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Old 05-14-2009, 12:40 AM   #9 (permalink)
Ernie Rogers
Ernie Rogers
 
Join Date: Feb 2008
Location: Pleasant Grove, Utah
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Hi, Tas,

You aren't facing the question. Do you have a source for drag coefficients of bodies of revolution in incompressible flow and high Reynolds numbers?

Access to a CFD program should allow calculation of a Cd, but that's more work than I would expect.

I calculated the Reynolds number:

Sea level
200 mph
35 ft long ------> Re = 65.5 million

Ernie

Quote:
Originally Posted by tasdrouille View Post
Ernie, you got your Cd figure wrong for sure. Maybe you meant CdA, since you mentioned frontal area, but even then 0.02 figure does not seem right.

Honestly, what's wrong with trains? I traveled to Italy last year, taking the train for more or less 200 miles everyday. There were trains every 15 minutes during peak hours and those things travel up to 100 mph with no traffic! And it was insanely cheap!
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