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- - Wave Tank (https://www.cfd-online.com/Forums/openfoam-solving/57882-wave-tank.html)

The results are the same with buoyantPressure on the faces parallel to z axis (the same axis where g is defined) :(

Floating point exception : first order wave

I have corrected the boundary condition according to generate a 1st order wave but i obtain a floating point exception

This is the case

http://dl.dropbox.com/u/3617688/groo...Version.tar.gz

SOLVED: it was a bad BC on U on atmosphere patch

Hi nuovodna,

The link seems to be broken, can you re-post it please?

best regards,

Yann

http://db.tt/SaIRb6

It seems no working : prediction of analytical solution is wrong :(

Quote:

Originally Posted by lostin4ever (Post 234661)

Hi all,

I have simulated tank3dsloshing using interDymfoam. For having a clear picture of comparison of theoretical and simulation results I am using natural mode frequency of tank. As far as surface mode are concern I am getting very perfect match with theoretical result for lower frequencies.

But in case of tank3d sloshing there should be mode in both the direction ( direction along which table is vibrating(width) and along length. In the simulations results along the width are perfectly ok but there is no mode shape along the length of the tank ( I have done the experiment on vibration shake table and the modes were there. ) Can anyone tell how I can correct this? Another thing is the amplitude are not as high as they should in resonance case.

For 3D tank the mode frequency is calculated by
mode frequency f is calculated as..
omega = 2*pi*f
omega = sqrt (gktanh(kh))
k = pi*sqrt((2m/W)^2+(2n/L)^2)
m and n are the natural mode along the width and length.
h is water level height in tank . in my case it is 6cm.

problem specifications :
Rectangular tank 35X50X40 cm
translation vibration for table given along 50 cm length
freq. is applied corresponding 3 mode along 50cm and 3rd mode along 35 cm ..
m =3 and n=3 in above equation.

I will send the files and simulation video if someone want to see. Here i am not able to share those due to size limit of forum.

Thanks

:)

hi lostin4ever
i have also run same case as yours, but unable to run it. can you help in this problem

Any help would be appreciated:

I am using FLUENT to model a regular wave tank with linear theory and dynamic mesh. I am using a VOF multiphase model (water and air), with transitory regime. The length of the water tank is 200m, from th mobile wall, with 16 m depth. I want to measure the magnitude (amplitude) of the wave at at position x = 20 m from the mobile wall, through of the time, in the free surface (depth= 0m), . How to measure the magnitude (amplitude) in that distance?.

Hi Pedro,

You have stumbled into the OpenFoam part of the forum, so I guess that we might not be able to helping you. You will probably get at lot more help, if you pose the same question in an appropriate thread.

Kind regards,

Niels

Hi Niels

I have tried in several threads and I posted here too because It`s a topic related.

Best regards,

Pedro

Hello Eugene,

On a completely unrelated note, could you tell me how you have embedded those files in one of your first posts on this forum?

Thanks,
Sagun