparing the computational
values against previous experimental data. An improvement for the model has been
considered to conquer some of the drawbacks reported by previous researchers.
The comparison exhibits an improvement of the model; the increase in added mass
which was previously discussed by previous researchers can be seen. Also, it is
observed that in the case that the wetted length of the boat is small, the transom
reduction works well and leads to an accurate prediction of sway force. Finally, it is
viewed that the computed yaw moments are in a fair agreement with previous
experimental data.
