Research of work of the rotting screw on the basis unsteady theory of a lifting surface

Abstract

A numerical model marine propeller at oblique flow, as based on unsteady lifting surface to applied Vortex Lattice Method (VLM) are discussed. The propeller’s blades vortices and free trailing vortex sheet was replaced on vortex loops. Because the propeller’s blades an oblique flow moves unsteady, then result thrust, torque and lateral force are varying in angle of rotation of the propeller. Lateral force has same direction as the lateral velocity component. In order to calculate, estimate degree of influence on thrust, torque and lateral force propeller at oblique flow. According to the proposed mathematical model (MM), has been studied numerically acting oblique flow at various angles flow. There is a noticeable increase propeller thrust coefficient and lateral force coefficient with increasing bevel angle, however, the change propeller torque coefficient is insignificant. The results calculation hydrodynamic forces for different angels flow at every instantaneous time are compared with works others authors. A mathematical model of a propeller operating in oblique flow, based on an unsteady lifting surface, allows one to estimate the magnitude of the variables per revolution of forces acting both on the propeller blade and on the screw as a whole. This MM can be used as a tool to study the hydrody-namics of propellers operating in oblique flow.