Setting a Velocity profile for a circular boundary
 

Dear all,

Could you recommend the best way to assign a velocity profile to a circular surface? I´m making a wind flow study on a circular domain, but I don´t know how to introduce the velocity boundary condition. How can I just assign a velocity magnitude and direction for this case when the velocity signal must change whit the angle?

Thanks in advance!

What is the geometry of the domain and what velocity profile would you like to implement? You can either specify a velocity boundary condition in the normal direction of each cell face or specify the velocity in each direction (x, y, z).

A cylinder delimits a portion of a hilly terrain where the wind blows with a heading of 120 degrees west of north. The velocity value could be positive or negative if the vector is entering or leaving the domain, respectively.

Thanks 'e'!

Break the vector up into components (x and y; as well as z in 3-D). For example, your 120 degrees west of north unit vector would be:



Under Define > Boundary Conditions... select the velocity inlet condition and use "Components" for the "Velocity Specification Method". Enter the unit vector (above) multiplied by your wind speed.

Thanks again 'e',