چکیده
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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 in order
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 the other word, can be considered as basics of a final 6DOF model. Current paper address
hydrodynamic modeling of yawed motion for hard-chine planing boats in calm water.
The current research paper is primarily focused on determination of horizontal force and yaw moment acting on
the boat as is moves forward in steady yawed condition. The derivation approach is based on mathematical
formulation of 2D T 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 of Brown
and Klosienki (1994a, b) and Morabito (2015). 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 Moabito (2015) 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 moment are in a fair
agreement with previous experimental data.
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