Pipe flow simulation

Aim:

• Run a pipe flow simulation with an inlet Reynolds number of 100,1000 and 10,000.
• For each of these cases do the following

1. Place line probes at 95%, 90% and 85% of the pipe length.
2. Compare the normalized velocity profile at each of these locations
3. Normalize the velocity profile by the inlet velocity.

Theory:

Geometry:

• A CAD model of a hollow cylinder or pipe was made using SOLIDWORKS 2017, having the dimension as follows:

1. External diameter of pipe=0.05m
2. Internal diameter of pipe=0.048m
3. Length of pipe=1 m
4. Thickness of pipe=0.002m

Boundary condition:

• Inlet velocity = 0.00185 m/s when R=100

= 0.0185 m/s when R=1000

=0.185 m/s when R=10,000

• Static pressure = 101325 Pa

Temperature = 293.2 K

• Wall type: Real wall

Procedure:

• The model was created in SOLIDWORKS of the following dimensions mentioned in above.
• Then probes were created at the 95%, 90% and 85% of the length of the pipe.
• Now the wizard option was selected in the flow simulation feature of SOLIDWORKS and the necessary conditions were set up.
• First, lids were created at open ends. The lids help us to create the boundary condition.
• The necessary conditions were: Setting the flow simulation to internal, Taking the simulation fluid as water.
• As we have to perform a flow simulation so we need to consider a fluid Which will flow through this pipe.

Here we are considering water as our major flowing fluid. velocity is calculated as follows:

Fluid characteristics

• Fluid used: water
• Dynamic viscosity: 8.9×10^-4Pa.s
• Density of water: 1000 kg/m^3

Reynolds number equation:

where:

• Ris the Reynolds number, which is unitless
• ρis the fluid density in kilograms-per-cubic-meter (kg/m^3)
• vis the velocity in meters-per-second (m/s)
• Dis the diameter of the pipe in meters (m)
• μis the viscosity of the fluid in Pascal-seconds (Pa⋅s)

Velocity at different Reynolds numbers:

1. R=100 ; V=0.00185 m/s
2. R=1000 ; V=0.0185 m/s

• R=10,000 ; V=0.185 m/s
• After these calculations go to the insert boundary and create boundaries Like Inlet Velocity at Lid1, static Pressure at Lid2, Real wall across the length of the pipe.
• Make cut plots Across the Probes.
• when we finish doing the above steps. We will perform the Parametric Study.
• This parametric study Will give us very refined plots For Different Reynolds numbers at various design points.

Outputs:

• Re=100, v=0.00185m/s

Probe at 95%

Probe at 90%

Probe at 85%

• Re=1000, v=0.0185m/s

Probe at 95%

Probe at 90%

Probe at 85%

• Re=10000, v=0.185m/s

Probe at 95%

Probe at 90%

Probe at 85%

Variation of velocity at 95% of length for different reynolds number:

Design point 1-Re=100

Design point 2-Re=1000

Design point 3-Re=10000

Variation of velocity at 90% of length for different reynolds number:

Design point 1-Re=100

Design point 2-Re=1000

Design point 3-Re=10000

Variation of velocity at 85% of length for different reynolds number:

Design point 1-Re=100

Design point 2-Re=1000

Design point 3-Re=10000