Discussion Forum

Hi

when you select a physics, by default all domains are included in the main node (but you can remove some from this main physics node), and a few mandatory sub nodes are added with the domains of the main physics included, but greyed, as they have to be there as minimum to define a coherent set of equations. Mostly the last mandatory is the Initial condition node.

Now you can define new subnode and include any domain, up to the full set of the principal physics node in these, some of these sub-nodes will override the previous ones (you must read a node and it's sub nodes as a top-down sequence, so the order of the subnodes are important. You might even add so many new submodes that some of the initially mandatary sub nodes are full "over-ridden or superseeded" by the following ones.

I believe, from your question, that you have not yet full understood this logic of sub nodes and the and the difference of contributive (that adds something to a similar existing BC) and exclusive (something that replaces fully a previous sub-node) Boundary Condition (=BC

I hope I'm clear enough

node for the main physics
--sub-bnode (=contributive or exclusive BC)
----sub-sub-node
etc

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Good luck
Ivar

Thank you for your reply.

Mostly do not mind but there are instances when it bothers functioning model.

Good-bye.

Hi

it should not bother any model, you should always have the possibility to change, if not TO ADD a new node with complementary info. But each physics will have a minimum of node greyed to be consistent. But it could be that the user overwrites some or even ALL the mandatory nodes.

In other words, if you cannot diasable an item you need to redefine it which will superseed the element

--
Good luck
Ivar

Hello.

I would like to ask you a favor.
Try to do rotary model of AC / DC but it still does not work.
The library model is created geometry, and I do not know how some parts (identify a pair of stator) are doing.
I tried to create your own geometry.
Stationary to do everything.
But the rotor is not rotating.
I tried for more options (coil, permanent magnets ...).
I would like the model sent to the forum, but when I click attach fille nothing is performed.
And so I want to ask if you would not send me
Your email and I would send you my model.

Thank you very much for your help.

Goodbye.

Hi

probably your model is too big, in v4 you need to "Edit - Clear solution" and "Edit - Clear mesh" and "File - Reset model" then save into a new file and try to attach that one

rotary machines are complex to set up so you need some time and training to get there, try repeating the Library models for the 2D generator, once you can do it by yourself, try the 3D ...
Do not forget to read carefully the PDF doc as there are many things one can get wrong the first times

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Good luck
Ivar

Hello.

I tried physic
Rotating Machinery, Laminar Flow.
When I use the dimensions in mm all work well ..
But when Using the same geometry but 10 times biger (cm) writes me that error

Failed to find Consistent initial values​​.
Last time step is not Converged.

What should I do?
Is this physicist for larger sizes?

Thank you very much for your reply.

Hi

scaling the geoemtry is not always enough, you might need to scale some BC loads, values, and certainly check your mesh as its scale is dependeing on the physics of the flow and not on the size of the geometry. Not everything scale linearly with a side length ;)

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Good luck
Ivar

Hello.

It's not just geometry.
I also tried to change the conversion and the value is still there but I have the same mistake.

Thank you.

Hello.

I downloaded from this forum rot_1.mph file.
I have followed him, only slightly changed with the geometry.
Rot_1.mph works and the rotor spins.
In my case, the rotor standing.
Several times I looked both sets but I did not find cause.
You could look at these files and advise me why?

Thank you.

BTW

I can attach file.
Can anybody help me.
If I click to Atach file nothing happend.

Hi

probably the file is too big, try to Edit - Clear all solutions, - Clear all mesh, + File Reset history, and save as with a new name, then upload it, we will have to rerun the model thats the cost, but uploads are limited in size, not sure how big though

--
Good luck
Ivar