Open channel flow


Hi, I’m a newbie to CFD. I’ve imported a model of a culvert, which is basically an open channel with water flowing into two pipes. I can’t figure out how to define the boundary condition on top of the channel so i get open channel results.

The pipes can flow part full at low flow rates. How do I set the outlet BC? I’m using flow rate at present.


@steve22 - thanks for your question and welcome to SimScale!

I’m adding your project link to this thread:


For the outlet conditions, I’d recommend using a zero pressure outlet:

Also had a look at your Topo entity sets and your missing some wall faces (I assume they are quite small). I think there should be 27.

I’m running the simulation now and will get back to you with the results as soon as they are ready



You’ll find my simulation runs here - I also ran some multiphase simulations to model low flows: