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Old 05-11-2020, 11:00 PM   #109 (permalink)
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Originally Posted by M_a_t_t View Post
Why don't you like it? This is one of the few aerodynamics books I do have.
It's just distressingly vague and unhelpful.

Take Pages 128, Fig 5.15. Cutting off the tail of the aerofoil does not increase drag only if separation was already occurring at the marked point. The two paragraphs that purport to describe what is going on are just terrible. For example, "the goal of bobtailing is to keep suction in the wake small" is wrong. The goal of bobtailing, as shown in Fig 5.15, is to not bother extending the car past the natural separation point. As the next para says, in each case drag will be the same - a neat contradiction in just two successive paragraphs.

It's all like that. A mishmash of stuff, with very few references made to published papers on real cars (and so having real life examples).

I think a much better overview is provided by Barnard, Road Vehicle Aerodynamic Design.
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