Forces on Solid Particles

Gyanendra · June 13, 2023, 00:26

Hello Everyone,
Problem description: I am trying to simulate erosion problem due to solid-liquid two phase flow in a pipe bend. I am using "Particle transport solid" as particle morphology. For erosion, I am using Tabakoff model for steel-quartz combination. I want to see the effects of various forces such as virtual mass, pressure gradient and turbulent dispersion on the erosion behavior of the bend. So, I am activating all those force models.

Question: After the converged solution, I want to calculate the values of these forces (virtual mass, pressure gradient and turbulence dispersion) on particles at different locations. How can I do that? Kindly, suggest.

Thank you so much.

ghorrocks · June 13, 2023, 00:52

You cannot access these variables from the solver. You will have to recalculate them by defining CEL functions which match the definition of those parameters, and sending that to an additional variable or a post processing variable if you are doing it in CFD-Post. But I would not recommend doing it in CFD-Post if you can avoid it as you will not have full access to all the solver variables.

Gyanendra · June 13, 2023, 01:10

Thank you so much, Glenn!
So, what do you suggest as an alternative?

ghorrocks · June 13, 2023, 01:33

Didn't I explain the alternative?

Quote:

You will have to recalculate them by defining CEL functions which match the definition of those parameters, and sending that to an additional variable or a post processing variable if you are doing it in CFD-Post.

Gyanendra · June 13, 2023, 01:37

Yeah,
But, you are also suggesting that you would not recommend doing that on CFD post. So, what can be the other alternative?

ghorrocks · June 13, 2023, 01:41

.... by defining CEL functions which match the definition of those parameters, and sending that to an additional variable

And the bit I should have mentioned is "In the solver"

If you are going to have a variable field you have to define an additional variable in CFX-Pre and set the variable to be a CEL expression with the function you want. Then run the solver and the variable will be in the results file. Note you might need to adjust the results file options to make sure it is included in the time steps you want.

Gyanendra · June 13, 2023, 02:18

Glenn, thank you very much for your explanation. I will try that.

June 13, 2023, 00:26	Forces on Solid Particles	#1
Gyanendra New Member Gyanendra Join Date: Jun 2023 Posts: 5 Rep Power: 2	Hello Everyone, Problem description: I am trying to simulate erosion problem due to solid-liquid two phase flow in a pipe bend. I am using "Particle transport solid" as particle morphology. For erosion, I am using Tabakoff model for steel-quartz combination. I want to see the effects of various forces such as virtual mass, pressure gradient and turbulent dispersion on the erosion behavior of the bend. So, I am activating all those force models. Question: After the converged solution, I want to calculate the values of these forces (virtual mass, pressure gradient and turbulence dispersion) on particles at different locations. How can I do that? Kindly, suggest. Thank you so much.

June 13, 2023, 00:52		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,708 Rep Power: 143	You cannot access these variables from the solver. You will have to recalculate them by defining CEL functions which match the definition of those parameters, and sending that to an additional variable or a post processing variable if you are doing it in CFD-Post. But I would not recommend doing it in CFD-Post if you can avoid it as you will not have full access to all the solver variables. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

June 13, 2023, 01:41		#6
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,708 Rep Power: 143	.... by defining CEL functions which match the definition of those parameters, and sending that to an additional variable And the bit I should have mentioned is "In the solver" If you are going to have a variable field you have to define an additional variable in CFX-Pre and set the variable to be a CEL expression with the function you want. Then run the solver and the variable will be in the results file. Note you might need to adjust the results file options to make sure it is included in the time steps you want. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Conjugate Heat Transfer: Solid Time Step in Transient Simulation, DO Model	Dingens	FLUENT	0	July 9, 2021 06:19
UDF in case with DPM modle	POSTHU	Fluent UDF and Scheme Programming	0	March 3, 2021 07:21
forces on particles	netmaster	STAR-CCM+	6	March 16, 2017 04:27
Solid Particles Injection	Azanulbizar	OpenFOAM Running, Solving & CFD	0	May 8, 2013 23:26
interaction between solid and fluid particles	agastyamit	CFX	5	November 17, 2011 07:56

June 13, 2023, 01:10		#3
Gyanendra New Member Gyanendra Join Date: Jun 2023 Posts: 5 Rep Power: 2	Thank you so much, Glenn! So, what do you suggest as an alternative?

June 13, 2023, 01:37		#5
Gyanendra New Member Gyanendra Join Date: Jun 2023 Posts: 5 Rep Power: 2	Yeah, But, you are also suggesting that you would not recommend doing that on CFD post. So, what can be the other alternative?

June 13, 2023, 02:18		#7
Gyanendra New Member Gyanendra Join Date: Jun 2023 Posts: 5 Rep Power: 2	Glenn, thank you very much for your explanation. I will try that.