Flow over a cylinder
PROJECT NAME: FLOW OVER A CYLINDER
AIM:
- Calculate the baseline case Reynolds number.
- Re = rho*U_inlet*D/mu
- D = cylinder diameter
- mu = dynamic viscosity
- rho = density
- Run a baseline simulation and then calculate the Reynolds number. Then increase the Reynolds number by a factor of 20%, 40%, and 100% then run the transient flow simulation.
PROCEDURE :
STEP 1: Create a cylinder of diameter=5mm,length=100mm.Save the file.
STEP 2: Go to flow simulation and click on wizard.Give the project name.then click External Flow->Time dependent where you give the time of analysis->Add Air As fluid->change the velocity in x axis with respect to reynolds number->Click finish.
STEP 3: Run the Simulation.
STEP 4: Click Results->Cut Plots->XY Plane and create cut plot at the centre of length or half of the cylinder->click on mesh->velocity->click OK.Then we will get the velocity plot of the flow over a cylinder.Foll0w the same procedure for pressure plot but instead of selecting velocity we have to select pressure.
STEP 5:Insert Animation->cllick on animation wizard->give time 10 sec or more->click next and click on scenario->Insert Time->finish->Then adjust the time slots in the below.
CALCULATION:
Diameter=0.01m
Length=0.1m
Density=1.225kg/m^3
Dynamic Viscosity=1.81 X 10^-5 kg/m^3
Case 1: For the baseline simulation Velocity=10m/s.
RE=(Density*velocity*Diameter)/(Dynamic Viscosity)
RE=(1.225*10*0.01)/(1.81*10^-5)
RE=6767.95.
Case 2:Increasing the Reynolds number by 20%
RE=6767.95+(0.2*6767.95)=8121.54
V=(RE*Dynamic Viscosity)/(Density*Diameter)
V=(8121.54*1.81*10^-5)/(1.225*0.01)
V=12 m/s
Case 3:Increasing the Reynolds number by 40%
RE=6767.95+(0.4*6767.95)=9475.13
V=(9475.13*1.81*10^-5)/(1.225*0.01)
V= 14 m/s
Case 4:Increasing the Reynolds number by 100%
RE=6767.95+(1*6767.95)=13535.9
V=(13535.9*1.81*10^-5)/(1.225*0.01)
V=20 m/s
RESULTS:
Case 1:RE=6767.95, V=10 m/s
https://drive.google.com/drive/folders/1dXk_We2u9HrLgcRJuPmcSL5H0lslvKNf?usp=sharing
Case 2: RE=8121.54, V=12 m/s
https://drive.google.com/drive/folders/1HE55UfuTipz5nWGL_R8JNlcs5CU6IIWd?usp=sharing
Case 3:RE=9475.13, V=14 m/s
https://drive.google.com/drive/folders/1A1tnoYF7b4eV8KlxB0gFrmVIoRxSoz7Z?usp=sharing
Case 4:RE=13535.9, V=20 m/s
https://drive.google.com/drive/folders/1UXrlz05rBaqA7kXplTQQAXaZRDgTRr9o?usp=sharing
All 4 cases :
https://drive.google.com/drive/folders/1dXk_We2u9HrLgcRJuPmcSL5H0lslvKNf?usp=sharing