Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Thermal resistance in non-isothermal pipe flow (nipfl)

Please login with a confirmed email address before reporting spam

Gooday,

I'm using non-isothermal pipe flow model and heat transfer in solids physics in order to simulate a bore hole heat exchanger (BHE). the problem consist of a tube modeling by nipfl and a ground around the tube modeling as a solid heat transfer. The program seems to simulate the problem in a reasonable way but when the thermal resistance (R) is calculated, the obtained R by Comsol is higher almost 30 % compared with R obtained by formula or 2D model. I guess since this module simulate the pipe flow as a 1D problem and there is a gap between the pipe and solid which in graphics shows as a solid part, it adds the value of thermal resistance. Can anyone help or has a suggestion?

In attachment you can find the file.

kind regards,
Amin


2 Replies Last Post 2016年9月12日 GMT-4 07:08
COMSOL Moderator

Hello Amin Jahanbin

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.


Please login with a confirmed email address before reporting spam

Posted: 8 years ago 2016年8月28日 GMT-4 17:27
Dear Mr. Jalabin,

right now i'm still in research for modelling heat transfer in geothermal system using nipfl and heat transfer in solid. My research is about predicting the temperature of reservoir time dependent. I've got similar problem, heat transfer between pipe and solid ground is too fast and i think the problem is the same with yours. Can anyone help or give a suggestion ?

thank you
Dear Mr. Jalabin, right now i'm still in research for modelling heat transfer in geothermal system using nipfl and heat transfer in solid. My research is about predicting the temperature of reservoir time dependent. I've got similar problem, heat transfer between pipe and solid ground is too fast and i think the problem is the same with yours. Can anyone help or give a suggestion ? thank you

Please login with a confirmed email address before reporting spam

Posted: 8 years ago 2016年9月12日 GMT-4 07:08
Dear Qiva,

I changed my using module (nipfl to ht). Because as far as I could see, it was not an appropriate one for predicting such sensitive term like thermal resistance. Now, i am using the module of heat transfer in fluid and solids and it did work.

Hope it help you too.

Kind regards,
Amin Jahanbin
Dear Qiva, I changed my using module (nipfl to ht). Because as far as I could see, it was not an appropriate one for predicting such sensitive term like thermal resistance. Now, i am using the module of heat transfer in fluid and solids and it did work. Hope it help you too. Kind regards, Amin Jahanbin

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.