Eulerian model with ideal gas

dean993 · November 30, 2021, 02:47

Hi,

I am modelling a fluidized bed using the Eulerian method. The basic model (fixed gas density) runs without no problems but when I implement the density of air to be calculated using the compressible ideal gas equation, I am getting the following errors:

reversed flow in 82 faces on pressure-outlet 8.
Stabilizing pressure correction to enhance linear solver robustness.
6 1.4665e+00 4.4163e-03 5.3608e-03 5.1322e-01 6.0217e-01 3.0762e-03 0:00:08 54
Stabilizing pressure correction to enhance linear solver robustness.
Divergence detected in AMG solver: pressure correction
Error at host: floating point exception

Error at Node 0: floating point exception

Please let me know if you have any suggestions to fix this issue.
Thank you.

cbooks77 · December 1, 2021, 18:25

Read the fluent documentation on well posed compressible flow boundary conditions it sounds like you dont have the correct boundary conditions specified like correctly setting the operating density etc.. Also you need to run the transient solver the steady solver will not work.

dean993 · December 1, 2021, 18:28

Hi Chris, The Eulerian model only works with the pressure-based solver and I am running the model transiently. I did manage to get the model running by first allowing the solution to run with a fixed density and then using that data file to run with the ideal gas model, but over time it tends to crash.

November 30, 2021, 02:47	Eulerian model with ideal gas	#1
dean993 New Member Dinushke Join Date: Aug 2013 Location: Victoria, Australia Posts: 13 Rep Power: 12	Hi, I am modelling a fluidized bed using the Eulerian method. The basic model (fixed gas density) runs without no problems but when I implement the density of air to be calculated using the compressible ideal gas equation, I am getting the following errors: reversed flow in 82 faces on pressure-outlet 8. Stabilizing pressure correction to enhance linear solver robustness. 6 1.4665e+00 4.4163e-03 5.3608e-03 5.1322e-01 6.0217e-01 3.0762e-03 0:00:08 54 Stabilizing pressure correction to enhance linear solver robustness. Divergence detected in AMG solver: pressure correction Error at host: floating point exception Error at Node 0: floating point exception Please let me know if you have any suggestions to fix this issue. Thank you.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Removing Real Gas Model	zwong8	FLUENT	0	August 17, 2021 11:42
Table bounds warnings at: END OF TIME STEP	CFXer	CFX	4	July 16, 2020 23:44
Gas Stirred ladle Eulerian model	Surinder	Fluent Multiphase	0	April 29, 2016 04:07
IDEAL GAS: not fulfilled even though set up?	Fettmon	FLUENT	4	November 3, 2015 07:32
Wrong flow in ratating domain problem	Sanyo	CFX	17	August 15, 2015 06:20

December 1, 2021, 18:25		#2
cbooks77 New Member Chris Join Date: Mar 2021 Posts: 23 Rep Power: 5	Read the fluent documentation on well posed compressible flow boundary conditions it sounds like you dont have the correct boundary conditions specified like correctly setting the operating density etc.. Also you need to run the transient solver the steady solver will not work.

December 1, 2021, 18:28		#3
dean993 New Member Dinushke Join Date: Aug 2013 Location: Victoria, Australia Posts: 13 Rep Power: 12	Hi Chris, The Eulerian model only works with the pressure-based solver and I am running the model transiently. I did manage to get the model running by first allowing the solution to run with a fixed density and then using that data file to run with the ideal gas model, but over time it tends to crash.