MODELLING AND SIMULATION OF FLOW THROUGH A FLOWBENCH
AIM: TO CREATE A MODEL AND RUN A FLOW SIMULATION OF FLOW THROUGH A FLOWBENCH USING SOLIDWORKS CFD.
OBJECTIVE:
- To create a 3D model a flow bench.
- To perform Flow simulation study.
- To obtain a plot for lift vs mass flow rate.
- To obtain a plot for velocity variation.
- To obtain a plot of flow trajectory.
- To perform grid dependency test.
- To run parametric sweep to show the effect of valve lift on mass flow rate.
- To compare the mass flow rate for following conditions-
|
Study number |
Valve lift |
|
1 |
1 mm |
|
2 |
2 mm |
|
3 |
3 mm |
|
4 |
4 mm |
|
5 |
5 mm |
OVERVIEW:
An air flow bench is a device used for testing the internal aerodynamic qualities of an engine component and is related to the more familiar wind tunnel.
It is used primarily for testing the intake and exhaust ports of cylinder heads of internal combustion engines. It is also used to test the flow capabilities of any component such as air filters, carburetors, manifolds or any other part that is required to flow gas. A flow bench is one of the primary tools of high-performance engine builders, and porting cylinder heads would be strictly hit or miss without it.
A flow bench consists of an air pump of some sort, a metering element, pressure and temperature measuring instruments such as manometers, and various controls. The test piece is attached in series with the pump and measuring element and air is pumped through the whole system. Therefore, all the air passing through the metering element also passes through the test piece. Because the volume flow rate through the metering element is known and the flow through the test piece is the same, it is also known. The mass flow rate can be calculated using the known pressure and temperature data to calculate air densities, and multiplying by the volume flow rate.
PROCEDURE:
Firstly, we will create a model of the flow bench
Now creating the lids
To start the flow simulation, we will provide some initial conditions like Unit System, Fluid type, Analysis type, Thermodynamic parameters etc.
Unit System
Fluid type
Analysis type
Now defining the boundary conditions for the study, as -
Total pressure
Static pressure
Global mesh setting
Setting up the Goals, as –
Mass flow rate
Flow trajectory
Creating Cut plane for Velocity
Then by clicking on the “run”
For various valve lift conditions, we will run the parametric study, as –
RESULTS:
1. Grid dependency test
We will evaluate the model at three grid sizes as ‘3’,’5’,’7’ for a particular valve lift of ‘1 mm’.
Study-1 (For grid size=3)
Velocity
Flow trajectory
Mass flow rate plot
Mass flow rate value
Study-2 (For grid size=5)
Velocity
Flow trajectory
Mass flow rate plot
Mass flow rate value
Study-3 (For grid size=7)
Velocity
Flow trajectory
Mass flow rate plot
Mass flow rate value
Conclusion -
So, by the above plots and studies it is clear that as the grid size is increased, the results are more refined. Mesh grid setting at ‘7’ is more accurate.
Now, we will proceed with grid size = 7.
2. Effect of Valve lift
Study-1 (1 mm valve lift)
Velocity
Flow trajectory
Study-2 (2 mm valve lift)
Velocity
Flow trajectory
Study-3 (3 mm valve lift)
Velocity
Flow trajectory
Study-4 (4 mm valve lift)
Velocity
Flow trajectory
Study-5 (5 mm valve lift)
Velocity
Flow trajectory
CONCLUSION:
We can conclude from the following plot that mass flow rate increases with a decreasing slope as the valve lift is increased.
Link for Plots, Results –
https://drive.google.com/file/d/1A5EDgOYPJhsVzri7cbIwosuH6M46xIA3/view?usp=sharing