Dear all,
Greetings of the day!
I am interested in modeling of unit cell of woven fabric composite (2x2 twill weave and plain weave) in ABAQUS in order to determine the effective elastic constants of woven composite laminate from its individual constituent properties (fibre+matrix). Now after modeling of unit cell in TEXGEN further analysis is required in ABAQUS for calculating the elastic constants. I am not clear about the calculation of elastic constants from constituent properties (fibre+matrix) of unit cell in ABAQUS and would further like to request you all to kindly provide me any solved example problem or any useful study material or any useful link if possible, pertaining to analysis of above said problem in ABAQUS. Solved example problem will be highly appreciated.
I have prepared the voxel mesh model in TEXGEN and imported the same ABAQUS.
Best Regards
Thanking You
Mukesh Kumar
Calculation of effective elastic constants(9 constants)
Moderators: Martin, Developers
Re: Calculation of effective elastic constants(9 constants)
Hello Mukesh,
You can use the scripts provided with the TexGen distribution to calculate elastic properties. Details are given here: http://texgen.sourceforge.net/index.php ... and_Abaqus
Hope that helps,
Louise
You can use the scripts provided with the TexGen distribution to calculate elastic properties. Details are given here: http://texgen.sourceforge.net/index.php ... and_Abaqus
Hope that helps,
Louise
Re: Calculation of effective elastic constants(9 constants)
Dear Louise
First of all thanks for the reply.
I have gone through the web page (http://texgen.sourceforge.net/index.php ... and_Abaqus) as suggested by you. I have run the program as advised and tried to validate the paper (S.-P. Ng, P.-C. Tse, K.-J. Lau, Numerical and experimental determination of in-plane elastic properties of 2 X 2 twill weave fabric composites. Compos. B 29, 735–744 (1998)) but the results obtained from the run program via Abaqus command line are showing variation with the paper. I am attaching the snapshot of the properties used and my result obtained after running the program from the Abaqus command line for your reference. Please suggest.
Thank You
Mukesh Kumar
First of all thanks for the reply.
I have gone through the web page (http://texgen.sourceforge.net/index.php ... and_Abaqus) as suggested by you. I have run the program as advised and tried to validate the paper (S.-P. Ng, P.-C. Tse, K.-J. Lau, Numerical and experimental determination of in-plane elastic properties of 2 X 2 twill weave fabric composites. Compos. B 29, 735–744 (1998)) but the results obtained from the run program via Abaqus command line are showing variation with the paper. I am attaching the snapshot of the properties used and my result obtained after running the program from the Abaqus command line for your reference. Please suggest.
Thank You
Mukesh Kumar
- result.jpg (217.05 KiB) Viewed 18477 times
Re: Calculation of effective elastic constants(9 constants)
Hi Mukesh,
I would guess that you need to check whether you have created your model to accurately represent the textile in the paper. Also, are the yarn properties given for the yarn by itself? Have you assumed a constant volume fraction for the yarns, in which case you will need to use the appropriate properties, or are you using the volume fractions in the .eld file in which case you will need a UMAT to give the local yarn properties.
Also, have you done any sort of sensitivity study to make sure that you have used an appropriate size voxel for your model.
Hope that helps,
Louise
I would guess that you need to check whether you have created your model to accurately represent the textile in the paper. Also, are the yarn properties given for the yarn by itself? Have you assumed a constant volume fraction for the yarns, in which case you will need to use the appropriate properties, or are you using the volume fractions in the .eld file in which case you will need a UMAT to give the local yarn properties.
Also, have you done any sort of sensitivity study to make sure that you have used an appropriate size voxel for your model.
Hope that helps,
Louise
Re: Calculation of effective elastic constants(9 constants)
Dear Louise,
Thanks for your reply,
as suggested i checked my .ELD file and observed that volume fraction for yarn throughout the analysis is zero and that needs to be assigned rationally in order to obtained correct results. Now my question is that, is there any other method/alternative way to assign volume fraction of yarn directly in TexGen rather than going for UMAT. If yes then please suggest me else give me some hints to develop UMAT.
Thanks & Regards
Mukesh Kumar
Thanks for your reply,
as suggested i checked my .ELD file and observed that volume fraction for yarn throughout the analysis is zero and that needs to be assigned rationally in order to obtained correct results. Now my question is that, is there any other method/alternative way to assign volume fraction of yarn directly in TexGen rather than going for UMAT. If yes then please suggest me else give me some hints to develop UMAT.
Thanks & Regards
Mukesh Kumar
Re: Calculation of effective elastic constants(9 constants)
Hi Mukesh,
If the volume fractions in the .eld file are zero that suggest that you may not have set up the material properties correctly in TexGen. The volume fraction is calculated using the fibre information. You need to input fibre area, or fibres per yarn and fibre diameter, or yarn linear density and fibre density. You need at least one of those three sets of information and then TexGen will automatically calculate the volume fraction for each element and output in the .eld file.
There is a sample UMAT supplied with the TexGen installation. There is a lot of useful information on using TexGen in the documentation on the website http://texgen.sourceforge.net/index.php/Documentation including instructions on how to use the UMAT.
Hope that helps,
Louise
If the volume fractions in the .eld file are zero that suggest that you may not have set up the material properties correctly in TexGen. The volume fraction is calculated using the fibre information. You need to input fibre area, or fibres per yarn and fibre diameter, or yarn linear density and fibre density. You need at least one of those three sets of information and then TexGen will automatically calculate the volume fraction for each element and output in the .eld file.
There is a sample UMAT supplied with the TexGen installation. There is a lot of useful information on using TexGen in the documentation on the website http://texgen.sourceforge.net/index.php/Documentation including instructions on how to use the UMAT.
Hope that helps,
Louise