I want to simulate a Wave in the flume

mfeizbahr · January 2, 2011, 08:01

I want to simulate a Wave in the flume..
how should I define boundary conditions ?
I mean in which direction should I define Flow?

MuxaB · January 17, 2011, 02:39

wave are always defined at the x or y mesh boundaries, i.e., vertical boundaries. Designate a mesh boundary a wave boundary, set the initial fluid volume in the domain using fluid height, use the same height at the wave boundary, set the wave length and amplitude - and you are good to go.

mfeizbahr · January 17, 2011, 05:27

Tnx a lot for help..
but.. what do u mean by : " wave are always defined at the x or y mesh boundaries .. "
you mean there is no mesh need for Z direction ?

MuxaB · January 19, 2011, 01:45

Quote:

Originally Posted by mfeizbahr

Tnx a lot for help..
but.. what do u mean by : " wave are always defined at the x or y mesh boundaries .. "
you mean there is no mesh need for Z direction ?

No, mesh should be defined in all three directions. What I meant is that in FLOW-3D surface wave generators are implemented as mesh boundary conditions and can be applied at any of the four mesh boundaries, xmin, xmax, ymin or ymax.

mfeizbahr · January 19, 2011, 06:20

thank you for informations.

fortunately after all I simulated the wave but there is another problem I faced, is the water dept decrease gradually .
I chose X min ( LW ) but really i don't know what should I choose for X max ?
in case of " continuative " the water dept decreased gradually.
in case of " Symmetry " water turn back after it reach to the end of mesh.

can u help me with that ?
i need no decrease in water dept and continuant wave for example like a seaside.

stefmascio · January 19, 2011, 10:38

choose the "Outflow" b.c. with the option "Allow fluid to enter...".

mfeizbahr · January 20, 2011, 04:55

thank you Stefmascio...

but there is still dept decreasing..

mfeizbahr · January 22, 2011, 00:50

Dear Stefmascio...

When I did your suggestion for choosing the "Allow fluid to enter...” after running simulation the water dept start decreasing gradually and suddenly after 20 sec, new stream started coming into the flume with reverse direction, interfacing the waves and the incoming fluid cause an overtopping the water depth…
so this suggestion might not be a proper solution....
do u have any other idea ?

bejewel · January 22, 2011, 21:43

Model Setup\ Numerics\Wave boundary conditioon
then to choose:
Eliminate net volume flux at wave boundary,or
Include net volume flux at wave boundary.

good luck!

mfeizbahr · January 23, 2011, 03:08

Dear Bejewel ...

there is no " wave boundary condition " in Numerics ....
and really I could not fined any of your suggestions there....

thank you any way

Ghirghidov · January 24, 2011, 05:58

Dear mahdi,

Try to change mesh resolution.

Regards.

bejewel · January 25, 2011, 11:04

Flow-3D 9.4---> " wave boundary condition " in Numerics

January 2, 2011, 08:01	I want to simulate a Wave in the flume	#1
mfeizbahr New Member mahdi Join Date: Jan 2011 Posts: 8 Rep Power: 15	I want to simulate a Wave in the flume.. how should I define boundary conditions ? I mean in which direction should I define Flow?

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Outlet boundary condition for wave flume with interFoam solver	Arnoldinho	OpenFOAM	9	July 10, 2018 06:15
How to simulate a sea wave striking a ship antenna	Freeman	FLUENT	0	February 25, 2009 15:17
to simulate shock wave propagation with turbulence	cfdgeek	Main CFD Forum	1	August 31, 2008 17:47
simulate propagating wave	Gian, S.	Main CFD Forum	0	October 27, 2006 04:11
how to simulate wave?	dingding	CFX	3	July 18, 2001 12:20

January 17, 2011, 02:39		#2
MuxaB Senior Member michael barkhudarov Join Date: Mar 2009 Location: Sante Fe, New Mexico, USA Posts: 337 Rep Power: 18	wave are always defined at the x or y mesh boundaries, i.e., vertical boundaries. Designate a mesh boundary a wave boundary, set the initial fluid volume in the domain using fluid height, use the same height at the wave boundary, set the wave length and amplitude - and you are good to go.

January 17, 2011, 05:27		#3
mfeizbahr New Member mahdi Join Date: Jan 2011 Posts: 8 Rep Power: 15	Tnx a lot for help.. but.. what do u mean by : " wave are always defined at the x or y mesh boundaries .. " you mean there is no mesh need for Z direction ?

January 19, 2011, 06:20		#5
mfeizbahr New Member mahdi Join Date: Jan 2011 Posts: 8 Rep Power: 15	thank you for informations. fortunately after all I simulated the wave but there is another problem I faced, is the water dept decrease gradually . I chose X min ( LW ) but really i don't know what should I choose for X max ? in case of " continuative " the water dept decreased gradually. in case of " Symmetry " water turn back after it reach to the end of mesh. can u help me with that ? i need no decrease in water dept and continuant wave for example like a seaside.

January 19, 2011, 10:38		#6
stefmascio Member Stefano Join Date: Mar 2009 Posts: 59 Rep Power: 17	choose the "Outflow" b.c. with the option "Allow fluid to enter...".

January 20, 2011, 04:55		#7
mfeizbahr New Member mahdi Join Date: Jan 2011 Posts: 8 Rep Power: 15	thank you Stefmascio... but there is still dept decreasing..

January 22, 2011, 00:50		#8
mfeizbahr New Member mahdi Join Date: Jan 2011 Posts: 8 Rep Power: 15	Dear Stefmascio... When I did your suggestion for choosing the "Allow fluid to enter...” after running simulation the water dept start decreasing gradually and suddenly after 20 sec, new stream started coming into the flume with reverse direction, interfacing the waves and the incoming fluid cause an overtopping the water depth… so this suggestion might not be a proper solution.... do u have any other idea ?

January 22, 2011, 21:43		#9
bejewel New Member bejewel Join Date: Jan 2011 Posts: 3 Rep Power: 15	Model Setup\ Numerics\Wave boundary conditioon then to choose: Eliminate net volume flux at wave boundary,or Include net volume flux at wave boundary. good luck!

January 23, 2011, 03:08		#10
mfeizbahr New Member mahdi Join Date: Jan 2011 Posts: 8 Rep Power: 15	Dear Bejewel ... there is no " wave boundary condition " in Numerics .... and really I could not fined any of your suggestions there.... thank you any way

January 24, 2011, 05:58		#11
Ghirghidov Member Armen A. Ghirghidov Join Date: Mar 2009 Posts: 50 Rep Power: 17	Dear mahdi, Try to change mesh resolution. Regards.

January 25, 2011, 11:04		#12
bejewel New Member bejewel Join Date: Jan 2011 Posts: 3 Rep Power: 15	Flow-3D 9.4---> " wave boundary condition " in Numerics