Modelling and simulation of flow through a flowbench
Case setup:
1. Valve lift = 0.002 m
2. Boundary conditions:
Inlet pressure= Total pressure 101325 Pa
Outlet pressure= Static pressure 95000 Pa
3. Goals:
SG Mass Flow Rate1 for measuring the mass flow rate coming out of the outlet
A. Grid Dependence test:
Valve lift was kept constant for 3 runs while the cells in the X, Y and Z directions were changed. The results of the 3 runs are shown below in the form of velocity cut-plots.
|
Test No. |
Cells in X-axis | Cells in Y-axis | Cells in Z-axis |
| Mesh 1 | 12 | 14 | 8 |
| Mesh 2 | 24 | 28 | 16 |
| Mesh 3 | 36 | 42 | 24 |
Mesh 1:
Mesh 2:
Mesh 3:
From the above results, we can see that the Mesh 3 captures the flow accurately and more distinctively than the other two meshes.
So Mesh 3 is selected for the future parametric study.
Flow Trajectories:
Link to the video of the flow trajectory is: Animation
B. parametric Study for different valve lifts:
Keeping the mesh size of Mesh 3, New Parametric study is conducted for different valve lifts.
The valve lift is changed from 0.002m to 0.008m in 8 steps.
i. Valve Lift 0.002m:
ii. Valve lift 0.003m
iii. Valve lift 0.004m
iv. Valve lift 0.005m
v. Valve lift 0.006m
vi. Valve lift 0.007m
vii. Valve lift 0.008m
Results:
| Valve Lift (m) | Mass Flow rate (kg/s) |
| 0.002 | 0.017 |
| 0.003 | 0.0211 |
| 0.004 | 0.0245 |
| 0.005 | 0.0264 |
| 0.006 | 0.0288 |
| 0.007 | 0.0305 |
| 0.008 | 0.0319 |
The negative sign in the results shows that the mass is leaving the system.
Also, as the valve lift increases the velocity speed also increases in the port area.
Mass Flow rate plot vs valve Lift