A VORTEX MODEL OF A HELICOPTER ROTOR
Journal Title: INCAS BULLETIN - Year 2009, Vol 1, Issue 1
Abstract
A vortex model of a helicopter rotor is presented. Each blade of the rotor has three degrees of freedom: flapping, lagging and feathering. The motions after each degree of freedom are also known for all blades. The blade is modelled as a thin vortex surface. The wakes are free fluid surfaces. A system of five equations are obtained: the first one is the integral equation of the lifting surface (rotor), the next three describe the wakes motion, and the last one relates the vortex strength on the wakes and the variation of vorticity on the rotor. A numerical solution of this system is presented. To avoid the singularities that can occur due to the complexity of vortex system, a desingularized model of the vortex core was adopted. A Mathcad worksheet containing the method has been written. The original contribution of the work. The calculation method of the motion of the wakes free vortex system, the development of the vortex cores in time and a new method to approximate the aerodynamic influence of remoted wake regions
Authors and Affiliations
Valentin BUTOESCU
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