Accession Number : AD1013408

Title :   Designing Small Propellers for Optimum Efficiency and Low Noise Footprint

Descriptive Note : Conference Paper

Corporate Author : U.S. Air Force Academy Air Force Academy United States

Personal Author(s) : Wisniewski,Charles F ; Byerley,Aaron R ; Heiser,William H ; Van Treuren,Kenneth W ; Liller,William III R

Full Text :

Report Date : 26 Jun 2015

Pagination or Media Count : 17

Abstract : A topic of increasing importance in the Unmanned Aerial System (UAS) community is the design and performance of open propellers used in hand launched, small UASs. The design and testing of these propellers is necessary to accurately predict UAS operation. This paper describes the design methodology used by Baylor University and the USAF Academy to design propeller blades for optimum efficiency and low noise. Propeller blade design theories are discussed as well as an overview of several of the existing design codes. Included is a discussion on geometric angle of attack, the induced angle of attack, and their impact on propeller design. The design program BEARCONTROL was developed which incorporates the programs QMIL and QPROI). Supplemental codes were also developed to work with Bearcontrol to design a propeller with a constant chord and variable twist. This resulted in the angle of attack for L/Dmax being used from the propeller hub to the tip. BEARCONTROL is a program written in MATLAB that gives a user the ability to quickly design a propeller, predict its performance, and then create a 30 model in SolidWorks. The MATLAB GUl ultimately results in a mostly automated process that is simple to use for individuals who are unfamiliar with command prompt programs and SolidWorks modeling. Also incorporated into BEARCONTROL is the program NREL AirFoil Noise (NAFNOISE) developed by the National Renewable Energy Laboratory (NREL). This program predicts the noise of any airfoil shape and provides a comparison for optimizing/minimizing predicted noise for the propeller being designed. Construction methods and materials also have a direct impact on cost, durability and operability when using a rapid prototype process to fabricate propellers. An overview of materials and construction methods used in this research are discussed. Incorporation of a hub with interchangeable blades is also presented as a more efficient testing method.

Descriptors :   propeller blades , propeller noise , DRONES , test methods

Distribution Statement : APPROVED FOR PUBLIC RELEASE