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The other properties are also functions of temperature. However, we'll use constant values equal to the average values over temperature range obtained in the experiment. Enter the following constant values:


Cp (Specific Heat) (j/kg-k): 1005
Thermal Conductivity (w/m-k): 0.0266
Viscosity (kg/m-s): 1.787e-5
Molecular Weight (kg/kgmol): 28.97 
 
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Boundary Conditions > Operating Conditions...

Enter 98338.2 under Operating Pressure and click OK.

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Next we will specify the boundary condition for the centerline.

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Click Edit... to set up the correct inlet parameters. The Velocity Inlet window pops up. Enter 30.06 next to Velocity Magnitude (m/s). Under Turbulence, select the specification method to be Intensity and Viscosity Ratio.

 Use the default values for Turbulent Intensity (5%) and Turbulent Viscosity Ratio (10). These are plausible guess values for the turbulence level at the inlet. FLUENT will calculate k and epsilon at the inlet from these values and use them as boundary conditions for the k and epsilon equations.  The results should not be sensitive to these inputs since most of the turbulence is generated in the boundary layers (ideally, you should check the sensitivity of your calculation to this setting). 

 

 Now click on Thermal tab and enter 298.15K for Temperature. Click OK to close the window.


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Finally, set up the outlet boundary condition:
Boundary Conditions > Outlet
FLUENT selects the pressure-outlet boundary type and its guess turns out to be right. 

Click Edit... to specify the gauge pressure at the outlet.

Enter -1112.3 for Gauge Pressure and click Ok. (From experiment, measured outlet pressure is 97225.9 Pa. Corresponding gauge pressure = 97225.9 Pa - operating pressure = -1112.3 Pa)

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