Item 1122
OTHER:
Aerodynamics - Rotor Disk - Dual Configuration - Intermeshing
Overview:
Intermeshing Craft:
Inside Concepts:
Pros & Cons:
Outside Helicopters and Outside Concepts:
Outside Technical Reports:
Disk Area:
Calculation used for obtaining the area of overlap: Angle is in Radians.
A = 1/2 (R2
(θ - sinθ)) = 1/2 (10 * 10 (2.878 - sin(2.878))) = 1/2 (100 (2.8784 - 0.261)) = 1/2 (100 *2.617) = 130.9
|
|
Individual Twin Disk: |
Combined Twin Disks: |
Single Disk: |
|
Radius: |
10 |
~ |
14.14 |
|
Area: |
314.3 |
628.6 |
628.6 |
|
Area of Overlap (Circular Segment): |
130.9 |
261.8 |
~ |
|
Area Excluding Overlap: |
183.4 |
366.8 |
366.8 |
|
Radius based on Area of Twin Disks with Overlaps Excluded: |
~ |
~ |
10.8 |
|
Total Lateral Span: |
~ |
22.63 |
21.6 |
|
Total Longitudinal Span: |
~ |
20.0 |
21.6 |
The above data and the comments below only consider the main rotors. They do not include the 10-12% tail-rotor power consumption, nor do they include the downwash velocity on the fuselage, which is dependent on its location under the disk(s).
The area of the circular segment is 41.6% of the disk's total area. This would suggest that the power should be considered as; 2 * (17% * isolated rotor power + 83% * co-located rotor power). Using the figures from OTHER: Aerodynamic - Rotor Disk - Dual Configurations, 17% * 65 hp + 83% * 100 hp = 94 hp. In other words to provide a specific thrust will require 65 hp form the side-by-side configuration, 77 hp from the Interleaving configuration, 94 hp from the Intermeshing configuration, and 100 hp from the coaxial configuration.
Induced Power:
xxx
(κint)
copied over
Intermeshing (Synchropter):The required power is increased by a factor (K) = 1.46 - (0.253 * (Stagger / R))
Dual Rotor Configurations:
Coaxial | Intermeshing | Interleaving | Side-by-Side | Tandem
Introduction Page | SynchroLite Home Page | Electrotor Home Page | UniCopter Home Page | Nemesis Home Page | AeroVantage Home Page
Last Revised: July 6, 2011