Hi,

Does anybody can explain to me what is the difference between outlet vent and outflow?

thanks

AJG

Outflow is a very limited BC. It assumes fully developed flow, can't be used with Pressure Inlets, or compressible flow. It is useful in pipeflows for example, when you don't know the conditions of the flow, but you're BC is far enough downstream where the fully developed assumption holds true.

The outlet vent is like a pressure outlet (so it's a pretty versatile BC) combined with a loss coefficient. Here, you define what the pressure is "outside" of your vent, and the loss coefficient (which is a function of velocity) through the vent, and the backflow conditions. An example would be on an electronics box (like a computer). A fan would pull cool air into the box, and it would exit through a vent. The vent is going to induce some losses on the system (if you invent a vent that doesn't, then patent it and we'll split the profits...) and this BC is used to account for that.

Hope this helps, and good luck, Jason

Thanks man! really helpful your answer. AJG

[amey169]

Its been a long time for this thread, but hope someone replies to my query.

The loss coefficient which we provide for pressure drop through the vent, which pressure drop does it accounts for - the static pressure or total pressure?