Yarn gap

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dyeyanie
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Yarn gap

Post by dyeyanie »

Hi Louise,

I resubmit my previous question here.

As referred to the subject, I'm trying to define the yarn spacing/gap between two yarns on the top and bottom part for a single layer fabric. I inserted my yarn spacing in weave wizard as 1 in which to my understanding, that refers to the side-to-side spacing (horizontal gap). Am I right? If Yes, how about the gap for vertical side?

Yanie
louisepb
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Location: Nottingham

Re: Yarn gap

Post by louisepb »

Hi Yanie,

For a single layer fabric I assume that you are using the 2D wizard. In this case the yarn spacing gives the gap between adjacent warp or weft yarns. If you want to specify a gap between the yarns vertically (ie where they cross over each other) then you will need to specify the "Gap size" which is used in conjunction with the refine option.

Louise
dyeyanie
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Re: Yarn gap

Post by dyeyanie »

Hi Louise,

Yes u are right.I'm using 2d weave to generate 3D weave because I'm using the old method to do this (before you come out with 3D weave option.) So how could I check this gap since I'm using the old steps? What's the default value for this gap size if we selected the 3D options?

Yanie
louisepb
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Re: Yarn gap

Post by louisepb »

Hi Yanie,

I think I misunderstood you. My recollection of a sample fabric that you posted on the forum was of a 2D fabric and therefore I assumed that this was still what you are working on. Unfortunately, if you're using the 3D option within the 2D wizard then, as you will see the refine and gap size options are greyed out as there is no refine implemented for the 3D weaves.

Louise
dyeyanie
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Joined: Thu Oct 06, 2011 10:39 am

Re: Yarn gap

Post by dyeyanie »

Hi Louise,

Actually I'm still working on that geometry but I created them in 3D without enforcing the binder to them. . So, according to your elaboration it seems that I couldn't determine the gap size right?Is there any alternatives to do it?

Yanie
louisepb
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Location: Nottingham

Re: Yarn gap

Post by louisepb »

Hi Yanie,

If you're still working on this geometry then I don't understand why you're using a 3D weave - this is a 2D weave and therefore you can enforce the gap between the upper and lower surfaces of the yarns by using the refine option and specifying the gap.

Louise
dyeyanie
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Posts: 154
Joined: Thu Oct 06, 2011 10:39 am

Re: Yarn gap

Post by dyeyanie »

Hi,

Owh no, it seems like I'm the one who misunderstood the terms that you use. That means i already made a wrong choice to my geometry. But I thing this will not affect the analysis since no binder is created in this geometry. Am i right?

Yanie
louisepb
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Location: Nottingham

Re: Yarn gap

Post by louisepb »

Hi Yanie,

Everything should be ok - I assume that you used the 3D option but then didn't add any extra layers? Everything will basically be the same but, because there is no refine option, you don't have the option of specifying a gap between the surfaces. (Also it won't have tried to avoid any intersections between yarns ).

Louise
BoB_from_jungle
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Joined: Tue Sep 22, 2015 3:31 am

Re: Yarn gap

Post by BoB_from_jungle »

Dear TexGen Team!
thank you for your software.
I want to predict the permeability of unit cell my fabric. It's 4-H harness satin and unit cell consist of 1 layer. Unfortunately, I couldn't understand what does mean "yarn spacing" and "gap size". Yarn Spacing - by default this is the same for both warp and weft yarns, it is suit only for balanced fabric. Yarn Width - by default this is the same for both warp and weft yarns. How can I change these parameters? Well you know that almost everything fabric are anisotropic because they have different width/hight ratio.
Image
louisepb
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Location: Nottingham

Re: Yarn gap

Post by louisepb »

Hi,
The User Guide here: http://texgen.sourceforge.net/index.php ... e_2D_Weave gives details of how to change individual yarn widths, spacings etc.
In the 2D wizard the yarn spacing is defined as the distance from the edge of the yarn to the equivalent edge on the adjacent yarn. So, for example, in your diagram the left hand set of arrows should be pointing at the left hand edge of the yarn.

The gap size is used in the refine function and specifies a gap to be created between warp and weft yarns at the contact surfaces. If the gap is zero then the yarns are just in contact with each other. This can be specified if needed to make sure that there is no interference between the two yarns.

I hope that helps,
Louise
maryam_sodagar
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Re: Yarn gap

Post by maryam_sodagar »

louisepb wrote:Hi Yanie,

For a single layer fabric I assume that you are using the 2D wizard. In this case the yarn spacing gives the gap between adjacent warp or weft yarns. If you want to specify a gap between the yarns vertically (ie where they cross over each other) then you will need to specify the "Gap size" which is used in conjunction with the refine option.

Louise
Dear Louise

Thank you for your help.
Would you please be more specified how we can set the vertical gap size? because when I am doing the mechanical test, no matter what is the friction coefficient so I think yarns do not have a surface contact with one another. (Also they do not intersect) I want to make them just touch each other so what should I do?

Thank you,
louisepb
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Posts: 998
Joined: Tue Dec 08, 2009 2:27 pm
Location: Nottingham

Re: Yarn gap

Post by louisepb »

Hi Maryam,

The gap size is specified in the 2Dwizard as shown here: http://texgen.sourceforge.net/index.php ... e_2D_Weave If you're creating your textile using a script then you can set it using the weave.SetGapSize() function. If you set it to zero then the yarns will just touch.

I don't entirely understand your question: If you have a woven fabric then there will be surface contacts between the woven yarns and therefore the coefficient of friction need to be specified in your simulation.

Best regards,
Louise
maryam_sodagar
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Joined: Sun Jun 21, 2015 1:28 pm

Re: Yarn gap

Post by maryam_sodagar »

louisepb wrote:Hi Maryam,

The gap size is specified in the 2Dwizard as shown here: http://texgen.sourceforge.net/index.php ... e_2D_Weave If you're creating your textile using a script then you can set it using the weave.SetGapSize() function. If you set it to zero then the yarns will just touch.

I don't entirely understand your question: If you have a woven fabric then there will be surface contacts between the woven yarns and therefore the coefficient of friction need to be specified in your simulation.

Best regards,
Louise
Dear Louise
Thanks.
But what if I do not create my textile using a script? I generated it using texgen wizard. Can i edit the tg3 file?
I apologize if I am disturbing you.
louisepb
Project Leader
Posts: 998
Joined: Tue Dec 08, 2009 2:27 pm
Location: Nottingham

Re: Yarn gap

Post by louisepb »

Hi Maryam,

As described in the link in the previous reply you can set the gap size in the 2DWizard. This is then used to generate the textile which is what will then be saved in the tg3 file. It is possible to edit the tg3 file but in this case it will be too late and won't help you.

Hope that helps,
Louise
maryam_sodagar
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Joined: Sun Jun 21, 2015 1:28 pm

Re: Yarn gap

Post by maryam_sodagar »

I have opened the tg3 file with notepad and saw that the gapsize is 0. So if I do not edit the gapsize it will remain zero? (I need it to be 0)
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