I have a fan which draws air from sides and pushes out radially which boundary condition should i take?

i have a fan which draws air from sides and pushes out radially

which boundary condition

should i take?

Hey there, and thanks for using the forum!

This could be modeled in a few ways, depending in the level of detail you need to capture.

Some questions that might help here:

  1. Do you need to take into account the fan blades geometry?
  2. How is the fan located with respect to the overall flow region?
  3. Is this a ducted fan/flow is channeled through ducts?

Some options would be:

  1. Simple Inlet/Outlet BCs to model fan-produced flow.
  2. Use a momentum source.
  3. Include the fan geometry with MRF rotating zone.
  4. Include the fan geometry with AMI rotating zone.

Please refer to our documentation for details on this procedures, we have a really nice search tool.

simple bro.

fan outward flow is in z direction.

please look at my project and suggest me the boundary conditions to take.

Where would the fan be? Please use an image for clarity.

on the top of the fins…flow direction will be outwards the fins and i’d like know whether i’ve to put natural convection and velocity outlet(flow rate) or velocity inlet from four sides and pressure outlet from top side.

For this you can use a velocity outlet, with flow rate to match the fan output.

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Check this article:

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By the way, your flow region walls are too close to the parts, creating small gaps that mess up with meshing ans simulation. Please improve this by increasing the size of the enclosure, or making it fit exactly.

where can i get a Heat transfer coefficient value after processing ?

i saw a graph named ‘h j/kg’ but that isnt a heat transfer coefficient .