Air circulation in room, mass flow problem!!

sorkhani · June 16, 2020, 02:55

Hi guys,
My case is a room with inlet face and same face in another wall as outlet.
B.C in inlet is mass flow inlet
B.C in outlet is pressure outlet(0 pa)
After fluent solution converge, balance of mass in inlet and outlet is good.
Problem:
Why Velocity Magnitude is different for inlet and outlet boundries!!!!!?
Area is equal , density is constant.

FMDenaro · June 16, 2020, 03:25

Quote:

Originally Posted by sorkhani

Hi guys,
My case is a room with inlet face and same face in another wall as outlet.
B.C in inlet is mass flow inlet
B.C in outlet is pressure outlet(0 pa)
After fluent solution converge, balance of mass in inlet and outlet is good.
Problem:
Why Velocity Magnitude is different for inlet and outlet boundries!!!!!?
Area is equal , density is constant.

Could you superimpose the inlet and outlet velocity profiles on a single plot? I want to check the area of the curves.

sorkhani · June 23, 2020, 02:00

http://s12.picofile.com/file/8400849...623_102542.jpg
This is superimpose of velocity magnitude at diameter line of inlet and outlet (my case is 3D)

FMDenaro · June 23, 2020, 03:20

If the flow rate is the same in inlet and outlet that does not imply you must have the same velocity profiles.
However the outlet profile seems quite strange.

sorkhani · June 27, 2020, 05:23

this is my problem !!!
every convergence parameter is good, but the velocity is so wrong!!
when the outlet around area mesh is Hex, outlet velocity is equal to inlet vel.

June 16, 2020, 02:55	Air circulation in room, mass flow problem!!	#1
sorkhani New Member ali Join Date: Jul 2009 Posts: 12 Rep Power: 16	Hi guys, My case is a room with inlet face and same face in another wall as outlet. B.C in inlet is mass flow inlet B.C in outlet is pressure outlet(0 pa) After fluent solution converge, balance of mass in inlet and outlet is good. Problem: Why Velocity Magnitude is different for inlet and outlet boundries!!!!!? Area is equal , density is constant.

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June 23, 2020, 02:00		#3
sorkhani New Member ali Join Date: Jul 2009 Posts: 12 Rep Power: 16	http://s12.picofile.com/file/8400849...623_102542.jpg This is superimpose of velocity magnitude at diameter line of inlet and outlet (my case is 3D)

June 23, 2020, 03:20		#4
FMDenaro Senior Member Filippo Maria Denaro Join Date: Jul 2010 Posts: 6,768 Rep Power: 71	If the flow rate is the same in inlet and outlet that does not imply you must have the same velocity profiles. However the outlet profile seems quite strange.

June 27, 2020, 05:23		#5
sorkhani New Member ali Join Date: Jul 2009 Posts: 12 Rep Power: 16	this is my problem !!! every convergence parameter is good, but the velocity is so wrong!! when the outlet around area mesh is Hex, outlet velocity is equal to inlet vel.