Channel flow simulation using CONVERGE CFD
Objective:
To simulate the flow of fluid in a channel using CONVERGE for 3 different base mesh sizes are,
- dx = 2e-4m, dy = 2e-4m, dz = 2e-4m
- dx = 1.5e-4m, dy = 1.5e-4m, dz = 1.5e-4m
- dx = 1.0e-4m, dy = 1.0e-4m, dz = 1.0e-4m
Contents to be shown in the report:
1. Velocity and pressure contours for all the 3 base mesh sizes.
2. Showing the mesh (i.e surface with edges) for the 3 base mesh sizes.
3. Plotting of velocity, pressure, mass flow rate and total cell count for all 3 base mesh sizes.
Geometry:
The geometry is created using the create geometry option. the dimensions are as follows:
x = 0.1 m
y = 0.01 m
z= 0.01 m
The normal direction set correctly for the flowing working fluid correctly in the channel
The boundary conditions:
The Inlet Pressure = 100001 Pa
The Outlet Pressure = 100000 Pa
The Top and Bottom surface are given as wall with a no-slip boundary condition.
The working fluid is chosen as AIR
The species composition
O2 = 0.23
N2 = 0.77
Considering 3 different base mesh sizes are,
case-1:
dx = 2e-4m, dy = 2e-4m, dz = 2e-4m
case-2:
dx = 1.5e-4m, dy = 1.5e-4m, dz = 1.5e-4m
case-3:
dx = 1.0e-4m, dy = 1.0e-4m, dz = 1.0e-4m
For all three grid size the simulation has run for 50000 cycles to attain the convergence
case-1:
dx = 2e-4m, dy = 2e-4m, dz = 2e-4m
Base Grid:
The baseline grid mesh for case-1 is showed in the figure below.
Velocity contours:
The Velocity contours for case-1 is showed in the figure below.
Velocity Plot Using Paraview:
The line over plot is used to see the behavior of velocity in the channel in the x-direction.
pressure contours:
The Pressure contours for case-1 is showed in the figure below.
Velocity Plot:
Line module in Converge has been used to see the velocity and from the below plot we clearly concluded that the flow is converged.
Static Pressure plot:
Line module in Converge has been used to see the Static-pressure and from the below plot we clearly concluded that the flow is converged.
Mass flow rate plot:
Line module in Converge has been used to see the Mass flow rate and from the below plot we clearly concluded that the flow is converged.
Total cell count plot:
The total cell count was nearly 25000 for the base grid size 0.0002 and by adding the rank(0,1,2,3) we are getting a cell count of 25000 total cells
Animation for case-1:
The animation of the flow through the channel can be seen in the link below. The initial oscillation nature dies down and when the simulation reaches the steady-state.
https://youtu.be/CsQJ-I8PaYI
case-2:
dx = 1.5e-4m, dy = 1.5e-4m, dz = 1.5e-4m
Base Grid:
The baseline grid mesh for case-2 is shown in the figure below
Velocity contours:
The Velocity contours for the case-2 is showed in the figure below.
Velocity Plot Using Paraview:
The line over plot is used to see the behavior of velocity in the channel in the x-direction.
pressure contours:
The Pressure contours for the case-2 is showed in the figure below.
Velocity Plot:
Line module in Converge has been used to see the velocity and from the below plot we clearly concluded that the flow is converged.
Static Pressure plot:
Line module in Converge has been used to see the Static-pressure and from the below plot we clearly concluded that the flow is converged.
Mass flow rate plot :
Line module in Converge has been used to see the Mass flow rate and from the below plot we clearly concluded that the flow is converged.
Total cell count plot:
The total cell count was nearly 48000 for the base grid size 0.00015 and by adding the rank(0,1,2,3) we are getting a cell count of 48000 total cells. When compared to case-1 there is an increase in the cell count.
Animation for case-2:
The animation of the flow through the channel can be seen in the link below. The initial oscillation nature dies down and when the simulation reaches the steady-state.
https://youtu.be/JQ9NOFpPt6E
case-3:
dx = 1.0e-4m, dy = 1.0e-4m, dz = 1.0e-4m
Base Grid:
The baseline grid mesh for case-3 is shown in the figure below
Velocity contours:
The Velocity contours for case-3 is showed in the figure below
Velocity Plot Using Paraview:
The line over plot is used to see the behavior of velocity in the channel in the x-direction.
Pressure contours:
The Pressure contours for the case-3 is showed in the figure below.
Velocity Plot:
Line module in Converge has been used to see the velocity and from the below plot we clearly concluded that the flow is converged.
Static Pressure plot:
Line module in Converge has been used to see the Static-pressure and from the below plot we clearly concluded that the flow is converged.
Mass flow rate plot :
Line module in Converge has been used to see the Mass flow rate and from the below plot we clearly concluded that the flow is converged.
Total cell count plot:
The total cell count was nearly 100000 for the base grid size 0.0001 and by adding the rank(0,1,2,3) we are getting a cell count of 100000 total cells. When compared to case-2 there is an increase in the cell count.
Animation for case-3:
The animation of the flow through the channel can be seen in the link below. The initial oscillation nature dies down and when the simulation reaches the steady-state.
https://youtu.be/BI-VdeEsKug
CONCLUSION :
- As the base grid size is decreased, it can be seen that the total cell count is increased.
- From the above velocity contours, the parabolic nature of flow can be seen The contours get smoother as the mesh is finer.
- The images of the mass flow rates have shown that mass is conserved.