VORTEX THEORY OF AN AIRSCREW IN CONSIDERATION OF CONTRACTION OR EXPANSION OF SLIPSTREAM AND VARIATION OF PITCH OF VORTEX SHEETS IN IT

Abstract

The airscrew theory in consideration of the contraction or expansion of its slipstream and the variation of the pitch of its vortex sheets in the slipstream is derived. The calculation charts, which are necessary for the application of this theory to practical calculation of the performance of an airscrew, are provided. The method of application of this theory to practical case is described precisely. The present theory is applied to the calculation of a four-bladed windmill and discussions are made about the results of the calculation. Some informations of the structure of the tangential component of induced velocity are given