CFD Online Discussion Forums - Time-averaged velocity plot for a transient simulation

Quote:

Originally Posted by mali28 (Post 337968)

Hi,

I want to plot a time-averaged cross-sectional velocity profile plot.

I can plot the velocity profile for a specific time, but how do can I plot time-averaged velocity profile for a specific range of time interval.

Can any one help me?

Thank you.

Hello Mali28.

I've been working on the same problem for the past couple days. Here's what I have so far.

I am using ANSYS FLUENT 19.2. I am doing a 2D transient simulation of two mixing flows: gas and water. Water boundary conditions are steady, gas boundary conditions (pressure and velocity) are transient.
First of all, it turns out that FLUENT does not do 2D simulations exactly. I.e. when I did meshing and solved the problem, I saw that FLUENT automatically converted my 2D schematic to a 3D one with a width equal to a mesh cell width. That's what helped me to do area averaging.
Overall:

1) I opened workbench.
2) I did geometry --> then I did mesh --> then I did setup --> then I did solution
3) Then I exited solution and returned back to the workbench
4) Then I opened results

5) In results: Location --> Plane
6) It will offer you several options to create a plane
7) There will be an option to define a plane perpendicular to z axis and parallel to xy plane (it is for my case - you can choose other options), also it will allowg you to define the sizes of your plane

8) I did 2D. Therefore, the length of my plane was equal to the width of my geometrical 2D form - it is easy to guess
9) But what about the width of my plane? The width is equal to the mesh cell size which I specified in the setup for my solution
10) That's how I created a cross sectional plane in which I wanted to find cross sectional averaged pressure
11) Go to "function calculator". It's icon looks like an "f" in front of a calculator. It's at the end of the same row in which "locations" are placed.
12) There, under the section "Function Calculator" you will see different options: "Function", "Location", "Case" and so on. You need "Function".
13) In "Function" choose "areaAve".
14) Then hit "calculate"
15) You will see your area averaged pressure (In my case I needed pressure - you can do whatever you want).

So, the overall idea is very simple and simultaneously hard to guess. Whenever you need to do area averaging AFTER your calculations have been done, first create a plane in which you will be doing your averaging, second, use "Function Calculator".