Why does my 1 meter long streamlined body at 0 AOA have 0 pressure drag?

Using SimScale Fluid Flow / CFD
1

Can anyone help me understand why this 1 meter long streamlined body:

Body-v3b
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seems to have 0 pressure drag (X-direction) at ~34 meters/sec?

Here is a link to my sim run that shows this.

Here is the convergence plot:

Body-zeropressuredrag-convergence
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Here is the force plot of the right half of the left/right symmetrical body which shows the strange 0 value of pressure force X (pressure drag).:

Body-zeropressuredrag-plot
Body-zeropressuredrag-plot1299×839 52.4 KB

Also, we can see that my project predicts that Pressure ForceX and Viscous ForceX add up to only ~1N

But if we do a napkin calculation assuming a Drag Coefficient of 0.1 (just an educated ballpark number :wink: ) for this body we might expect to see 2.5N of drag.

image
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I think I have applied good principles in meshing and simulation parameters, have I missed something?

Thanks,
Dale