Propeller Blade Cross-Sections

Introduction

Due to the unique way that the Prop component operates, there are some specifics to cross-section control that need to be addressed.  For many cross-section types such as airfoils, the Chord, Thick, and CLi curves are going to control the overall shape of the section.  However, for traditionally body-type sections such as ellipses, rectangles, and General Fuse, the height and width are controlled by the Chord and Thick curves while CLi has no effect as there is no analogous parameter.  Custom airfoil files are affected differently.  The thickness of the custom airfoil (or other custom section file) will be automatically set by the Thick curve but the camber of the section will remain unaffected.  If you wish to have a custom airfoil file retain the proper thickness, you may either input the proper value to the Thick curve at the given blade station or if you are unsure of the value, the Base T/C is calculated for each AF_File under the XSec tab.

The location along the blade (Radius) of cross-section 0 (root) defines the innermost station for the propeller, not the r_0 parameter under the Design tab which is actually the lower limit of activity factor integration.  The radius of XSec_0 may be set anywhere between 0.0 and the location of the following section.  Similarly, the radius of any Prop cross-section may be set between the radial location of the prior and following cross-sections.  The final cross-section radius is always set to 1.0.