I am using CFX for simulating fluid flow and heat transfer of PCHE . The fluid used is Supercritical CO2 and for importing properties we are usig polynomial equations. The data is taken from NIST database.We are getting "ERROR: Floating point exception: Overflow" after three iterations and the error disappears when some other default fluid is used.
I look forward for valuable advices in this regard
You should have mentioned a bit more about flow and solver parameters to help with the diagnosis.
I have few suggestions :
1. Check whether your polynomial equations are giving correct properties.
2. Try running with first order.
3. Try to vary CFL number and check if it runs with lower time step.
4. Try changing the flux schemes.
As I said, it's a bit difficult to make comments without knowing the flow conditions and schemes used.
Hope this helps.
Anant
I would say, that usually one can get an overflow, if there is a division by zero or other ridiculous number (1e-38) (in both cases, some property might be unavailable somewhere or under some conditions). Maybe You should check the continuity of the CO2 properties.
I suggest you:
1. In the simulation, change the flux scheme and check that your polynomial equations give the correct properties.
2. Change the CFL number and make sure it works with time.
All the best and happy
- Badges
- Science topic
- Similar topics
- Engineering
- Thermal Engineering
- Thermofluid
- Heat Transfer