Flow over a cylinder
Flow over a cylinder
Aim:
To run the transient flow simulation over a cylinder using solidworks simulation.
objectives:
- To Calculate the baseline case Reynolds number.
- Then increase the Reynolds number by a factor of 20%, 40%, and 100% then run the transient flow simulation.
- To Create animations for pressure-velocity for all the three Reynolds number.
Procedure:
Geometry creation
- creating a circle of radius=0.02m.
- Extrude it for lenght=0.05m.
Settiing boundary conditions:
- Selcting external flow.
- Inlet velocity=10m/s and other input parameters are kept standard.
Meshing:
Creating pressure and velocity cut plots which will be helpful during animation.
Running and creating animation for each case.The Simulation end time for each case is calculated and set during simulation.
It is calculated using Time=Distance/Velocity
The distance was 0.36m and for each velocity we calculated time which is 0.03s for 12m/s and 0.0257s for 14m/s and 0.018 for 20m/s.
Code for calculation of Renolds numbers and respective velocities:
# Code to calculate velocity
# by Abhhishek Savakar
D=0.04
ro=1.204
dy=1.825e-5
v=10
# calculating renolds number
re=(ro*v*D)/dy
print('Renolds number Calculated for 10m/s velocity:',re)
print('Renolds number for factor 20%:',re*1.2)
print('Renolds number for factor 40%:',re*1.4)
print('Renolds number for factor 100%:',re*2)
Re_list=[re*1.2,re*1.4,re*2]
print(Re_list)
# calculating velocity for above renolds number
for i, Re in enumerate (Re_list,1):
v=(dy*Re)/(D*ro)
print(f'v{i}: {v}m/s')
Output:
Results:
At v=10m/s, pressure animation
At v=10m/s, velocity animation
At v=12m/s, pressure animation
At v=12m/s, velocity animation
At v=14m/s, pressure animation
At v=14m/s, velocity animation
At v=20m/s, pressure animation
At v=20m/s, velocity animation
Conclusion:
With the increase Renolds number, the inlet velocity increases. We obsevered that flow sepation after passing the cylinder also increases.