RCU Forums - Search Results
RCU Forums

Go Back  RCU Forums > Search Forums
Reload this Page >

Search Results

Register
FAQ
Calendar
Search
Today's Posts
Mark Forums Read
Vendor Directory
Notices
 
Page 1 of 17
1
2
3
11
Last »
Search: Posts Made By: adam_one
Showing results 1 to 25 of 410
Search took 0.85 seconds.
Forum: Aerodynamics
11-01-2008, 03:06 PM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

That's an interesting idea for someone with the spare time and premises to build and do the research.
It would be dynamic tests as opposed to D. Hanson's static tests.

Go for it!
;)
Forum: Aerodynamics
11-01-2008, 01:51 PM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

Your observation is correct regarding thrust as a force.
The thrust produced is equal to the sum of all the lift components of the blades sections in the direction of flight.

However, as the...
Forum: Aerodynamics
11-01-2008, 03:37 AM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

You might be right, but I guess I'm not the only one here who misunderstood the results of your test.

Nevertheless, my question is fair.
Telling us the actual prop types and sizes you've used...
Forum: Aerodynamics
10-31-2008, 05:50 PM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

Dick,
Could you tell us the actual prop types and sizes you have used that produced always the same 10oz thrust with 50W input?

Maybe you could convice helicopter manufacturers that the blades...
Forum: Aerodynamics
10-31-2008, 02:18 PM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

However, you should not disregard the motor's different efficiencies with different props.
If you use the same motor while comparing props, you have to adjust the throttle in order to get the same...
Forum: Aerodynamics
10-31-2008, 01:12 PM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

If you disregard the losses you may assume that you'll get 50W out when you put 50W in, yet the output power is never thrust only. Prop Output Power = Thrust *times* Constant *times* Pitch speed… ...
Forum: Aerodynamics
10-31-2008, 11:06 AM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

Dick,
I understand that you've performed lot of measurements with your test stand, but I wonder whether you've interpreted them right.

Thrust is only a force that is part of the prop's output...
Forum: Aerodynamics
10-30-2008, 04:33 PM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

In absence of light, darkness prevails...

;)
Forum: Aerodynamics
10-29-2008, 04:11 PM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

No confusion here.
Efficiency = Output Power / Input Power

Power is_not the same as thrust despite both are related.

Output Power = Thrust * Pitch speed

So, for a given power, the...
Forum: Aerodynamics
10-29-2008, 02:45 PM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

You say that you could fus with all kind of blades in roughly similar diameters, and so you assume that prop shapes and sizes mean very little or nuthin.

Well, just think why helicopter prop...
Forum: Aerodynamics
10-28-2008, 01:36 PM
Replies: 83
Views: 6,878
Posted By adam_one

RE: Prop pitch........ practice : theory

Watts n thrust are indeed related but prop shape and size mean a lot regarding Power/Thrust ratio.

A smaller prop requires more power to produce the same thrust as a larger one.

For...
Forum: Aerodynamics
10-04-2008, 07:31 AM
Replies: 525
Views: 38,111
Posted By adam_one

RE: [Deleted]

That's it Hugo.

The upper side of the wing is important, especially if you wish to optimise its efficiency.
You might have noticed that military aircraft's weaponry is always located...
Forum: Aerodynamics
10-30-2007, 03:48 AM
Replies: 40
Views: 4,848
Posted By adam_one

RE: Edge 540 wants to torque roll really fast when you try to hover..??? PLEASE HELP!!

Yes, but it depends much on how you want your bird to fly with the power you have available.
Focusing only on thrust may be misleading unless you’re intending to fly like a helicopter hovering...
Forum: Aerodynamics
10-29-2007, 05:02 PM
Replies: 40
Views: 4,848
Posted By adam_one

RE: Edge 540 wants to torque roll really fast when you try to hover..??? PLEASE HELP!!

Dick,

I just thought it shouldn't hurt with some definitions in order to keep the things tidy…

And believe me, a smaller prop requires more power than a larger one to produce the same...
Forum: Aerodynamics
10-29-2007, 04:47 PM
Replies: 40
Views: 4,848
Posted By adam_one

RE: Edge 540 wants to torque roll really fast when you try to hover..??? PLEASE HELP!!

I would recommend you changing to a prop with smaller diameter, but you'll need more RPM and more power to get the same thrust as the bigger one.
Forum: Aerodynamics
10-29-2007, 03:50 PM
Replies: 40
Views: 4,848
Posted By adam_one

RE: Edge 540 wants to torque roll really fast when you try to hover..??? PLEASE HELP!!

Ponder this:

A small prop requires more power (watts) to produce the same thrust as a larger one.

For instance, a 12x7 Aeronaut prop at 6000 RPM takes about 85W to produce 27 oz of thrust....
Forum: Aerodynamics
08-30-2007, 01:50 AM
Replies: 31
Views: 4,754
Posted By adam_one

RE: Prop pitch speeds

Let me show an example to illustrate what I mean with “increasing Input Power doesn't necessarily mean increasing Prop's Output Power”:

Let’s assume that you’ve got an AXI 2212/26 Gold...
Forum: Aerodynamics
08-29-2007, 02:16 PM
Replies: 31
Views: 4,754
Posted By adam_one

RE: Prop pitch speeds

:)

However, propellers of all types are referred to as screws, though those on aircraft are usually referred to as Airscrews...

Further:

The engine power delivered to the propeller =...
Forum: Aerodynamics
08-28-2007, 12:29 AM
Replies: 31
Views: 4,754
Posted By adam_one

RE: Prop pitch speeds

OK, let's quote the enquirer:


Now the right answer to that question:


A “General Rule of Thumb” might only be useful for those who are aware of its limitations.
That’s what the...
Forum: Aerodynamics
08-27-2007, 03:33 PM
Replies: 31
Views: 4,754
Posted By adam_one

RE: Prop pitch speeds

No, because it is not the prop pitch speed alone that makes the plane to move forward.
It is a combination of pitch speed and thrust, which together means power.
Forum: Aerodynamics
08-26-2007, 02:47 AM
Replies: 31
Views: 4,754
Posted By adam_one

RE: Prop pitch speeds

Yes, powered model aircraft performance may also be estimated by calculating the
weight/power ratio, also known as power loading.

A slow and low wing loading plane (for a beginner) with...
Forum: Aerodynamics
08-25-2007, 07:10 AM
Replies: 31
Views: 4,754
Posted By adam_one

RE: Prop pitch speeds

That's an interesting chart.
I've seen a similar one in Fly RC Magazine (issue 10, Sept. 04) by Andy Lennon.

But for those who like typing figures on a computer, may try following:

...
Forum: Aerodynamics
08-24-2007, 02:49 PM
Replies: 31
Views: 4,754
Posted By adam_one

RE: Prop pitch speeds

Maybe explanation of some definitions might be of interest...

Geometric Pitch is the distance an element of a prop should
advance in one revolution if there was no slip.

Mean Geometric...
Forum: Aerodynamics
03-13-2006, 04:08 PM
Replies: 34
Views: 10,884
Posted By adam_one

RE: anhedral on horizontal stab

Another reason for anhedral on horizontal tail might be to increase the projection area of the vertical fin, improving directional stability.
Forum: Aerodynamics
01-27-2006, 07:16 AM
Replies: 53
Views: 3,733
Posted By adam_one

RE: Buoyancy (Sorry)

kriegsmacht,
It seems that you don't fully understand the physics laws...
Let's try to explain:
The air, just like any other matter is capable to react against a force applied upon it.
For...
Showing results 1 to 25 of 410
 
Page 1 of 17
1
2
3
11
Last »


 
Forum Jump

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.