Modelling and simulation of flow through a flowbench

Aim: - Create a 3D model of a flow bench and run flow analysis then do the

• Grid dependence test
  • For three grids run your simulation at a particular valve lift .
• Effect of valve lift on mass flow rate
  • Once you have decided the best grid, run a parametric sweep to show the effect of valve lift on mass flow rate

Flow bench

• An 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.

• Model in solidworks

Flow simulation

• Select the internal flow with working fluid as air with default conditions
• Add boundary conditions
  • Inlet : - Total pressure = 506625Pa
  • Oulet : - Static pressure = 101325Pa
• Select global mesh size and add local mesh to the surface of valve
• Add global goal and surface goal of mass flow rate and cut plots of pressure and velocity

Grid dependence test

Open the valve by 4mm and run the new parametric study with input variable as automatic mesh size of 3 , 4 and 5 hence create 3 design study

Results

• Mass flow rate
  • negative sign indicates the exit of mass from the systum

• Velocity contours
  
  • Automatic mesh size 3
• • Automatic mesh size 4
• • Automatic mesh size 5

• Pressure contour
  • Automatic mesh size 3
• • Automatic mesh size 4
• • Automatic mesh size 5

• By increase the automatic mesh size number fine and small mesh is genrated which made the result more accurate but required more time to solve because the number of cell to calculate increase .
• We can see that by increasing the mesh size number velocity contour changes , mass flow rate exit the systum decrease and the pressure contour is changed by little factor So for next parametric study we will chose the automatic mesh size 4 because it will give results with medium accuracy in medium time

Effect of valve lift on mass flow rate

1mm Valve lift

Pressure contour Velocity countour

2 mm valve lift

Pressure countour Velocity countour

3 mm valve lift

Pressure countour Velocity countour

4 mm valve lift

Pressure countour Velocity countour

5 mm valve lift

Pressure countour Velocity countour

6 mm valve lift

Pressure countour Velocity countour

7 mm valve lift

Pressure countour Velocity countour

8 mm valve lift

Pressure countour Velocity countour

Valve lfit vs mass flow rate

GG Mass flow rate is the gobal mass flow rate that is different between the entry mass flow rate and the exit mass flow rate (mass flow rate entry - mass flow rate exit)

• From the velocity countour we can say that when we increase the valve lift the velocity is increased so for high velocity high valve lfit is required
• From the pressure countour we can say that when we increase the valve lift the pressure drop increased but it will also increase the cost
• As we increase the valve lift the mass flow rate is increased at both entry and exit of the flow bench but for higher valves of valve lift both will become constant