Aerodynamic Characteristics of Sails in Cascade

Abstract

A method is presented for the numerical analysis of the aerodynamic characteristics of sails in a cascade when all sails take the same shape. In this analysis, the authors apply a series of Chebyshev polynomials to express the pressure distribution and chordwise shape. It is found that the aerodynamic stability of a sail decreases with increasing stagger angle from the viewpoint of the values of maximum tension eigenvalues, but it increases when we judge it in terms of the critical excess length ratio. The effects of stagger angle on the values of the lift coefficient and the position of the center of pressure are shown in diagrams as functions of an angle of attack, solidity and excess length of membrane over the chord length.