[hhh]

Dear foamers,
i am doing analysis under water vechile,i just design in catia,please give idea how i start with this one it has rectangular box six padles(left side 3 and right side 3) to flap in under water.please give me idea with basic how i start with preprocessing(mesh) and solver.please find my attached design.


Regards,
hhh
kumar

[Sachin m]

Originally Posted by lillberg

Hi,

I've been working with underwater and free surface hydrodynamics using FOAM and now OF since 1999 computing several benchmark cases including Wigley hulls, DTMB 5415, DARPA Suboffs etc using LES and VOF implementations. Most of the work is published or found in conference procedings. If you're interested please send me an email and I'll send copies of the papers.

Regards

/Eric

Hi Eric ,

Iam sending this email in regard to your post on 'CFD ONLINE' relating to benchmark cases of several hulls using LES and VOF. I am a Mtech student and my project is related to the hydrodynamics of vessel. I would like to know more about ship hydrodynamics in OPEN Foam and in particular the wigley hulls using VOF method. Please help me out by sending a copy of this particular case.

[fondexx]

hi partners

I'm trying to make a CFD analysis of the KCS hull using interFoam, butn I can't find the convergence and when I see the results on para Foam I can see some interference or something, can you help me?

[Sachin m]

Hi all,

I have run a drag force analysis of accustom hull using LTSInterFoam.
But after 12000 runs the free surface is seen above the ship hull. What could be the possible reason. Could it be because the solution is not yet stable. Should I run this for more number of iterations?

One more thing, I need to find the drag force on the hull. The function to write the force that I have asks for only one density value. How can that function give me the drag when it is a multiphase problem. There should be two values of density changing with the value of alpha1. Can anybody help me with this?

Below I am attaching few results:

1) The meshed hull with value of alpha1 shown. Blue region is air; red region is water.
2) Free surface after 100 iterations
3) free surface after 12000 iterations.

[Sachin m]

Has anyone tried the propeller tutorial in openFoam??
If yes let me know how to go about it.
My allrun file is not working. So iam trying to run it manually.
Can anyone help me out with the steps???

Thanks in advance.

[vava10]

Hey,

I working on ship simulation using OpenFOAM. This is my first project using openFoam.

I tried to capture the interface as follows as per one of the papers which I read

1.Creating a background mesh with blockMesh. blockMesh

2.Using snappyHexMesh to insert geometry, refine around geometry and other regions of interest by isotropic splitting of cells in all three dimensions. snappyHexMesh with castellatedMeshControls true and others false
3.Selecting the free surface region by using topoSet utility. topoSet
4.Refining mesh, based on the cells selected in topoSet, in vertical direction only using the refineMesh utility. refineMEsh
5.Snapping the mesh to the geometry surface and adding layers with snappyHexMesh. snappyHexMesh with castellatedMeshControls false and others true

But I get the following error while running this case in HPC

cell 3773907 of level 0 uses more than 8 points of equal or lower level

from the forum I got why the error comes (SnappyHexMesh problems)

My geometry is a kayak whose width is 0.41m and dept 0.29. I used a 0.55 refinement zone(depth) for the water surface capture because if I go below the valoe of 0.2 for the refinement zone the refinement zone is not visible beyond the refinement box for the ship

Is there any other options to capture the interface?

Can you please help me

Thanks in advance

[vava10]

Sorry. I accidentally posted here. This was supposed to be under another thread

But if anyone can help, I would appreciate it

[vava10]

Hey,

I working on ship simulation using OpenFOAM. This is my first project using openFoam.

I tried to capture the interface as follows as per one of the papers which I read

1.Creating a background mesh with blockMesh. blockMesh

2.Using snappyHexMesh to insert geometry, refine around geometry and other regions of interest by isotropic splitting of cells in all three dimensions. snappyHexMesh with castellatedMeshControls true and others false
3.Selecting the free surface region by using topoSet utility. topoSet
4.Refining mesh, based on the cells selected in topoSet, in vertical direction only using the refineMesh utility. refineMEsh
5.Snapping the mesh to the geometry surface and adding layers with snappyHexMesh. snappyHexMesh with castellatedMeshControls false and others true

But I get the following error while running this case in HPC

cell 3773907 of level 0 uses more than 8 points of equal or lower level

from the forum I got why the error comes (SnappyHexMesh problems)

My geometry is a kayak whose width is 0.41m and dept 0.29. I used a 0.55 refinement zone(depth) for the water surface capture because if I go below the valoe of 0.2 for the refinement zone the refinement zone is not visible beyond the refinement box for the ship

Is there any other options to capture the interface?

Can you please help me

Thanks in advance