Uni-UAV_Propeller

UniCopter-UAV ~ Propeller
Overview: To increase the forward speed without causing an; excessive nose down pitch. excessively high loading on the absolutely rigid rotors. excessively high rotor to rotor induced vibration.

Notes:

Tractor

Tip speed maximum of 760ft/sec. for optimum efficiency. Should be run around 550 ft/sec for lowest noise.

A tip speed of 600 fps would be the most acoustically desirable, but I think that this is for a shrouded propeller.

Propeller; 30" diameter; 7.857' circumference; 4,582 rpm. What pitch?

For more information see; DESIGN: UniCopter ~ Pusher Prop - General - Pusher Prop Assist

30" dia

Consider reducing the diameter and adding a blade or two since this will decrease the vertical distance between the rotor disks and the fuselage plus power-train etc.

Initially, how about some timed out rotor blades from a large helicopter. The will have a low aspect ratio, be stiff, and have no taper, which is good.

Bolly Props Design information on this computer in file Propeller-Bolly.pdf . More on Bolly props. It appears that the make a 30-15 propeller. It mentions "Avoid using tip speeds in excess of 400 MPH if noise is of concern, although 450 MPH tip speed is common in areas of low noise sensitivity."

Tennessee Propellers Inc. May not go small enough. What is a Blower Prop?

H. Fuchs Carbon Fiber Propellers

Warp Drive Propellers Has calculator. 30" diameter at 5,800 rpm give a tip speed of 518 mph (0.67 M). It should turn a little faster.

ULTRALIGHT ARROW PROP 30" 05-31330 $127.95 Do not know what the pitch is.

Arrowprop

None of the above looking good yet.

Menz Propellers It looks like they make a 2-blade and a 3-blade, in 30/14 and 28/16

Mejzlik

Consider the propeller for the Plettenberg Predator-37

A 3-blade should result in a small diameter disk and streamtube. This will reduce aerodynamic interaction between the prop and rotors. It should also result in a higher propeller induced velocity.

Program; props18.exe

The prop diameter is 30"
The prop pitch is 18"
Engine cruise rpm is 5800
Propeller rpm is 5800
Prop efficiency is 90% (I am assuming forward propulsion assistance from rotor)
At 100% efficiency, the cruise speed is 100 mph.
At 90% efficiency, the cruise speed is 90 mph.
The tip speed of sound is 1100 ft/sec.
This tip speed is 759 ft/sec.

Program; Prop Optimizer, prop20.exe

Bates Engineering- The AeroOptimizer

Ref; Calculations done by Prop Optimizer for full-scale UniCopter

Program; JavaProp

Propeller Generated Vibration;

The tractor propeller and its motor are at the end of a long boom. Rotation parts must be well balanced. The boom must be very rigid.

Propeller Blade Count;

Will 3-blades provide for a smaller diameter and a more efficient induced velocity?

Controllable Propellers;

Perhaps the first question should be 'Is a controllable propeller required, considering that it is only used during cruise?'

Automatic Pitch Change Propellers; http://www.mh-aerotools.de/airfoils/javaprop.htm

See; Aircraft Propellers and Controls ~ Jeppesen, Frank Delp, Ch VII

Aeromatic Propeller:(Koppers)

My thoughts; Changing RPM maybe OK for a propeller because the low inertia of the propeller will probably convert the increased torque to PRPM quite quickly. This mechanism will probably not work for the rotor, due to its higher inertia and need for faster collective responses (i.e. UniCopter & AeroVantage).

There are 945 hits for "Aeromatic propeller" in Google.

Working Papers:

DESIGN:

MAKE:

BUY:

Secondary Group:

	General:
	Configuration:
	Trim, Stability & Control:	Information related specifically to the inclusion of a pusher prop.

Items: To be later relocated under above Secondary Group headings.

	General:

	Configuration:

	Trim, Stability & Control:

1074

Prop Suppliers etc: To be later relocated.

	Sensenich Propeller Manufacturing Company	http://www.sensenich.com
	Hartzell Propeller Inc.	http://www.hartzellprop.com/index2.htm
	MT-Propeller	http://www.mt-propeller.com
	Ivoprop	http://www.ivoprop.com
	Warp Drive Inc.
	Making a Composite Prop	http://www.icon.fi/~jtki/prop.html
	List of propeller manufacturers	http://www.ulpilot.com/contact_info.htm#Propellers

Latest revision; August 28, 2008