Home / Examples / Simple Fluid Analysis [Pascal] / Example 1: Air Flow in Cylinder
Steady-state analysis is performed for the the air flowing through a cylinder.
The air flow is assumed to be laminar, non-viscous and incompressible.
The distribution of the flow velocities is solved.
Unless specified in the list below, the default conditions will be applied.
Results will vary depending on Femtet version and the PC environment.
Item |
Settings |
Analysis Space |
3D |
Model Unit |
mm |
Item |
Settings |
Solver |
Simple Fluid Analysis [Pascal] |
Analysis Type |
Steady-state Analysis |
Options |
N/A |
The fluid (Air) in the cylinder is created as a solid body and defined as "Fluid" in the material property.
The body obstructing the flow is a solid body and defined as "Solid" in the material property.
Body Number/Type |
Body Attribute Name |
Material Name |
0/Solid |
Air |
000_Air(*) |
1/Solid |
Solid |
Solid |
* Available from the material DB
Air is set as below.
Material Property Name |
Tab |
Settings |
Air |
Solid/Fluid |
State: Fluid |
The flow velocity is given at the inlet and the velocity potential is given at the outlet.
The velocity potential is set to 0 [m^2/s], resulting in the output opening.
The details are explained at [Fluid] tab of the boundary condition.
Boundary Condition Name/Topology |
Tab |
Boundary Condition Type |
Settings |
in/Face |
Fluid |
Flow Velocity |
1 [m/s] |
out/Face |
Fluid |
Velocity Potential |
0 [m^2/s] |
The distribution of the flow velocities is shown below.
The flow velocity is higher in the obstructed area, about twice as large as in the non-obstructed area.