Aerodynamics


Aerodynamics of Rotary Wing and Propellers

Below is a list of links to various documents and web-resources related to aerodynamics of a rotor/propeller.   

 # Paper/ software Document  Description Notes
 1 PRotaryWing Aircraft; MECH5740 Lecture Notes; Prepared by: Osvaldo M. Querin; SCHOOLOF MECHANICAL ENGINEERING, University of Leeds.PDF file Lecture notes covering in detail all aspects of the rotary wing aerodynamics and design.  This is an extremely useful tutorial.
 2 PFlight dynamics-I; Course of lectures by Prof. E.G.Tulapurkara, Indian Institute of Technology, Madras

Chapter 4, Lecture 14
Chapter 4, Lecture 15
  • Parameters for describing propeller performance and typical propeller characteristics
  • Selection of propeller diameter for chosen application
  • Procedure for obtaining propeller efficiency for given h,V, BHP and N
  • Variations of THP and BSFC with flight velocity and altitude
  • Loss of propeller efficiency at high speeds

 This is an extremely useful tutorial.
 3

 PModel Airplane Propellers by  W. B. Garner; March 2009; 
PDF File
 This document describes the general characteristics of model airplane propellers and their application.  
 4 PPropeller Performance Data at Low Reynolds Numbers by John B. Brandt. and Michael S. Selig; University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA

PDF File
 While much research has been carried out on propellers for full-scale aircraft, not much data exists on propellers applicable to the ever growing number of UAVs.
Many of these UAVs use propellers that must operate in the low Reynolds number range of 50,000 to 100,000 based on the propeller chord at the 75% propeller-blade station. Tests were performed at the University of Illinois at Urbana-Champaign
(UIUC) to quantify the propeller efficiency at these conditions. In total, 79 propellers were tested and the majority fit in the 9- to 11-in diameter range. During the tests, the propeller speed (RPM) was fixed while changing the wind-tunnel speed to sweep over a range of advance ratios until reaching the windmill state (zero thrust). To examine Reynolds number effects, typically four RPM’s were tested in the range 1,500 to 7,500 RPM depending on the propeller diameter. Propeller efficiencies varied greatly from a peak near 0.65 (for an efficient propeller) to near 0.28 (for an exceptionally poor propeller). Thus, these results indicate that proper propeller selection for UAVs can have a dramatic effect on aircraft performance.
 
 5 P Propeller efficiency articles by David F. Rogers.

LINK
 Three articles discussing a subject of the propeller efficiency under different conditions including take-off (LINK) 
 6 SW Aerodynamics of Model Aircraft Webpage maintained by Martin Happerle.

 Lots of useful information including JavaProp and JavaFoil  software.
 7 P Static Testing of Micro Propellers by Robert W. Deters and Michael S. Selig, University of Illinois; 26th AIAA Applied Aerodynamics Conference, 18 - 21 August 2008, Honolulu, Hawaii

PDF File
 Available performance data for micro propellers are very lacking. Prediction of micro propeller performance is made difficult due to the small Reynolds numbers (less than 50,000) at which the propellers operate. A test rig was designed and built at the University of Illinois at Urbana-Champaign in order to measure the static performance of micro propellers. A load cell and torque transducer measure the thrust and torque, respectively, created by a propeller. These results are then used to find the static thrust and power coefficients. Eighteen two-bladed propellers from different manufacturers and two threebladed propellers were tested with diameters ranging from 2.25 in. to 5 in. The hovering capabilities of the propellers were also analyzed. 

Aerodynamic (Other)

Below is a list of links to books, documents and web-resources related to various aspects of aerodynamic other than rotary wing and propellers.   

 # Paper/ software Document  Description Notes
 1 P

Hoerner, Dr. Sighard F., Fluid-Dynamic Drag, Hoerner Fluid Dynamics, Bricktown New Jersey, 1965.

LINK

Hoerner, Dr. Sighard F. and Borst, Henry V., Fluid-Dynamic Lift, Hoerner Fluid Dynamics, Bricktown New Jersey, 1975.

LINK
In 1945 and 1946, Dr. Hoerner prepared a manuscript for the book Aerodynamic Drag. The technical publishing houses in New York City were not confident enough to bring a book as specialized as this to the market. As a result, he published the book himself in 1951, using a photo-offset process and sold copies of the book by mail order from his home. The book got very good reviews and demand was steady. In 1958 it was reissued as Fluid-Dynamic Drag. With the rapid progress in aerodynamics over the years, he prepared an update to the book, which was published in 1965. As before, the book was self-published by Hoerner Fluid Dynamics. This book contains documentation of the worldwide knowledge (at the time) of the sources of aerodynamic drag and the means to quantify aerodynamic drag. While substantial knowledge on this subject has been learned since 1965, this book is often the starting point in work where aerodynamic drag must be calculated.

The US Navy Office of Naval Research gave Dr. Hoerner a contract in the mid-1960s to write a companion volume Fluid-Dynamic Lift. Co-authored with Henry V. "Hank" Borst, this book was published by Hoerner Fluid Dynamics in 1975. Unfortunately, Dr. Hoerner died shortly before publication. This book, like its companion, contains documentation of the worldwide knowledge on the generation of aerodynamic lift and is still used heavily.
Very useful
 2 PProf. Bento S. de Mattos,  "Weight Estimation Using Class II Drag Calculation Method", PRJ-22 Aerospace Design, 2009

LINK
  Useful and concise overview of various drags and methods of calculation 

Subpages (2): Aerofoils Total Drag
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