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Amirhossein Arzani
Приєднався 13 лис 2010
Computational Biomechanics Group at the University of Utah:
bio.mech.utah.edu/
bio.mech.utah.edu/
Advanced CFD & FEM (Lecture 14: Error estimation)
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previously developed by me.
The course is motivated by the open-source FEM solver FEniCS and is intended to fill the theoretical gap needed to use FEniCS (e.g., weak forms and other theoretical concepts necessary to better use FEniCS for CFD).
For tutorial series on FEniCS, including CFD examples see Python for Scientific Computing (Py4SciComp):
github.com/amir-cardiolab/Py4SciComp
Lecture 14:
Order of accuracy in FEM, error estimation.
The course is motivated by the open-source FEM solver FEniCS and is intended to fill the theoretical gap needed to use FEniCS (e.g., weak forms and other theoretical concepts necessary to better use FEniCS for CFD).
For tutorial series on FEniCS, including CFD examples see Python for Scientific Computing (Py4SciComp):
github.com/amir-cardiolab/Py4SciComp
Lecture 14:
Order of accuracy in FEM, error estimation.
Переглядів: 519
Відео
Advanced CFD & FEM (Lecture 13: Linear and nonlinear solvers)
Переглядів 1626 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 12: Boundary conditions and best practices)
Переглядів 1266 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 11: Fractional steps approaches for Navier-Stokes)
Переглядів 1376 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 10: Coupled u-p approach for Navier-Stokes)
Переглядів 1026 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 9: Navier-Stokes, Pressure Poisson, and Vorticity equations)
Переглядів 1396 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 8: Stokes equation)
Переглядів 926 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 7: Unsteady advection-diffusion equation)
Переглядів 886 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 6: SUPG stabilization for the advection-diffusion equation)
Переглядів 1716 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 5: 3D advection-diffusion)
Переглядів 1416 місяців тому
dvanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previous...
Title: Advanced CFD & FEM (Lecture 4: 1D advection-diffusion)
Переглядів 1416 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 3: FEM discretization)
Переглядів 2216 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 2: Weak forms in FEM)
Переглядів 3316 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Advanced CFD & FEM (Lecture 1: Intro to course + Mathematical preliminaries)
Переглядів 1,5 тис.6 місяців тому
Advanced computational fluid dynamics (CFD) and finite element method (FEM) course: This is an advanced FEM-based CFD course. The course is suitable for those already familiar with the basics of CFD who would like to learn how FEM is used in CFD. The lectures are short since they are recorded with already written lecture notes, but the content is based on a semester-long graduate course previou...
Neural networks that think!: Extrapolating and interpreting in scientific deep learning
Переглядів 534Рік тому
This is a presentation at the 2023 USNCCM conference. Motivated by how humans think when we want to extrapolate our knowledge, we proposed a similar strategy for neural networks to improve extrapolation. We did this through a flexible XAI (interpretable and explainable AI) approach that can be either post-hoc and by-design. Abstract: Towards Interpretable and Generalizable Deep Learning in Mech...
ParaView's calculator for data post-processing
Переглядів 3,4 тис.Рік тому
ParaView's calculator for data post-processing
Introduction to ParaView and its various useful filters for data visualization/processing.
Переглядів 1,3 тис.Рік тому
Introduction to ParaView and its various useful filters for data visualization/processing.
Processing particle data with VTK (for Lagrangian particle tracking)
Переглядів 1,1 тис.Рік тому
Processing particle data with VTK (for Lagrangian particle tracking)
Wall shear stress divergence with VTK (and note on WSS topology).
Переглядів 596Рік тому
Wall shear stress divergence with VTK (and note on WSS topology).
