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Steady state solution as an initial condition for a transient problem

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Old   January 16, 2015, 17:21
Default Steady state solution as an initial condition for a transient problem
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Adnan
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I am relatively new to FLUENT and have a question on solution initialization of a transient problem.
I am working on a transient problem which involves a fluid and a solid domain. (Similar to a quenching problem)

The initial analysis that I did involves only the heat transfer in the fluid domain. For this case, I found out the steady state heat transfer solution.

The next step involves the transient heat transfer in both fluid and solid domains. I want to give the steady state solution in the fluid as my initial condition. The solid is at a fixed temperature initially.
When I look in the FLUENT options for solution initialization, I can only patch the liquid domain to a fixed temperature.
Is there a way by which I can import the results of my steady state solution as an initial solution for the transient case?

Thanks
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Old   January 17, 2015, 00:16
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Quote:
Originally Posted by adnanakhtar View Post
I am relatively new to FLUENT and have a question on solution initialization of a transient problem.
I am working on a transient problem which involves a fluid and a solid domain. (Similar to a quenching problem)

The initial analysis that I did involves only the heat transfer in the fluid domain. For this case, I found out the steady state heat transfer solution.

The next step involves the transient heat transfer in both fluid and solid domains. I want to give the steady state solution in the fluid as my initial condition. The solid is at a fixed temperature initially.
When I look in the FLUENT options for solution initialization, I can only patch the liquid domain to a fixed temperature.
Is there a way by which I can import the results of my steady state solution as an initial solution for the transient case?

Thanks
I have a solution in my Evernote but actually i haven't tried it yet, so if something is wrong, please correct me.
You may do this:
File-Write-Case&Data;

File-Interpolate;

ScreenClip1.jpg

Write data and store a .ip file;
then Read and Interpolate with that .ip file.
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Old   January 17, 2015, 00:21
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.....Just after I reply with that solution, I realized that method applies to interpolating data between different mesh solutions...Now I think maybe File-Read-Data will do......
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Old   January 17, 2015, 04:06
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Quote:
Originally Posted by adnanakhtar View Post
I am relatively new to FLUENT and have a question on solution initialization of a transient problem.
I am working on a transient problem which involves a fluid and a solid domain. (Similar to a quenching problem)

The initial analysis that I did involves only the heat transfer in the fluid domain. For this case, I found out the steady state heat transfer solution.

The next step involves the transient heat transfer in both fluid and solid domains. I want to give the steady state solution in the fluid as my initial condition. The solid is at a fixed temperature initially.
When I look in the FLUENT options for solution initialization, I can only patch the liquid domain to a fixed temperature.
Is there a way by which I can import the results of my steady state solution as an initial solution for the transient case?

Thanks
hey Adnan!
Did you run a steady state simulation in fluent!?
if yes, of course that you can use these data for the transient simulation...
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Old   January 17, 2015, 14:06
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Thank you for the reply Amin and Soriyoshi.

Yes, I was able to run the steady state problem.

The file read data would not work as it has 2 different meshes. (the steady state one with only the fluid and the transient one that I have with both the solid and fluid domains)
So when I tried file read data I got an error saying the mesh is different.

When I tried running the case by using the interpolation file, one problem that I faced was the values initialized weren't the same as the steady state solution. Instead a different fixed temperature was initialized in the liquid domain. Probably, because the coordinates of the steady state problem and the transient problem are different. I am not sure about this?

Is there a way by which I can specify the coordinates of the region where the interpolation file should initialize the data?
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Old   January 19, 2015, 14:26
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Hi,

I resolved the problem by solving the steady problem in the new domain by giving adiabatic conditions on the interface between the solid and liquid domain.
I used that as my initial conditions and got the desired results.

Thanks
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Old   October 24, 2016, 14:01
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Hello every one, I have a similar problem here. I am simulating water hammer in a pipe. The flow is turbulent so I simulated the flow first for steady state before a sudden closure of the exit valve.

The B.C were a fixed static pressure at inlet, and a fixed flow rate at exit

I need to use these conditions (including the generated velocity profile) as initial conditions for the transient simulation when the valve is suddenly closed.
The B.c I want to use are : the same static pressure at inlet and 0 velocity at outlet ( or maybe 0 flow rate at outlet)

I am not sure how I can do that in fluent.

Thank you in advance for your help.
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Old   November 25, 2016, 06:16
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Quote:
Originally Posted by M.Meki View Post
Hello every one, I have a similar problem here. I am simulating water hammer in a pipe. The flow is turbulent so I simulated the flow first for steady state before a sudden closure of the exit valve.

The B.C were a fixed static pressure at inlet, and a fixed flow rate at exit

I need to use these conditions (including the generated velocity profile) as initial conditions for the transient simulation when the valve is suddenly closed.
The B.c I want to use are : the same static pressure at inlet and 0 velocity at outlet ( or maybe 0 flow rate at outlet)

I am not sure how I can do that in fluent.

Thank you in advance for your help.
Any updates?
I am going to conduct a similar numerical model.
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