calculating mass flow rate through interior holes

tricha122 · March 20, 2018, 13:18

Hi, I have many holes that have an incompressible fluid flowing through them. I'd like to be able to create a plane by specifying a centroid and normal, and a size to that plane (either rectangular or circular) and calculate the averaged mass flow traversing that plane. (this would be repeated for all interior holes)

Is this possible in CFX?

Any help would be greatly appreciated!

ghorrocks · March 20, 2018, 17:31

You can define limits to planes in CFX. It is a bit weird so alternatives include drawing the entire plane, then using contours of x and y or radius to define the shape and generating a user surface on the contour line. This is more complex but you get better control over what you are doing.

Gert-Jan · March 21, 2018, 03:49

Hi Taylor,

You mention CFX. But do you mean you want to monitor the flow through the holes during your run? Or after wards in the postprocessing?

You can do the first by creating internal surfaces in each hole, mesh them and then in CFX-Pre define interfaces there. This allows you to monitor the flow through each hole.

The latter case, in CFD-Post, is very simple. I do it on a daily basis.
You can create a plane based on a point an a normal.
Then you can limit the size of that plane given a rectangular or circular shape, so that it covers only the hole of interest.
Then if you calculate the mass flow through that plane, it limits itself to the shape you provided. Or, as an example, you can calculate the mass flow average Temperature.

March 20, 2018, 13:18	calculating mass flow rate through interior holes	#1
tricha122 Member Tyler Richardson Join Date: Jun 2017 Posts: 30 Rep Power: 9	Hi, I have many holes that have an incompressible fluid flowing through them. I'd like to be able to create a plane by specifying a centroid and normal, and a size to that plane (either rectangular or circular) and calculate the averaged mass flow traversing that plane. (this would be repeated for all interior holes) Is this possible in CFX? Any help would be greatly appreciated!

March 20, 2018, 17:31		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	You can define limits to planes in CFX. It is a bit weird so alternatives include drawing the entire plane, then using contours of x and y or radius to define the shape and generating a user surface on the contour line. This is more complex but you get better control over what you are doing. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

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March 21, 2018, 03:49		#3
Gert-Jan Senior Member Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,928 Rep Power: 28	Hi Taylor, You mention CFX. But do you mean you want to monitor the flow through the holes during your run? Or after wards in the postprocessing? You can do the first by creating internal surfaces in each hole, mesh them and then in CFX-Pre define interfaces there. This allows you to monitor the flow through each hole. The latter case, in CFD-Post, is very simple. I do it on a daily basis. You can create a plane based on a point an a normal. Then you can limit the size of that plane given a rectangular or circular shape, so that it covers only the hole of interest. Then if you calculate the mass flow through that plane, it limits itself to the shape you provided. Or, as an example, you can calculate the mass flow average Temperature.