[Jackie Chen]

hello!I am a freshie and is trying to use OpenFOAM to simulate scour around monopile structure. I tried a few times by using the solver "InterFoam", I cannot get what I want. The scour process is complicated. May anyone help me and tell me how to figure it out. Thanks a billion.

[Jackie Chen]

ANyone can Help?

[ngj]

Hi Chen,

Yes, the scour process is not straight forward to simulate, however, you must elaborate on what type of approach you want to take, before anyone can provide you with a helpful answer.

E.g. what did you want to achieve by using interFoam?

Do you want to use e.g. two phase simulations, where the phases are sediment and water?

Or do you rather want to solve the sediment as a passive agent in the water?

Do you need to resolve the water surface?

Etc, etc, etc. Once you have elaborated on these topics, we might be able to help a bit.

Kind regards,

Niels

[Jackie Chen]

Originally Posted by ngj

Hi Chen,

Yes, the scour process is not straight forward to simulate, however, you must elaborate on what type of approach you want to take, before anyone can provide you with a helpful answer.

E.g. what did you want to achieve by using interFoam?

Do you want to use e.g. two phase simulations, where the phases are sediment and water?

Or do you rather want to solve the sediment as a passive agent in the water?

Do you need to resolve the water surface?

Etc, etc, etc. Once you have elaborated on these topics, we might be able to help a bit.

Kind regards,

Niels

Niels

Thanks for your kind reply.
I am a freshie. I want to investigate the scour depth around pile through using either Openfoam or Fluent. If using Opeanfoam the solver used should be interFoam. Two phase simulation is applicable. Some papers by descriped such process but is not so clear to me. May you provide me something like a guideline? Then i can follow your instruction.Now i Am confusing about what to do for my future work!Or you have any example to show me?

Thanks
Regards
Chen Long

[ngj]

Dear Chen,

One of the most essential questions in this context is the following:

How much time do you have for the project?

The reason I am asking is that to my knowledge, nobody has a made a sediment transport and bed response model available within OpenFoam. This means that you have to start coding everything from the bottom up, and if you are new to OpenFoam this will take a substantial amount of time.

Two phase flows with buoyancy effects (e.g. water and sediment grains) are present in OpenFoam within settlingFoam (correct me if I am wrong!). I have never used it, so I will not be able to guide you in this regard. I do know, however, that the sediment bed is considered as a fluid, which requires quite a few modifications, before you can model scour processes.

interFoam cannot be used for this type of work, simply because you are after a mixing process of sediment and water, whereas interFoam are targeted at maintaining a very sharp interface between the two phases.

Kind regards,

Niels

[Jackie Chen]

Originally Posted by ngj

Dear Chen,

One of the most essential questions in this context is the following:

How much time do you have for the project?

The reason I am asking is that to my knowledge, nobody has a made a sediment transport and bed response model available within OpenFoam. This means that you have to start coding everything from the bottom up, and if you are new to OpenFoam this will take a substantial amount of time.

Two phase flows with buoyancy effects (e.g. water and sediment grains) are present in OpenFoam within settlingFoam (correct me if I am wrong!). I have never used it, so I will not be able to guide you in this regard. I do know, however, that the sediment bed is considered as a fluid, which requires quite a few modifications, before you can model scour processes.

interFoam cannot be used for this type of work, simply because you are after a mixing process of sediment and water, whereas interFoam are targeted at maintaining a very sharp interface between the two phases.

Kind regards,

Niels

Niels

Thanks again! I will take into account your considerations!

Investigate Scour with Openfoam is not new.

A company named Edenvale Young (http://www.edenvaleyoung.com/bridge_scour.php) is using interFoam to study scour around bridge pier.

Xiao Feng Liu is another expert using Openfoam for sdiemnt transport. A few paper described such efforts. if you are interested you can search online.

Thanks for your help again

Regards
Chen Long

[ngj]

Hi Chen,

I agree that it is not new to use OpenFoam for scour processes. What I meant was that nobody seem to have made their method freely available/open-source. Therefore, you will need to do the majority of the implementations yourself.

You could also look for Arne Stahlmann's contribution at ICCE (http://journals.tdl.org/icce/index.p...w/6655/pdf_635) and my own work for free morphodynamic modelling (http://orbit.dtu.dk/en/publications/...b7ff01%29.html).

