Does Anyone have software to calculate Polars?
08-25-2006 | 01:00 AM
#1
Does Anyone have software to calculate Polars?
Hey Gang
I am doing a little research for my next Scale model. I will be working at 40% but don't want to use the scale airfoils for obvious reasons. Does anyone have software available to calculate the Polars for low Reynolds number airfoil sections? X-Foil or something similar and would they be willing to print out the figures for me? I am a little short on funds and can't afford the software right now, although, that is on my to do list for the forseeable future, this whole project is on a shoe string so to speak.
I am looking at a couple of Dr. Eppler's foils as well as Selig/Donovan and Wortmann. I look at the airfoil and know it is close to what I need but just want to know what the actual polars are.
If anyone would be so generous as to donate a little of their time to help out a fellow modeler, I would be very grateful. I have the plots available so that should simplify things for whomever can help.
Thanx, Wolf
I am doing a little research for my next Scale model. I will be working at 40% but don't want to use the scale airfoils for obvious reasons. Does anyone have software available to calculate the Polars for low Reynolds number airfoil sections? X-Foil or something similar and would they be willing to print out the figures for me? I am a little short on funds and can't afford the software right now, although, that is on my to do list for the forseeable future, this whole project is on a shoe string so to speak.
I am looking at a couple of Dr. Eppler's foils as well as Selig/Donovan and Wortmann. I look at the airfoil and know it is close to what I need but just want to know what the actual polars are.
If anyone would be so generous as to donate a little of their time to help out a fellow modeler, I would be very grateful. I have the plots available so that should simplify things for whomever can help.
Thanx, Wolf
08-25-2006 | 06:50 AM
#2
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From: Edmond,
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RE: Does Anyone have software to calculate Polars?
Profili:
http://www.profili2.com/eng/default.htm
Profili has a very nice friendly interface with XFoil that makes it useable for the "rest of us". I believe you need to pay a small registration fee to unlock the full XFoil interface but if you are building a 40% model, an extra €10.00 EUR is well worth the investment, and only a tiny percentage of your total cost.
If you really need someone to run the numbers for you, you might want to post root and tip chords and specific airfoils and/or thicknesses. You might also want to say what you are building a model of. There's much more to an airplane's handling than just it's section characteristics. It's a bit time-consuming to run a bunch of polar sets and I wouldn't have time personally to do that for at least a couple of weeks but maybe someone else can help sooner.
Also, the reasons for not using the scale airfoil are not obvious based on the information supplied. Some airfoils scale down just fine, depending on many factors. Airfoils that you generally do not want to scale down exactly are high-speed airfoils that have drag buckets tailored to the full-scale airplane's cruise speed. The drag bucket will not translate to model size and speed and will almost certainly not be optimum for the model and will likely provide poor low-speed handling.
http://www.profili2.com/eng/default.htm
Profili has a very nice friendly interface with XFoil that makes it useable for the "rest of us". I believe you need to pay a small registration fee to unlock the full XFoil interface but if you are building a 40% model, an extra €10.00 EUR is well worth the investment, and only a tiny percentage of your total cost.
If you really need someone to run the numbers for you, you might want to post root and tip chords and specific airfoils and/or thicknesses. You might also want to say what you are building a model of. There's much more to an airplane's handling than just it's section characteristics. It's a bit time-consuming to run a bunch of polar sets and I wouldn't have time personally to do that for at least a couple of weeks but maybe someone else can help sooner.
Also, the reasons for not using the scale airfoil are not obvious based on the information supplied. Some airfoils scale down just fine, depending on many factors. Airfoils that you generally do not want to scale down exactly are high-speed airfoils that have drag buckets tailored to the full-scale airplane's cruise speed. The drag bucket will not translate to model size and speed and will almost certainly not be optimum for the model and will likely provide poor low-speed handling.
