Tutorial: To simulate Hagen-Poiseuille flow in OpenFOAM.
Script and Narration : Saurabh S. Sawant
Keywords: Video tutorial,CFD.
|Slide 1:||Hello and welcome to the spoken tutorial on simulating Hagen-Poiseuille flow in OpenFOAM|
| Slide 2 : Learning Objectives
|| In this tutorial we will see:
|Slide 3: System Requirement|| To record this tutorial, I am using
| Slide 4: System Requirement
The tutorials were recorded using the versions specified in previous slide
Subsequently the tutorials were edited to latest versions
To install latest system requirements go to Installation Sheet
|Slide 5: Prerequisites|| To practice this tutorial learner should have the knowledge of
| Slide 6:
Hagen-Poiseuille Flow Diagram
| Here is, Hagen-Poiseuille Flow diagram.
We can see the dimensions and boundaries of the pipe.
Viscosity of the fluid used, that is, water is given.
Pressure at the inlet is 20 Pascals and at the outlet it is 0 Pascals.
As it is an incompressible flow, only the pressure difference is of importance.
| Slide 7:
Formulas and Analytical Solution
Read aloud the given points
| Formulas and Analytical Solution:
For Hagen-Poiseuille flow, Pressure drop along the pipe is:
(P1 minus P2) equals (32 mu Uaverage L) upon (D square)
Uaverage into D upon nu, that comes out to be, 2080
|Slide 8: Solver|| Type of solver used here is icoFOAM.
It is used for incompressible, laminar flow of Newtonian fluid.
| Slide 9:
Pressure Boundary Conditions
| Pressure Boundary Conditions used,
| Slide 10:
Velocity Boundary Conditions
| Velocity Boundary Conditions used,
| Show 3dpipe folder.
Show the 3dpipe folder
| For executing this case, first let's create the case directory in the 'icoFoam' folder.
And give it some name.
I have named it as '3dpipe'.
|Point the mouse pointer from lid driven folder to 3d pipe folder.|| To know the location of this folder, go through the tutorial on lid driven cavity.
Copy this '0' (zero), 'constant' and 'system' folders of lid driven cavity problem in the newly created folder.
|Go inside the 3dpipe folder.||Let's go inside the '3dpipe' folder.|
|Hover the pointer over the folder inside the 3dpipe folder.||I have already copied the folders into my '3dpipe' folder and modified the files in it.|
|Go into the '0' folder and open P file and show it|| Now, let's go into the '0' folder and open the 'P' file.
This is the pressure boundary condition file.
|Show the pressure boundary condition file and show the dimensions inside it.||Note that the dimensions are in (meter square) per (second square) (m2/s2).|
|Show the pressure value written||Hence the pressure value in Pascals is divided by the density, that is, 1000 Kg/m3 (Kg per meter cube), and written here.|
|Close the file||Let's close the file.|
|Open U file in the same folder and show.|| File containing the velocity boundary condition is as seen.
Let's open the file we can see the velocity boundary condition for inlet, outlet and fixed walls.
|Close the file and come out of the '0' folder.||Let's close the file and come out of the '0' folder.|
|Switch back to the slides.||To see the blocking strategy, let me switch back to the slides.|
| Slide 11: Blocking Strategy
Hover the pointer on the geometry and drag it towards the z direction.
|To create a 3D geometry of a pipe I have made a 2D circular geometry and extruded the length in z direction.|
|Point out the numbering pattern.||Numbering pattern is as shown. We can also see the dimension of the mesh.|
|Minimize the slides||To see the blockMeshDict file, let's minimize the slides.|
|Go to folder 'constant' and then 'polyMesh' and open blockMeshDict file and show it.|| Let's go into the folder 'constant', and then 'polyMesh'.
Let's open theblockMeshDict ' file.
We can see the vertices, blocks,edges and boundaries for inlet, outlet and fixed walls.
|Close the file and come out of the folder 'polyMesh||Let's close the file and lets come out of the 'polyMesh' folder.|
|Open and show transportProperties file and point at the value viscosity value|| We see the 'transportProperties'file. Lets open the file.
|Close the file and come out of the 'constant' folder.||Let's close the file and come out of the folder constant.|
|Go into the system folder and open the controlDict file. Show it.|| Let's go into the 'system' folder.
Now, let's have a look at the 'controlDict' file.
|Show time step value|| The solution converges after 18 seconds therefore the final time step is kept 19.
|Close the file and the Home folder.|| Let's close the file.
Let's close the 'Home' folder.
|Press 'Control', 'Alt' and 'T' keys altogether.|| Now to execute the case, we will first go inside the '3dpipe' folder through terminal.
|Type run and press Enter in the terminal.||Type run and press Enter.|
|Type cd (space) tutorials and press Enter.||Type cd (space) tutorials and press Enter.|
|Type cd (space) incompressible and press Enter||Type cd (space) incompressible and press Enter.|
|Type cd (space) icoFoam and press Enter||Type cd (space) icoFoam and press Enter.|
|Type cd (space) 3dpipe and press Enter||Type cd (space) 3dpipe and press Enter.|
|Type blockMesh and press Enter|| Now to create the mesh, type blockMesh and press Enter.
Meshing has been done.
|After the meshing is done, type icoFoam to start the iterations|| To start the iterations type icoFoam and press Enter .
We see the iterations are running.
|After the iterations are done, type paraFoam for postprocessing the results and press Enter.|| Iterations has been done.
After the iterations end, type paraFoam for postprocessing the results and press Enter.
|Click on Apply.||Let's click on Apply on the left hand side of the Object inspector menu to see the geometry.|
|Rotate the geometry by pressing the button of the mouse and move it in the required direction.||Let's rotate the geometry for a better view.|
|Click on the active variable control menu and select U in the drop-down menu||Click on the active variable control menu and select U in the drop-down menu.|
|Click on play button||At the top, in VCR toolbar, click on Play button.|
|Go to Object Inspector menu, go to Display, click on Rescale data range||Go to Object Inspector menu, go to Display, click on Rescale to data range.|
|go to the toolbar named common, click on Clips and press Apply|| To view the half section, go to the toolbar named common, click on Clips.
Go to Object Inspector menu properties and press Apply.
Let's zoom in.
|Open the color legend||Let's open the color legend.|
|We can see the maximum velocity is near to the actual maximum velocitythat is 0.40 meters per second.|
|Go to Filters> Data Analysis> Plot Over Lines||To view the graph go to Filters at the top, Data Analysis and press Plot Over Line.|
|Click on Y axis and press Apply||Press Y axis and press Apply.|
|Point towards the parabolic profile||We can see the parabolic profile for Hagen-Poiseuille flow.|
|Close the graph||Let's close the graph.|
|Close ParaView||Let's close ParaView.|
|Switch to the slides||And switch to the slides.|
|Slide 12: Summary|| In this tutorial we have learnt:
| Slide 13 : Assignment
|| As an assignment,
Change the geometry parameters such as length and diameter
Change the corresponding pressure ratio and
Use the fluid of different viscosity
|Slide 14: About Spoken tutorials||
|Slide 15: About Spoken tutorials|| The Spoken Tutorial Project Team
| Slide 16: Forum to answer questions
| Slide 17: Forum to answer questions
| Slide 18: Lab Migration project
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|Slide 20: Acknowledgement|| Spoken Tutorial Project is a part of the Talk to a Teacher project