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@shubham jain:
I came to know where was my mistake. I was trying to create surface from sketches. I thought the 3D curve as a sketch. I tried surface from edge and got the proper surface. I could also create the domain around it after boolean subtraction. As far as my problem is concerned, its solved. But, what intrigues me is, when I import my co-ordinates after adding that 1 0 line I get sort of distorted tail of the airfoil. Please see the attached image. While with your co-ordinates I could get a perfect one. I saw that you have specifed the last y-cordinate specified by you is the same one as the first one. Only it is negative. I also find the 1 0 line missing. Can you point the logic behind it. Also, it will be very nice if you could tell how you generated so many number of points for the naca0015 profile. Is their a website or software? |
i think the distortion is due to less number of points.
it creates the curve using spline.. (i guess)..so spline with less number of points can make a mess regarding 1 0 line... as far as i know.. 1 0 line is for closing the curve.. so make i dont know how did u create a closed curve without 1 0 line in .txt file. Did u make some changes in your file. How did u make closed curve??? u can use these online generators.. i prefer these http://www.ppart.de/aerodynamics/profiles/NACA4.html http://airfoiltools.com/airfoil/naca4digit apart form these,...there must b many more available online |
NACA shapes are defined by an equation. Here is a reference to the equations: http://en.wikipedia.org/wiki/NACA_airfoil
If you use the underlying equation you can generate continuous curves and do not have to rely on gizmos which generate points. The distorted point at the end is it trying to make the sharp cusp at the end a continuous curve. It is not a continuous curve, so it have to do a weird distortion to make it continuous. You need to make sure the cusp point is kept as a cusp and not made continuous. |
@ghorrocks
Can we generate airfoil as a continuous curve (instead using points) using the equation of airfoils in ICEM CFD?? or may be in Design modeler also?? thanks in advance |
I am no expert in ICEM, I do not know if you can put in equations. I am pretty sure you cannot in DesignModeller. You probably need a high-end solid modelling package like unigraphics/ProE/Solidworks.
But you can use the equations to generate as many points as you think you need to accurately model the geometry. You also have the choice of using a few less points and a curved fit with splines, or more points and linear line segments. The linear segments are attractive as you do not need to worry about tangency issues, so the funny blob at the end of your last image will not occur. |
thanks for quick replies..
I have used CATIA. can you guide me how to create airfoils using equations in CATIA I have created airfoil using points (by importing points from excel file in catia) but i don't know if there is option to generate curve using equations in catia also?? |
That sounds like a question for a catia forum like
http://www.3dcadforums.com/catia-forum/ or http://www.eng-tips.com/threadminder.cfm?pid=560 |
@shubham:
I had added the 1 0 line at the end of the file. The explanation by ghorrocks seems satisfying to me. |
to import airfoil geometry
I could'nt import geometry , i ve tried igs,stp and prt file but it could'nt br generated.
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Error: No compatible interface found for this file type
Context: Attach Feature Import1 Error: Geometry Interface not found. Context: Attach Feature Import1 Error: Attach failed. Context: Attach Feature Import1 |
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I noticed you've helped with ansys airfoil coordinates and was hoping you'd be able to shed some light on where I'm going wrong, please? Ansys Error message: ' Error reading Coordinates File ' please find attached the coordinates file and the following link with the source for the coordinates: http://wind.nrel.gov/airfoils/shapes/S814_Shape.html thanks |
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group point 1 0 thats all. Attachment 43512 |
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this was the error message: Error: Invalid Group/ID found in coordinates file Context: POINT FEATURE POINT1 Line: 67 p.s: I've been working on solving this problem all day :/ |
Help...
Can anybody tell me..I want to import some data point of 3 different group...I've made in .txt file....But while uploading these point I got message of ......error to read it.......Is there anyone else phase this problem....Please help me How can tackle these situation.....Thanks in advance...May I know that is there any specific order of input point or it may be random.....
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I am writing under an old post! I hope somebody get back to me on this:
I am trying to create points in Geometry from Coordinate File which is attached. When I generate, a yellow tick shows up next to Points ( rather than Green) but I can see the points in the model view. In addition, I can not make line from those points. Also, when I want to make 3D Curves from the same coordinates file I receive Error reading coordinates file. Can anybody tell me what is the problem? |
I found the answer!
The reason is that my coordinates are beyond +500 and -500 meters |
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Hi guys, just stumbled across this thread so will revive it for my problem.
I'm trying to import a large number of points and need a way to connect them all together and bound them by the z axis. It is elevation data that I am trying to import. I have processed it on MATLAB and applied what has been discussed earlier to keep it between -500 and 500 for the x and y axis. I can't import my data in one as it exceeds 10000 but I've split it into different files. I find that I can import the files easily when clicking Create - Point - Create Coordinates file but when trying to create a 3D Curve (Concept - 3D Curve), I return the error message that declares that it can't read the file. I have also tried to close the curve too which hasn't help. I believe that this may be due to the points possibly intersecting with themselves but that is necessary in regards to what I need to do. Does anyone have a method that would allow me to connect all these points together? Attached an example file. |
Dear Harry,
I had the same problem as you. They only way I could sort it out was that I ordered my points based on their elevation and saved them in individual text files. Then I imported them individually and made the 3D curve manually. It was a lot of effort, but I couldn't find another way. Hope it helps. Also, make sure that the format you are using in your text file is correct! |
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3d curve
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hii,
im having issues to import the coordinates file for 3d curve. i tried putting commas as well but that didnt helped. here is my coordinates file. any suggestions? |
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