Interpolate unstructured mesh data with VTK
Переглядів 1,4 тис.Рік тому
Interpolate unstructured mesh data with VTK
Vector data (gradient and curl) with VTK
Переглядів 1,1 тис.Рік тому
Vector data (gradient and curl) with VTK
Multi-fidelity and multi-physics modeling with PINN in PyTorch
Переглядів 888Рік тому
Multi-fidelity and multi-physics modeling with PINN in PyTorch
Physics-informed neural networks (PINN) with PyTorch
Переглядів 4,5 тис.Рік тому
Physics-informed neural networks (PINN) with PyTorch
Neural networks (mapping between 2D field variables, image to image) with PyTorch
Переглядів 458Рік тому
Neural networks (mapping between 2D field variables, image to image) with PyTorch
Biotransport (advection-diffusion-reaction) in FEniCS
Переглядів 434Рік тому
Biotransport (advection-diffusion-reaction) in FEniCS
Hi sir, I'm Naeem M Phil Mathematics, I studied courses FEM, CFD, can I have your contact number? Please. As I'd like to pursue my PhD using Numerical Techniques like FEM, FVM. I need guidance to secure my admission through funded scholarship
Hello, can I ask about the name of the program in which you write the code?؟؟
This is a Python code with VTK libraries. If you mean the text editor that was SubLime Text.
Very useful video. Thank you so much
لذت بردم از این انگلیسی روون و دانش عالی،باریکلا پسر،🎉🎉🎉❤❤❤❤
Thank you so much for this comprehensive introduction to ParaView. It saved my time.
Great Info
Thank you very much for this informative video. I do have a question. I used Paraview to apply a Tube filter on a tract (with one streamline) and saved the new thicker tract as Tube.vtk. But after converting Tube.vtk to a .trk file, I noticed the number of streamlines is zero and I am not able to visualize it in freeview. Do you have any idea about the possible cause? Thank you
I am not sure why there is a need to save the streamlines as a vtk file. Another option is to save state in paraview. This creates a small *.pvsm file that saves your paraview work (all filters you applied, your rendering, etc.). Then you load the pvsm under load state and all of your work/visualization (including the tube you created) will appear again next time you load it.
Hello! I am very intrigued by this class. There are not many videos that cover the use of fem in CFD, let alone full classes! However, starting this course a question emerges. Why should someone use FEM instead BEM or finite volumes/difference method? What are pros and cons? I think that this topics should be discussed in the introduction. If I missed them, please let me know where to find them, I am very interested!
Hi, great video. Could you explain if it is possible to get the time average of WSSdiv using paraview?
Yes apply the temporal statistics filter after you calculate WSSdiv
Thanks for the useful tutorial! Do you know if there is a way to limit the vtkPlane to a certain distance around the origin point? and then use it for clipping a specific part of the object.
In that case you have to use a Box for clipping instead of Plane.
Amazing work, is it possible to use this for 3D case?
Yes but with an easy extension of the 2D code.
Hello brother i have a project to do on fenics for my edcation but i am not expert and yet i still don't understand so much how it work i downloaded ubuntu on my windows then anaconda then fenics then jupyter and paraview and downloaded the mshr channel the geometry i need to draw 2 rectangular parallelepiped width 3mm,height 0.5mm and length 6 mm and they are in contact so it is like an assembly with 1mm height rectangular separed in half . Can you please help me ?
Hello! Thank you for your video that is helping a lot! Though, I still have an issue: when I try reading the array with .GetArray(fieldname) before going to numpy, it returns an empty data whereas in Paraview I can clearly see the cell arrays in the information page. I tried with two different vtu and vtp files. Thank you!
Thanks for the tutorial, Dr. Amir. So I tried the plot over line functionality for a .vtp file but couldn't get any plot. I also converted the file to a .ex2 file, however it didn't help. Have you had a similar situation?
If you have a vtp file then I assume it is a surface. When you do plot over line for a surface the line has to exactly lie on the surface and if it is a curved surface then that might not work.
@@mramirh1 hi yes, you are right. I've a plane 2d surface of SPH particles. The problem seems to be with a 2d cloud of SPH particles. This problem can be solved by using delaunay2D on the data points first and then using "plot over line" on the delaunay2D. Thanks so much, Dr. Amir.
Hi. Thanks for your video again. For your code, may I ask one more question? I added the surface integral terms dot(p*n, v)*ds-nu*dot(dot(n, nabla_grad(u)), v)*ds to F, which I think should not cause a different because of the Dirichlet boundary condition. However, it turns out that the Newton solver can't converge after I added these two terms. Do you have any ideas for this?
