Modelling and simulation of flow through a flowbench

Aim : To create project of 3D model of flow bench and run flow analysis. And obtain a plot of lift vs mass flow rate.

Introduction :

Grid dependence test is also called as mesh dependence test in which the model is subjected to successive smaller cell sizes for calculations, that is the model is divided into smaller number of parts called elements and calculations are made. As the element size decreases the error towards the results reduces. Now for the above 3D model we run the simulation with three refining values.

Procedure :

• 3D model :

First create a cylinder and valve with the given dimensions.

External diameter of cylinder : 0.10m.

External diameter of inlet port : 0.025m.

Shell : 0.0015m.

• Boundary condition

create a new flow simulation project and Insert Boundary Condition as intel as total pressure and outlet as static pressure and insert surface goals as mass flow rate.

Intel Total Pressure : 172369 Pa at temperature 293.2 K.

Outlet Static Pressure : 101325 Pa at temperature 293.2 K.

• Perform GRID DEPENDENCY TEST

Now for the above 3D model we run the simulation with three refining values.

Valve lift is taken as 5mm.

Level of refining of cells is 2

Level of refining of cells is 3

Level of refining of cells is 4

From result we can say that the results greatly depend on the level of refining the fluid cells.

4. ) EFFECT OF VALVE LIFT ON THE MASS FLOW RATE

now parametric sweep to show the effect of valve lift on mass flow rate is run and the cut plots of the velocity variations are shown in the figures below.Valve lift on mass flow rate with different rang 0.001m to 0.008m, and cut plots of velocity

Valve lift of 1mm

Valve lift of 2mm

Valve lift of 3mm

Valve lift of 4mm

Valve lift of 5mm

Valve lift of 6mm

Valve lift of 7mm

	Design Point 1	Design Point 2	Design Point 3	Design Point 4	Design Point 5	Design Point 6	Design Point 7
D9@[email protected] [m]	0.001	0.002166667	0.003333333	0.0045	0.005666667	0.006833333	0.008
SG Mass Flow Rate 1 [kg/s]	-0.030370162	-0.061620785	-0.082185198	-0.099925955	-0.110723063	-0.117655247	-0.121920084

The above table shows the valve lift, mass flow rate

• The parametric study is conducted at three design points 1, 2, 3, 4, 5, 6, 7 and 8 which is the valve lift 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm and 8mm respectively .
• The grid dependency test is made for the same refining value of 4.
• Graphs for pressure drop, mass flow rate and total pressure at outlet with respect to the design points are made as follows.

5. ) Flow Trajectories

Velocity

pressure :

6. ) Surface goals of mass flow rate.

Conclusion:

Valve lifts gets increase’s, The value of Velocity and pressure are also increases and mass flow rate also get increased, when grid level gets increased we get more accuracy.