Modeling of the wind generated force acting on the liferaft

The aim of this paper is to derive a mathematical model for estimating the wind forces and wind moments effects a life raft. The mathematical model based on data from laboratory experiments. Forces due to the action of wind are adequately described. The governing physical equations, however, contain characteristics of the environment that are often not well quantified. In the strong wind condition, when the wind speed is much larger than the current and body speeds, all wind-generated forces must be taken into account. Friction and pressure forces exerted by the wind on the upper part of the floating body result in the wind force, which has a downwind component (drag) and a crosswind component (side force or lift), [1][2]. The drag component is always positive. The side force or lift component can be positive or negative[8]. The lift depends on the wind speed, body geometry, and strongly on the angle between the long axis of the floating body and the wind direction. In this paper the author presents models of wind forces acting at a life raft. Data from laboratory experiments (wind tunnel [5]) are used to build dynamical models.