i was working on the Tutorial: Conjugate Heat Transfer in a U-Tube Heat Exchanger. I’ve done every mentioned step but i could not achieve the same result as depicted on the website. This is what my result looks like including a cutting plane:
Hi there!
Thank you for pointing this out. Actually you are using the correct properties for water, and in the tutorial air properties are used instead. This has an effect on the results of course. Other than that your project setup is just fine, only the tutorial needs an update
I noticed the sample problem as Swagler. When the fluid density is assumed to be constant the results do not me sense to me.
The picture below shows the temperature profile for the inner fluid (water) entering at 35oC. According to this picture, the fluid warms up and then leaves the tubes almost at the same temp as the inlet, which makes no sense to me.
Tsite, could you please help me to understand why that is happening?
I changed the the equation of state to perfect gas instead of constant density and the results make more sense to me, see picture below. The water enters at 35oc and leaves the tubes at about 39oc, which makes sense. Looking forward to hearing from you. Thanks.
If you are applying a gas (e.g., air), then you can use the ‘Perfect gas’ equation.
If you are using a liquid (e.g., water), then choose the ‘Rho constant equation of state fluids constant transport’ option and specify the fluid density manually.
As mentioned above, the original document has an error, as it uses the properties of air, that should be treated as a perfect gas.
Another approach is to apply water properties to the cooling stream, and air properties to the hot stream, have a look at the corresponding results here:
You can still see that the cold stream is not affected a lot, but by introducing different conditions and material properties, there could be a significant difference
i was working on the Tutorial: Conjugate Heat Transfer in a U-Tube Heat Exchanger. I used air and water as fluid as mention in the tutorial but still i don’t see the same result as tutorial. Temperature distribution on the coolant (water) does not matches with the tutorial.
The tutorial is currently being updated by the team. Once the update is complete, the solution fields presented in the documentation will reflect the effects of the latest product updates on the SimScale platform.
