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ShFlow January 11, 2009 23:10

the boundary condition mark
in the "boundaries" tab, it seems that the boundary condition mark(such as "S" for symmetry, "W" for wall "WL" for wave etc.) will only show on side which begin from 0, for example, if the mesh block in X direction is from 0 to 10, the BC mark is right on the side which x min=0,and x max=10. But if the mesh block in X dir is from 10 to 20,the BC mark is still on the side whick X min=0,X max=10,so the BC mark now isn't on the mesh boundary, how can I do to modify these?

Jim Higgs January 11, 2009 23:23

Re: the boundary condition mark
It sounds like a display problem only. Look at the prepin file and check bcdata there (under file - edit simulation). Perhaps closing the GUI and reopening it or switching tabs and going back will fix it.

ShFlow January 12, 2009 00:03

Re: the boundary condition mark
The following is the input file, I try to edit it and reopen, but seems no use...

Title This is a sample input file


remark='units are ...',



ifin=2, gz=0.,

iedt=2, pltafrc=0.01,


gy=10., /

&limits /



rhofs=917., thexf1=0.00018, cv1=4182., cvs1=2100.,

pofl1=0., thc1=0.597, thcs1=2.215, clht1=3.35e+05,

ts1=273., tl1=273., tniyam=-1., tsdrg=1.,

mu1=0.001, muc00=0., muc0=1., muc1=0.,

muc2=0., muc3=0., mutmp1=0., mutmp2=0.,

mutmp3=1., muthk=0., muthn0=0., muthn1=0.,

cangle=90., sigma=0.073, csigma=0., rf2=2.87e+06,

tmelt=0., teut=0., ceut=0., cexf1=0.,

cstar=0., dratio=0., pcoef=0., fluid1='Water at 20 C',

units='SI', /

&scalar /




vbct(1,4)=-2., /


nxcelt=40, px(1)=700., px(2)=710.,

nycelt=20, py(1)=695., py(2)=705.,

nzcelt=8, pz(1)=0.0, pz(2)=4.,


&obs /

&fl /

&bf /

&temp /

&motn /



anmtyp(2)='vel', anmtyp(3)='part',

anmtyp(4)='vort', /





rsxmin=700, rsxmax=704, rsymin=690, rsymax=700,

rszmin=0, rszmax=4, rscsize=1, / &HEADER


&parts /

Documentation: general comments, background, expectations, etc.

Jim Higgs January 12, 2009 00:26

Re: the boundary condition mark
&bcdata ubct(1,2)=-2., wbk=6, vbct(1,4)=-2., /

This defines the back boundary, Y max, as a velocity boundary. Perhaps you do not have proper write permissions for the prepin file. Close Flow-3D gui and try editing the prepin file with a text editor like notepad, and insert wl=6, to make X min a velocity boundary. If you cannot save the change, then you probably do not have write privileges and should contact your computer support department. You could also try editing the file in a different directory. Just a guess.

&bcdata ubct(1,2)=-2., wbk=6,wl=6, vbct(1,4)=-2., /

ShFlow January 12, 2009 01:46

Re: the boundary condition mark
May I send the input file to you ?

Jim Higgs January 12, 2009 12:53

Re: the boundary condition mark
ShFlow, I brought in and then typed in the same mesh information you are using, and duplicated the problem. It appears to only be a display/GUI problem. If the text in the editor is correct, then the simulation should run fine.


wr=6, wbk=6, ubct(1,2)=-2, vbct(1,4)=-2, /


nxcelt=40, px(1)=700.,px(2)=710.,

nycelt=20, py(1)=695., py(2)=705.,

nzcelt=8, pz(1)=0.0, pz(2)=4., /


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