OPEN CHANNEL ANALYSIS - Results Interpretation

[jorge.lopera]

Hi,

I have to calculate the time to drain a tank, I have found some formulas, but I wish to know If Simulation Multiphysics it has any way to interpretate the results, this is the workflow what I followed:

1. Import a CAD model  from SImulation MP, for example a cylinder with a little extrude to represent the outlet.

2. Define the mesh, for boundary layer.

3. Define the Top surface as a inlet/outlet, and the bottom surface too, this two surfaces must be for exclusion for boundary layer.

4. Define like 5 seconds (Pparameters) with different steps between each second.

5. Check that the gravity is working.

6. Then Run de analysis.

The question is, If I use the equation for fluid drain in a tank or recipent, that equation gives me an idea for the time that the fluid leaves the recipient. For example:

t=(A√(2h_1 ))/(〖A_o C〗_q √g)

But, when I define the Open Channel Model Parameters, define a time, like 10 seconds.,with several steps for each second.

For example, when I run, I have just see the results. That results appears like the flow it has continusly flow, not likes the aire displace the water. Y have just tried to read the User Guide (http://wikihelp.autodesk.com/Simulation_Mechanical/enu/2013/Help/0031-Autodesk31/0193-Analysis193/02...).

Then I need to estimate an approach about the time that I need to evacuate a fluid from a tank.

Please any help y I will aprecciate.

Regards,

[AstroJohnPE]

Hello Jorge,

This may be a silly question, but what is the analysis type set to? (It should be set to Open Channel.)

I think you only need to define an inlet/outlet surface on the outlet of your model. There is no water entering the top of the model, so that surface is not an inlet/outlet.

Also, you did not mention that you defined the initial volume (model either completely filled or partially filled), but I assume you did that.

[jorge.lopera]

Thanks john for the inlet/outlet advice.

At my model If I defined the model without Initial Volume, for example, All Fea part with volume filled, how I define the Initial Volume?


Do you where do I found samples about it?

Thanks

[jorge.lopera]

I attached the model that I want to calculate the time to drain....

Imagine all the solid filled with water....

[AstroJohnPE]

From looking at the "Getting Started > Help > Tutorials" command, I do not see any tutorials for the Open Channel Flow analysis type. Perhaps one of the other readers has created an open channel flow model example/tutorial and can share it.

For setting the initial fluid volume, my suggestion is to go to "Getting Started > Help > Online Wiki Help" and type "initial volume" in the search box. This will lad you to the page titled Initial Fluid Volume which describes the procedure.