Flow rate

Sly787 · December 8, 2010, 11:35

Hi, I have to find how a flow rate changes in time.
I model my nozzle driven by pressure BC and I must insert a 2D plane, and the nozzle end, to control flow rate across this. I have to find a time-behavior of flow rate.
How can I do in Flow-3D?

MuxaB · January 17, 2011, 02:45

Quote:

Originally Posted by Sly787

Hi, I have to find how a flow rate changes in time.
I model my nozzle driven by pressure BC and I must insert a 2D plane, and the nozzle end, to control flow rate across this. I have to find a time-behavior of flow rate.
How can I do in Flow-3D?

Use a flux surface, which is a flat baffle with IBAF(1)=1. It will compute and output the total flow rate through it.

aginor · January 17, 2011, 20:49

i also have a similar problem. i can view the results from this baffle. where are they?

aginor · January 17, 2011, 20:59

this is my baffle. the result is always a zero. but i have flow throw this baffle.
nbafs=1, ifbaf(1)=1, bxl(1)=0., bxh(1)=0.5,
byl(1)=0., byh(1)=1., bzl(1)=0., bzh(1)=0.2, FPTITL(1) ='sxara',

JBurnham · January 18, 2011, 12:19

I think you have the baffle defined incorrectly. You've 'limited' min and max x's, y's, and z's, which would create a 3-D cube, but this is not how FLOW-3D interprets a baffle. You can keep two sets of the 'limiters' (byl, byh & bzl, bzh for example), remove the x-limiters, and specify one plane 'definition' in x in which the baffle appears (and is limited): bx = 0.25, for example. As you have it defined currently, FLOW-3D is probably just ignoring it during preprocessing. Check your preprocessor messages and errors.

MuxaB · January 19, 2011, 01:35

Quote:

Originally Posted by aginor

i also have a similar problem. i can view the results from this baffle. where are they?

Once you open the flsgrf file, the results from a flux surface baffle will be in Probe > General history data catalog, along with all other mesh-independent quantities such as fluid volume and kinetic energy, as a function of time.

December 8, 2010, 11:35	Flow rate	#1
Sly787 New Member Join Date: Nov 2010 Posts: 5 Rep Power: 16	Hi, I have to find how a flow rate changes in time. I model my nozzle driven by pressure BC and I must insert a 2D plane, and the nozzle end, to control flow rate across this. I have to find a time-behavior of flow rate. How can I do in Flow-3D?

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January 17, 2011, 20:49		#3
aginor New Member Nikolaidis Giorgos Join Date: Jan 2011 Posts: 4 Rep Power: 15	i also have a similar problem. i can view the results from this baffle. where are they?

January 17, 2011, 20:59		#4
aginor New Member Nikolaidis Giorgos Join Date: Jan 2011 Posts: 4 Rep Power: 15	this is my baffle. the result is always a zero. but i have flow throw this baffle. nbafs=1, ifbaf(1)=1, bxl(1)=0., bxh(1)=0.5, byl(1)=0., byh(1)=1., bzl(1)=0., bzh(1)=0.2, FPTITL(1) ='sxara',

January 18, 2011, 12:19		#5
JBurnham Senior Member Jeff Burnham Join Date: Apr 2010 Posts: 204 Rep Power: 17	I think you have the baffle defined incorrectly. You've 'limited' min and max x's, y's, and z's, which would create a 3-D cube, but this is not how FLOW-3D interprets a baffle. You can keep two sets of the 'limiters' (byl, byh & bzl, bzh for example), remove the x-limiters, and specify one plane 'definition' in x in which the baffle appears (and is limited): bx = 0.25, for example. As you have it defined currently, FLOW-3D is probably just ignoring it during preprocessing. Check your preprocessor messages and errors.