Quote:
Originally Posted by kach22i
I'm perplexed by the increase the cross-sectional area compared to the typical pencil shaped body.
Every time I draw a hump over a vehicle cabin that is higher than needed for headroom it gets shot down.
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It's the whole 'laminar' trick.
The boundary layer will remain laminar as long as pressure is lower in the flow direction.
Once the first ( only) minimum pressure ( maximum local velocity ) is encountered, after that, in the lee of the maximum cross-section the pressure increases as the cross-section contracts, and the laminar boundary layer 'jumps' to turbulent boundary layer, with terrific, comparative viscous shearing losses.
For us, typically submerged in Earth's own turbulent boundary layer, we can never have a laminar boundary layer, on account of Reynolds number effects. At 41,000-feet it's different.