Simulating an external flow Boundary Conditions

Project Support
1

Hi,

I am trying to simulate an aircraft flying at a certain altitude but not sure what type of boundary condition to choose for inlet.

Should i be using a velocity inlet Fixed Value or a Freestream when selecting the boundary condition. My aircraft would be stationary in the sky but the air will move at a speed of 236m/s.

The image below shows options for velocity type, i am not sure whether to use fixed value or freestream value, is there even a difference between them.

image
image2256×1504 473 KB

Kind regards,

Syed

2

Hi @syedalam786123 ,

I suggest you use ‘Fixed value’ for that inlet BC. However you will possibly fail with ‘Incompressible’ type of simulation, as your plane velocity is ~0.74 Mach. In that case ‘Compressible’ is appropriate and here you have the reference to similar project:

https://www.simscale.com/forum/t/compressible-aerodynamics-of-commercial-aircraft-simulation-project-by-ali-arafat/1142/2

Take care,

Retsam