In this paper, a mathematical model for performance prediction of a high-speed planing hull in forward acceleration
motion has been developed. Three degrees of freedom have been considered for solving the problem.
Utilizing previous empirical equations of displacement ships, motion of the vessel in displacement regime has
been simulated. In order to model pre-planing and planing regimes, 2D T theory has been used. Equations
for prediction of performance of a surface piercing propeller (SPP) and an engine have been presented. Validity
of the proposed method has been assessed by comparing its results against previous experimental data, and
good agreement between experimental and mathematical results in prediction of performance of planing hulls
has been seen. Motion of the vessel has been simulated under the action of a semi-submersible propeller and an
outboard engine. Behavior of the vessel has been analyzed and the relationships between forces and moments
with displacements, as well as pitch and heave rate have been described. It has shown how hydrodynamic force
contributes as the beam Froude Number goes beyond 1.0, which results in increment of vertical position of the
vessel. Also, it has been observed that, net pitching moment decreases from a positive value to a negative value
in displacement regime, and then, by the appearance of hydrodynamic moment, net moment approaches zero
and finally vanishes. The results also have indicated that a sudden jump occurs in thrust force vs. time curve,
which is caused at critical advanced ratio. Beside this, it has been seen that, when propeller comes of water,
a sharp increase in advanced ratio happens. Effects of surge motion have also been studied, which show that,
maximum trim angle occurs at a larger beam Froude Number. It has also been observed that sinkage is larger
in the presence of surge motion in pre-planing regime as extra hydrodynamic forces due to damping and added
mass contributions in vertical direction occur.
