should one of the two outlets be 'opening'?

December 27, 2007, 18:03

Hi,

I am trying to simulate single phase (water) flow in a single cone cyclone. It has got one inlet and two outlets.

Should I specify one of these two outlets as 'opening'?

I felt to ask this question because the ANSYS CFX-Solver Modeling Guide (Release 11) Page 51 first paragraph says that "with more than two inflows or outflows, the other openings should be of the boundary type 'Opening'. This is because the flow at these other boundaries could in general be in or out, and the direction will be part of the solution."

Can some body help me to understand its meaning?

Many Thanks,

Regards, KM

January 1, 2008, 03:12

It would be problem specific depending on your physical conditions. Do you have a inflow in one of the two outlets?

January 2, 2008, 06:03

Both outlets you give as an Opening BC, That will gives you the better solution , than giving thg the one as opening.

December 27, 2007, 18:03	should one of the two outlets be 'opening'?	#1
KM Guest Posts: n/a	Hi, I am trying to simulate single phase (water) flow in a single cone cyclone. It has got one inlet and two outlets. Should I specify one of these two outlets as 'opening'? I felt to ask this question because the ANSYS CFX-Solver Modeling Guide (Release 11) Page 51 first paragraph says that "with more than two inflows or outflows, the other openings should be of the boundary type 'Opening'. This is because the flow at these other boundaries could in general be in or out, and the direction will be part of the solution." Can some body help me to understand its meaning? Many Thanks, Regards, KM

January 1, 2008, 03:12	Re: should one of the two outlets be 'opening'?	#2
Omer Guest Posts: n/a	It would be problem specific depending on your physical conditions. Do you have a inflow in one of the two outlets?

January 2, 2008, 06:03	Re: should one of the two outlets be 'opening'?	#3
Pratap Kumar DVS Guest Posts: n/a	Both outlets you give as an Opening BC, That will gives you the better solution , than giving thg the one as opening.

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