XFLR 5 Newbie

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charminbaer

New Member
Joined
Oct 28, 2013
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4
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Germany
Hey,

I'm new to XFLR5, and am looking for a solution for showing only a single curve in the polar view. Right now, I'm looking at 150 different curves for 150 Reynold-Numbers. How can I change that?
In other terms, why does nothing happen when I select a different airfoil in the dropdown menu? (It says TsAGI R-3a 14% in the concerning dropdown menu)

I hope you can help me.
Cheers!
MariusXFLR5.jpg
 

Birdman100

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Jun 12, 2013
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807
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Novi Sad, Vojvodina
Ctrl+1=define an airfoil (or choose NASA, Tsagi, etc..)

Ctrl+5= airfoil analyze...

Select "Analysis", than "Define an Analysis" (F6).. This is if you want to analyse one airfoil at one Re.

I think your XFLR is set to "Batch Analysis" by default.
 

charminbaer

New Member
Joined
Oct 28, 2013
Messages
4
Location
Germany
Tanks for the answer, that actually helps.
But what if i analyzed hundreds of Reynolds-Numbers, and they are all shown in the window, and I only want to display a special one?
 

Birdman100

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Jun 12, 2013
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Im not sure if there is that possibility, XFLR is a simple program, especially GUI. Try to find answer, or post question here.

May I ask you: why do you need to analyze hundreds of Re numbers?
 
Joined
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Rocky Mountains
It's a given task by my professor - I don't know either ;-)

We called that "busy work" when I was in grade school. :bored:

The only way to do what you want to do, that I can think of using XFLR5, is to break the project into a set of batches, and save them as different projects. If you need a clean graph of only one Re # then you are going to have to save it as it's own project.

You might be able to build a program in something like Mathcad using the underlying XFOIL foundation? You can then build a 3D graph, display any single Re number or just about any other output you might need.
 

charminbaer

New Member
Joined
Oct 28, 2013
Messages
4
Location
Germany
Thx for the help so far! I was able to get it working.

Another question: I'm trying to do a viscous 3D Panel analysis for my model plane. For AOA -5° to 8.8° it works just fine. Then, i get this error message:

Code:
Computing Plane for alpha=   9.00°
[/FONT] [FONT=Courier]       Calculating aerodynamic coefficients...[/FONT]
 [FONT=Courier]         Calculating wing...An-2 vereinfacht_Wing[/FONT]
 [FONT=Courier]         Calculating wing...An-2 vereinfacht_Wing2[/FONT]
 [FONT=Courier]         Calculating wing...An-2 vereinfacht_Elev[/FONT]
 [FONT=Courier]           Span pos =     -8.14 mm,  Re =   225 000,  Cl =   1.01 could not be interpolated[/FONT]
 [FONT=Courier]           Span pos =      8.14 mm,  Re =   225 000,  Cl =   1.01 could not be interpolated[/FONT]
 [FONT=Courier]         Calculating wing...An-2 vereinfacht_Fin[/FONT]
 [FONT=Courier]       Calculating body...[/FONT]

...and the same for the AOAs to come. Any suggestions?
 

John Newton

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Joined
Dec 5, 2012
Messages
430
Location
Derbyshire, England
I would suggest either you have gone beyond the range at which you ran your initial airfoil batch analysis or the airfoil is stalled at that point and therefore XFLR5 was unable to interpolate a result for that Re no. and Cl for that give airfoil at that span position along your wing, hope this helps.

John
 

Aerowerx

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Dec 1, 2011
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Marion, Ohio
I would suggest either you have gone beyond the range at which you ran your initial airfoil batch analysis or the airfoil is stalled at that point
+1 on that.

I have seen that myself.

Charminbaer, are you calculating singe points or a sequence of AoA points? If you using a sequence, you can actually see if it is approaching stall, as the 'error' that you get start at the center of the wing and spread towards the tip at higher angles (assuming washout is used).

You also need to compute the foil curves at two Reynolds number , one on either side of the data point in question. Of course, the more points you have the more accurate the results.
 

pictsidhe

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Jul 15, 2014
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Location
North Carolina
Is there a manual for this anywhere? I'm trying to work out how to use it and am just getting errors, I can't find any documentation.
 
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