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Step 6: Analyze Results

Plot Velocity Vectors

Let's plot the velocity vectors obtained from the FLUENT solution.

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We see that it takes 2-3 mesh cells for the flow to turn. According to inviscid theory, the shock is a discontinuity and the flow should turn instantly. In the FLUENT results, the shock is "smeared" over 2-3 cells. In the discrete equations that FLUENT solves, there are terms that act like viscosity. This introduced viscosity contributes to the smearing. A more thorough explanation would have to go into the details of the numerical solution procedure.

Plot Mach Number Contours

Let's take a look at the Mach number variation in the flowfield.

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We see that the Mach number behind the shockwave is uniform and equal to 2.2. Compare this to the corresponding analytical result.

Plot Pressure Coefficient Contours

Pressure Coefficient is a dimensionless parameter defined by the equationwhere p is the static pressure,

P_ref is the reference pressure, and

q_ref is the reference dynamic pressure defined byThe reference pressure, density, and velocity are defined in the Reference Values panel in Step 5.
Let's set the reference values necessary to calculate the pressure coefficient.

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