[ziadkoussa]

I have a simple case to model however I am constantly getting errors.

Given a copper pipe with interior diameter 4.75mm and outer diameter 6mm, water flowing at velocity 0.3m/s through the pipe at 293K. The pipe has a constant heat flux of 166W/m^ 2.


I tried running an extruded circle (cylinder) with 4.75mm diameter and then applied a heat flux of 166 with a wall thickness of 1.25mm. I also tried running a pipe (two circles at 4.75mm and 6mm which were then extruded). Also, a cylinder with the BC at the wall to have shell conduction set to 1 layer at 1.25mm.

For the cylinder cases, I applied an inflated mesh.

However, for all these results, I would not get the expected temperature profile.

[AlexanderZ]

may be the problem is your expectations

best regards

[davex1234]

Did you define the volume surrounding the pipe? Heat flux is dependent on the delta T. Q = h A dT

[ziadkoussa]

no i did not

i just modelled the pipe itself.

i varied the conditions a bit making them the same as those found in literature.
I applied a heat flux of 10^6 W/m.m and an inlet temperature = 273K at 3m/s

[davex1234]

If you do not define a fluid with a given temperature outside the pipe it can only transfer energy through radiation. The fluid (assuming air in this case) is required for conduction simulations.

[MIDHUN@CFD]

please give inflation and set wall y plus less than 5 or close to 1 if possible and retry