Kind regards,

Niels

[Jackie Chen]

Originally Posted by ngj

Hi Chen,

I agree that it is not new to use OpenFoam for scour processes. What I meant was that nobody seem to have made their method freely available/open-source. Therefore, you will need to do the majority of the implementations yourself.

You could also look for Arne Stahlmann's contribution at ICCE (http://journals.tdl.org/icce/index.p...w/6655/pdf_635) and my own work for free morphodynamic modelling (http://orbit.dtu.dk/en/publications/...b7ff01%29.html).

Kind regards,

Niels

Hi Niels

Thank you very much for the info. Your work could be a huge hand for my work.

Regards
Chen Long

[santiagomarquezd]

Hi Jackie, the Patricio Bohorquez's solver is what you need. Please check his PhD. thesis.

Regards.

[kingle]

Hi, Chen!
I'm studying this problem by OpemFOAM, but I know the key technique is "dynamic mesh", I read some papers , but i still don't konw how to realize it. Good luck to both you and me!

[sophie_l]

Hi,

I am working on similar topics as well. It's great to know you guys. How's your work going?

best,
Sophie

[Jackie Chen]

Hi, Sophie

No significant progress, still working on it, how abt you?

[sophie_l]

Hi Long,

I found a solver called solidParticleFoam, and I am trying to figure out how to generate the input file 'positions' using OF code. Still stuck here. Have you decided what approach to simulate scour process yet?

best,
Sophie

[Jackie Chen]

Hi Sophie

Most probably will use interFoam/interDyMFoam, solidPaticleFoam is a new solver? How about the computational demanding when using this solver?

[sophie_l]

It's not a new solver. Please check this page, http://openfoamwiki.net/index.php/Co...idParticleFoam . Maybe it is helpful to you as well. About interFoam/interDyMFoam, have you started to modify the code to work for you?

[Jackie Chen]

SO u try to modify this solidparticleFoam to study the scour process? I am mainly focus on the flow field at this stage, havent modify the interfoam solver, i will try to study the solidaparticleFoam, keep in touch.

[kingle]

Originally Posted by sophie_l

It's not a new solver. Please check this page, http://openfoamwiki.net/index.php/Co...idParticleFoam . Maybe it is helpful to you as well. About interFoam/interDyMFoam, have you started to modify the code to work for you?

I am a friend of chen, now i want to use automesh method to simulate deformation of riverbed, i know some reserches on two phase flow,but i think the interface between water and morphology is sharp, so the Exner-equation should be a choice, the FAM(finite area method) is also applied in some thesis. solidParticleFoam is to solve the mixture of sediment and water,but what i focus is the riverbed deformation, and not the content of sediment in the water(i recommend u to read Xiaofeng Liu's thesis).
thanks, looking for your reply!
kingle

[sophie_l]

Hi Kingle,

Thanks for your suggestion. I think Liu's thesis is very helpful.

solidParticleFoam is not ideal as it's mainly for demonstration purpose, but I think it's worth looking at as a tutorial. I am focused on the sediment transport at the moment, and haven't started looking at bed deformation, but I am very interested in your ideas. How's it going with your automesh method?

Cheers,
Sophie

[kingle]

Originally Posted by sophie_l

Hi Kingle,

Thanks for your suggestion. I think Liu's thesis is very helpful.

solidParticleFoam is not ideal as it's mainly for demonstration purpose, but I think it's worth looking at as a tutorial. I am focused on the sediment transport at the moment, and haven't started looking at bed deformation, but I am very interested in your ideas. How's it going with your automesh method?

Cheers,
Sophie

I just understand the main idea about the method of mesh deformation，which the boundary（bottom）move at the velocity in a time step acoording the Exner equation. but, you konw, it need a good knowledge of C++ and some other technics, so I haven't implented based OpenFOAM, i have strugled on this problem for a long time, do you have interest? Both or us can communicate with each other and settle this problem. I know some people try to the method of Two-phase which often used in scour of pipeline on the seabed. Some other people use FAM to simulate the sediment transport. you know some software ,such as FLUENT, can also simulate the morphology by dynamic mesh using UDF, and it's theory is based on sediment continuty(Exner equation) which is more understandable.
Looking for your reply.

[sophie_l]

Hi,

I am interested in your study, however I haven't looked into mesh deformation yet. Have you tried interDyMFoam? Would it be useful to you?

Cheers,
Sophie