SimScale CAE Forum

Modeling a canister filter

Great program. I see many uses and like the functionality.
I am new to CFD and am trying model a canister filter that has a 4 inch port to 200 mH2O vacuum and a 2.5 inch port to atmosphere. It models well with just the two ports. When I add a dip tube 8 inches into the many canister body I can not get it to show the flow coming down the tube. The tube is added to force the intake flow to the bottom of the chamber.
I believe I am not setting up the solid model properly.
Any help would be appreciated.

Hi there, could you add an image to show how the fluid is expected to flow inside the model?

Best regards,

Actually I got it to work well. But now I need to make changes as I have to add a diverter and a baffle. I struggle with how to build the model so that it simulated properly. Maybe I have missed it but a tutorial on model building would be greatly helpful to demonstrate the concepts.
On You Tube show ho someone models a heat exchanger. That has tubes within tubes, Multiple inputs and outputs, etc.
I really like your program so if we get this model finished and working we will be other than a free subscriber.
Thank you for your quick response.

For our simple model here is the air flow.

Eventually we would like to model the filter with a baffle an diverter. On thei next picture you can \see the diverter at the box of the dip tube and the horizontal baffle.

I hope this helps

I sent the request diagrams, do you have any further comments.


Having a look at the diagrams, the last simulation run shows the exact behavior that you described:

The issue with some of the other simulations that you ran is that you were also selecting the side face of the dip tube as an inlet. This was causing a weird flow pattern:

Now, the velocities look extremely high here. Is it a 200 mH2O vacuum, or a 200 mmH2O vacuum?


1 Like

Thanks! I figured out the correct faces and the velocities are very high. I have the incorrect vacuum level and will fix that.
But my real need is to understand how to construct the model using solidworks. My first attempt was to use a model constructed using the rotated Boss command to produce the canister. But when looking at the mesh it was placed inside the two sides of the canister wall.
Next I just tried a solid canister and that worked but I can not add artifacts in the canister.
One of the online tutorials show the modeling of a intake of a gas turbine generator with turning veins. How do you model the turning veins? As solids or hollow objects?
While I see huge application for Simscale, building a model seems to me the most difficult part and the one with the most questions. It seems a turtorial would help. Your tutorials seem to spend most of the time telling the audience why they should use simulation rather than instructing us beginners how to get started.
Thanks for the help, while frustrated I do appreciate it!


The logic with geometries is pretty simple: for CFD, we are interested in obtaining the results in the fluid domain, so the base CAD model for a CFD simulation should contain the flow region, and not the solid walls.

If you have the solid walls of the model instead of the fluid domain, then you will mesh the walls instead of the flow domain. On a side note, it’s possible to create the fluid domain in SimScale with flow volume extraction operations.

On your question about turbine generators - I guess you are referring to rotating zones? If so, I’d recommend that you have a look at this documentation page with 2 examples of the CAD preparation, including the preparation of the geometry for the pump tutorial.

In short, you will need to use the flow region (i.e. you will subtract the blades/solid parts from the flow region), and add one separate volume for the rotating zone. The rotating zone volume is 100% solid and fully interferes with the flow region. The examples in the doc that I linked should give you more insights.


Thank you that helps.

1 Like

Do anyone of you any idea about the best canoster filters for 55 gallon tanks?

Here I have a list containing various ideas about canister filter for 55 gallon tanks. But I’m not sure which one is best, if possible then please help me out.