What is relation between CGAPS and Contact conduction?

Altair Forum User

Hello friends,

 

I have implemented contact Interface between Hexa and tetra mesh with contact surface, and also using CONT Properties with PCONTHA activate and value also put in KC = 1000000, now In my model I have also introduced CGAPS which is not in contact area, just defined CGAPS for mechanical friction and for mechanical Analysis, but because of CGAPS I can't get right thermal results. without CGAPS I got right thermal means temperature field.

I am curious to want to know how CGAPS affects on my contact Interface and contact Card?

 

Make on Notice: where I have applied CGAPS there not any thermal Transfer or contact thermal Transfer. so may be not Need to apply PCONTHT Card.

 

Thank you,

 

Regards,

Jay

Rahul Rajan_21763

It would be nice if you can share Model & results files with us for better understanding.Use ftp link available in my signature.I hope you would have read commments of PCONTHT card from user guide.Just Sharing FYR.

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Rahul Rajan_21763

Thanks for sharing files.PFA screenshot for contact based thermal analysis & fem file for your reference. Please run same in latest version.

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Altair Forum User

Hello Rahul, yesterday I have send one another file with One more component with CGAPS. As in your model I wnat to implement like around your Pipes or geometry one hollow circular pipe and inbetween there is CGAPS; by assuming the inside geometry is moving. The main question is CGAPS I have used for mechanical Friction or mechanical load step, but it affects also in my Thermal load step. Temperature goes up. And it affects Mechanical stresses too. Make sure I am doing Thermo-Mechanical analsis so Temperature which I got from Thermal load step I have to use in Mechanical load step. which I have already mentioned. Please correct my Problem.

Rahul Rajan_21763

Apply thermal contact via PCONT instead of creating CGAP elements.Also without checking your orignal file it would be difficult to comment. 

Altair Forum User

I am using Contact-based Thermal Analysis, so I have already used PCONT in my model, CGAPS are not where I have defined contact conduction or Contact Interface. Still I can't understand how It affected my temperature results. CGAPS use for friction I have already send you Pictures.

 

I hope you can undertand my Problem.

Rahul Rajan_21763

I got your problem.I will check internally & update you soon.

Rahul Rajan_21763

Also if it possible to share screenshot of Temp output/PCONT/CGAP parameter then please do share.

Rahul Rajan_21763

Please make sure to use PGAPHT which is required for CGAPG in thermal analysis.Also naming which you have used as CGAPS confuses me.I took it as CGAPG.

Altair Forum User

Hi Rahul, I got solution of my problem. I have to put value inside the PGAPTH, the value of Lemda. In   PGAPHT thermal based Contact case I have to fill  KAHT  = almost zero. CGAPS I am using for mechanical case but when we use couple Analysis then We should also add PGAPHT activate and put Zero in KAHT.

 

Thank you for your Support.

 

Thank you.

Rahul Rajan_21763

Thanks for the update.