Two things. With ds you need to specify which boundary you are applying the surface integral ds(1), .. . Also, keep in mind in FEM, if you apply the Dirichlet BC on a boundary then the test function on that boundary should be zero so those integrals are zero and you cannot have them if you also have Dirichlet BC on the same face.
@@mramirh1How to specify which boundary to apply the surface integral?
@@changheyang9252 I can't remember if I explained in one of the tutorials (you can check them). If not, just google or look at FEniCS mannual/book.
@@mramirh1 Thanks!
Amazing! Thank you so much for this. Content like this is truly exceptional and hard to find. I'm currently facing difficulties in creating a custom 2D mesh, such as a sinusoidal channel. I would greatly appreciate any assistance or suggestions regarding available software for this task. Thank you once again for your invaluable efforts🙏.
Thanks! Gmsh is probably the best free software for that purpose.
Hi, thanks a lot for this wonderful video. Could you please tell me how you plotted the velocity you got at the end of the video?
Not sure if I fully understand the question. You simply load the xdmf file you get from FEniCS into ParaView and then change the variable to velocity as shown. If you are asking abut the 2D streamline part at the end, you have to use the surfaceLIC filter. I explain that in my ParaView videos if you check them out.
@@mramirh1Thanks a lot!
Hey, thank you for shearing this. I have a question - is it easily applicable for results from Ansys Fluent?
Yes if you save Ansys results in a certain format you can load it in paraview and then convert to VTK (I believe the mesh needs to be tetrahedral).
can you also add a velocity field, generated e.g. with Fenics, in which your particles can move like passive tracers?
The most interesting topic in CFD! 🙂
Hello, Thank you for quick tutorial on getting started. It is hard to come up with python videos with VTK. Definitely put me on right track. :)
Thank you for your video! Unfortunately the text is too small to read on my laptop screen. Please enlarge the text size for the next videos!
Will do. You should view these in HD mode.
hello, i am learning the dolfinx, can you explain in video tutorial, how import geometry from gmsh for dolfinx?
This is a great presentation about PINN model application. recently, I have been deeply interested in this model for the water flow simulation. then I felt big barriers for the input data construction for the model. Can I get tips for the input geometry data set like mesh generation for the CFD model? or any recommendation ?
Awesome video! Thank you
Dear Professor thank very much for share Code and video, Would mind tell what is the size of channel? I think channel size is whether nano or micro ?
It is all non-dimensional. The Reynolds number is reported in the paper.
@@mramirh1 I suppose behavior of fluid in nano or micro is diffrent form CM size! I am right !!!!
Arzhani, this is my second question. I am trying to implement your method to predict velocity and pressure fields in a spinning shaft which is partially filled with oil, and outlets exposed to air, from 10 experimental data points. In traditional CFD I use the multiphase method, with close BC/IC as experiment. Can I use PINN on a spinning shaft, with oil sloshing everywhere and multiphase flow. Can PINN be used to measure both air and oil velocity / pressure fields Please let me know. Thank you
If you have a well-posed problem (meaning you know all BCs and parameters) then traditional CFD method is much more robust and faster. PINN is good when you have some measurement data and some unknown parameters in the CFD model.
@@mramirh1 thank you 🙏
Hi Arzhani. Great presentation. My question 1) in which software did you code PINN 2) How did the python-pytorch code understand wall location
Pytorch. By using VTK libraries boundary mesh data in VTK format can be extracted. You can see the code here: github.com/amir-cardiolab/PINN-wss
@@mramirh1 thank you 👏
Has the effect of sensor locations been studied ?
great presentation!
We used the open-source FEniCS based CFD solver Oasis: github.com/mikaem/Oasis Right now we are working on more complex simulations accounting for turbulence using LES (supported in Oasis)
Nice ! share the code on github ! which version of NS are you using ? what are your initial conditions ? is it a published work or just a toy project ?
See my comment below. The movie was a toy project, but right now we are working on more advanced simulations and publication. You can follow our work here:www.cardiolab.nau.edu/
I was trying to do similar things with Fenics. Can you provide a source or the equations that you used to do this?
See my comment. The FEniCS source code is Oasis and is available on github.
@@mramirh1 Awesome Thanks