×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

surface heat flux problem

surface heat flux problem

surface heat flux problem

(OP)
hi all
i am doing a thermal analysis on a spindle. spindle got bearings inside. i did some tests on the real machine and i got the temperatures on the spindle surface as 27C running the machine for 1 hour. ambient temp was 23.5C. i dont know the bearing temp because of no access to the bearings, niether i want to apply temperature BC on the bearings because i want a gradual increase with time in thermal graph.

now to replicate i am applying surface heat flux in Abaqus. i calculated surface heat flux using q=kdt/L which can calculate 1D heat flux and it is obtained to be a bit high. Another option to use is Q=mcpdt which can calculate Energy but Abaqus only allows to put surface, body or concentrated heat fluxes. As my model in 3D could any one knows
1) how surface heat flux would be calculated?.
2) Could Q=mcpdt be used for it?

I would be grateful if i get any answers to this
Regards
 

RE: surface heat flux problem

If the heat flow is predominantly 1D then calculating kdt/dx at one surface will give you the heat flux. You'd obviously have to measure an internal temperature too to get the temperature gradient. Alternativly if you know the heat transfer coefficient then kdt/dx=h(Ts-Ta). The heat flux at one surface will be the same heat flux at the other for 1D heat flow. The expression for Q=mCpdt is for mass flow past a surface, if my memory is correct, which I don't think is applicable.  

corus

RE: surface heat flux problem

(OP)
hi
thanks corus for your valuable suggestion. i first try to know what my internal temperautre is by some means.

Regards
 

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources