Flow Simulation in SolidWorks

INTRODUCTION:

The Reynolds number (Re) is an important dimensionless quantity in fluid mechanics used to help predict flow patterns in different fluid flow situations. At low Reynolds numbers, flows tend to be dominated by laminar (sheet-like) flow, while at high Reynolds numbers turbulence results from differences in the fluid's speed and direction, which may sometimes intersect or even move counter to the overall direction of the flow.

The Reynolds number is defined as

where:

• ρ is the density of the fluid (SI units: kg/m³)
• u is the velocity of the fluid with respect to the object (m/s)
• L is a characteristic linear dimension (m)
• μ is the dynamic viscosity of the fluids (Pa·s or N·s/m² or kg/m·s)
• ν is the Kinematics velocity of the fluids (m²/s).

OBJECTIVE:

To 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

SOFTWARE USED:

SOLIDWORKS FLOW SIMULATION MODULE.

SPECIMEN DETAILS:

PIPE DIMENSIONS

Diamete : 0.1m

Pipe length : 1m

FLUID DETALIS(WATER):

ρ = 1000 kg/m³

μ = 8.90 × 10⁻⁴ Pa. s

CALCULATIONS:

To find the inlet velocity for the given inlet reylonds number using the formula

s.no	Reynolds number	Inlet Velocity(m/sec)
1	100	0.00178
2	1000	0.0178
3	10000	0.178

BOUNDARY CONDITIONS:

1. One face of the pipe is defined for inet velocity>

2. Another face is defined at static prssure.

3. The surface of the pipe is considered as real wall.

After completion of the modelling the pipe and definining the boundary conditons in flow simulation module, we sholud mesh and run the study to obtain the outputs of velocity profile at 95%, 90% and 85% of the pipe length. To obtain the velocity profile we can use XY plot and CUT plot options in results window.

PROCEDURE

1. Create a cylinder model: size -Dia=120mm, Length = 1meter.

2. Convert to shell of thickness 2mm

3. Draw line probes at 0.95m, 0.9m and at 0.85m from top / inflow.

4.These line probes are created to check velocity, shear stress at this particular sections of the pipe flow.

5.Save as pipe_flow_with_line_probe.sldprt

6.Go to Flow simulation. Create Lids on both inlet and outlet of pipe.

RESULT

.

CONCLUSION:

Simulated the flow through pipe for different Inlet Reynolds number and observed the variation in velocity profile at 95%, 90% and 85% of the pipe length.