Hydrofoil Simulation Equations Study: Mathematical Model Report: Volume II. Equations and Methods for Simulation of Hull Lift, Drag and Pitch Moment

摘要

In anticipation of the growing use by the U. S. Navy of hydrofoils as gun boats, patrol boats, and as antisubmarine warfare craft, a study was initiated to formulate the mathematical models required for simulating the hydrofoil as a pilot-controlled training situation and as a target or own-ship vehicle. This report presents the results of the study. The mathematical formulation was developed in three parts; each part is treated as the topic of a separate volume of the report. Volume II treats hull lift, drag and moment relationships as they pertain to craft operation on a straight course in smooth water. The methods described depend on the availability of hull model data covering the full range of speed, draft, and pitch angles experienced by a hull during take-off and landing transitions. Material presented in the three volumes enables a person to assemble a hydrofoil simulation which will demonstrate craft dynamic behavior during take-off or landing in smooth water, during foilborne maneuvers in smooth water or regular waves, and during foilborne operation on a fixed heading in realistic seas. The limitations inherent in the work at present result mainly from a lack of a complete theoretical or empirical description of foil and strut hydrodynamic characteristics. For future improvements in simulation realism, advancements must be supported in the field of hydrofoil hydrodynamics.