Mass consertative boundary condition

harsha_kulkarni · March 19, 2016, 05:59

Hello Foamers,
Is their any Derived bounary condition for inlet which conserve the mass in side the domain.

Regards
Harshawardhan

avila.vc · March 19, 2016, 15:11

Hi, I'm no expert, but as far as I know, once the simulation is stable and stationary, the mass balance should be respected.

If you want to check it, just compute the mass inlet and oulet flows.

harsha_kulkarni · March 20, 2016, 00:05

this is for continuous process..not for not for semi-batch proess...we should keep mass inside the domain constant

avila.vc · March 20, 2016, 00:36

Ok, so it is just like I said. dm/dt=mass.in - mass.out, you may set inlet mass rate and outlet pressure, for exemple, it depends on your case. When it converges, dm/dt=0. So mass is kept constant in the domain.

harsha_kulkarni · March 20, 2016, 00:45

yes, and for kepping mass constant inside the domain we should give inlet velocity or inlet flux as a boundary condition

March 19, 2016, 05:59	Mass consertative boundary condition	#1
harsha_kulkarni Senior Member harshawardhank Join Date: Mar 2014 Posts: 209 Rep Power: 13	Hello Foamers, Is their any Derived bounary condition for inlet which conserve the mass in side the domain. Regards Harshawardhan

March 19, 2016, 15:11		#2
avila.vc Member Vinícius da Costa Ávila Join Date: Jul 2015 Location: Porto Alegre, Brazil Posts: 62 Rep Power: 10	Hi, I'm no expert, but as far as I know, once the simulation is stable and stationary, the mass balance should be respected. If you want to check it, just compute the mass inlet and oulet flows. __________________ Vinícius dC.A.

March 20, 2016, 00:36		#4
avila.vc Member Vinícius da Costa Ávila Join Date: Jul 2015 Location: Porto Alegre, Brazil Posts: 62 Rep Power: 10	Ok, so it is just like I said. dm/dt=mass.in - mass.out, you may set inlet mass rate and outlet pressure, for exemple, it depends on your case. When it converges, dm/dt=0. So mass is kept constant in the domain. __________________ Vinícius dC.A.

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March 20, 2016, 00:05		#3
harsha_kulkarni Senior Member harshawardhank Join Date: Mar 2014 Posts: 209 Rep Power: 13	this is for continuous process..not for not for semi-batch proess...we should keep mass inside the domain constant

March 20, 2016, 00:45		#5
harsha_kulkarni Senior Member harshawardhank Join Date: Mar 2014 Posts: 209 Rep Power: 13	yes, and for kepping mass constant inside the domain we should give inlet velocity or inlet flux as a boundary condition