## Simulation Mechanical and Multiphysics

- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic to the Top
- Bookmark
- Subscribe
- Printer Friendly Page

# OPEN CHANNEL ANALYSIS - Results Interpretation

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Email to a Friend
- Report Inappropriate Content

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

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,

Nexsys de Colombia

# Re: OPEN CHANNEL ANALYSIS - Results Interpretation

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Email to a Friend
- Report Inappropriate Content

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.

Mechanical Engineer

Pittsburgh, PA

16.9 years experience with Simulation Mechanical

# Re: OPEN CHANNEL ANALYSIS - Results Interpretation

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Email to a Friend
- Report Inappropriate Content

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

Nexsys de Colombia

# Re: OPEN CHANNEL ANALYSIS - Results Interpretation

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Email to a Friend
- Report Inappropriate Content

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

Imagine all the solid filled with water....

Nexsys de Colombia

# Re: OPEN CHANNEL ANALYSIS - Results Interpretation

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Email to a Friend
- Report Inappropriate Content

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.

Mechanical Engineer

Pittsburgh, PA

16.9 years experience with Simulation Mechanical