Flow over a cylinder

Flow Over a Cylinder

Aim:

The aim of the project is to run an external flow baseline simulation over a cylinder and then calculating the Reynolds number for every 20, 40 and 100%. A transient simulation has to run and calculate the simulation end time.

Objective:

• Design the cylinder in solidworks and run a flow simulation
• Assign boundary conditions and create plots at various velocities and pressure
• Create animations for every plot.

Introduction

The project study is use for carrying out an external flow baseline simulation to check the various scenarios of flow over cylinder with changes in the percentage of Reynolds number. The flow can be determined whether it is laminar or turbulent with the help of Reynolds number

• Formula for Reynolds number:

Re = rho*V*D/mu

Where,

Re = Reynolds number

V = Flow velocity

D = Diameter

rho = density

mu = dynamic viscosity

• Calculations

Considered parameters:

• Diameter = 0.04m
• Initial velocity = 10m/s
• Density = 1.225 kg/m³
• Dynamic viscosity = 18.14*10^-6 Ns/m²

Substituting the values in the Reynolds formula we get,

Re = 27012.13

Similarly, Reynolds number at 20, 40 and 100% we get the following results

At 20% = Re = 32414.55

At 40% = Re = 37817

At 100% = Re = 54024.26

External flow baseline simulation over a cylinder:

Results:

Velocity plot at 10m/s

Pressure plot at 10m/s

Velocity plot at 12m/s

Pressure plot at 12m/s

Velocity plot at 14m/s

Pressure plot at 14m/s

Velocity plot at 20m/s

Pressure plot at 20m/s

Conclusion:

Therefore, from the plots and calculation we conclude that as the Reynolds number increases the velocity increases, as it is directly proportional to it. The changes in pressure plots is not seen due to the pressure is acting on the front area of the cylinder, which will not change with the change in Reynolds number. The velocity change is seen minor in 20% and 40% while comparing with the base simulation, but there is a huge change in the plotsof the basic simulation and then increasing the velocity by 100%.

Animation plots-

https://drive.google.com/folderview?id=1l-UkPVTPZoaNnqsKtRMDT5K9Uphj0_1X