pressure boundary

fang · May 27, 2009, 23:46

Does pessure boundary mean new fluid flows into the computional domain under the influence of pressure?

melissa · June 1, 2009, 11:01

Hi~
The fluid fraction determines what fluid is entering. If you have a tank with fluid and void and you set the top boundary to pressure and leave the fluid fraction to 1 then fluid 1 will enter the tank. If you set the fluid fraction to zero and a pressure boundary then the void will use that pressure and no fluid will enter the domain. However if you are using two-fluid then then having fluid fraction as 0 will allow fluid 2 to enter the domain. So fluid fraction of 1 for fluid 1 and fluid fraction 0 for void/fluid2.

MC

fang · June 3, 2009, 21:03

Thank you,melissa!
I understand.

nikesandman · October 20, 2009, 01:38

Hi Melissa,

Would this mean that for a casting simulation you would want to include some void region (considering that the shot sleeve is not completely full of material)?

MuxaB · October 21, 2009, 00:15

Nikesandman,

referring to your original post, you can include the shot sleeve in your simulation to replace the inlet boundary. The plunger can have a time-dependent velocity just like in the real machine.

May 27, 2009, 23:46	pressure boundary	#1
fang New Member linfangcai Join Date: May 2009 Posts: 9 Rep Power: 16	Does pessure boundary mean new fluid flows into the computional domain under the influence of pressure?

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June 1, 2009, 11:01		#2
melissa Member MC Join Date: Mar 2009 Posts: 56 Rep Power: 17	Hi~ The fluid fraction determines what fluid is entering. If you have a tank with fluid and void and you set the top boundary to pressure and leave the fluid fraction to 1 then fluid 1 will enter the tank. If you set the fluid fraction to zero and a pressure boundary then the void will use that pressure and no fluid will enter the domain. However if you are using two-fluid then then having fluid fraction as 0 will allow fluid 2 to enter the domain. So fluid fraction of 1 for fluid 1 and fluid fraction 0 for void/fluid2. MC

June 3, 2009, 21:03		#3
fang New Member linfangcai Join Date: May 2009 Posts: 9 Rep Power: 16	Thank you,melissa! I understand.

October 20, 2009, 01:38		#4
nikesandman New Member Sean Join Date: Oct 2009 Posts: 3 Rep Power: 16	Hi Melissa, Would this mean that for a casting simulation you would want to include some void region (considering that the shot sleeve is not completely full of material)?

October 21, 2009, 00:15		#5
MuxaB Senior Member michael barkhudarov Join Date: Mar 2009 Location: Sante Fe, New Mexico, USA Posts: 336 Rep Power: 18	Nikesandman, referring to your original post, you can include the shot sleeve in your simulation to replace the inlet boundary. The plunger can have a time-dependent velocity just like in the real machine.