Quote:
Originally Posted by aerohead
Once attached flow is achieved, no additional softening will result in additional drag reduction. By definition, the flow is 'saturated'.
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Hmmm... that doesn't jibe with what I know about aerofoils on planes. Longer, thinner aerofoils do reduce drag, up until skin friction begins to dominate. However, real engineering is often about tradeoffs, in material, size, etc. That's why truncated aerofoils are often used; they are a good balance between weight and performance.
Quote:
Originally Posted by aerohead
I agree about cooling system drag, but that wasn't the topic.
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Hehe. Well, that might be what you were thinking, but it's not what I was thinking. I include everything at the front of the car to be part of the nose, including the radiator and wheels.
Quote:
Originally Posted by aerohead
Heat exchangers are designed for 100% turbulent flow, to achieve optimum heat rejection.
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We can also improve thermal exchange by slowing the flow, giving the air mass more time to transfer heat.
Quote:
Originally Posted by aerohead
I'm going to call you out on the 20% mpg improvement due to a cooling drag reduction.
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Oh ho! The race is on! Here's my prediction about how the 20% fuel economy increase is going to breakdown:
~3% Nose re-shaping
~5% Air Curtain
12%+ Radiator rerouting (smaller inlet, ducting, etc.)
I agree with you that (sadly) limited space makes the outlet ducting unfeasible. So I'm going to focus on the inlet duct, which there will be plenty of space for once I extend the nose by 8"+. No change in the location of the radiator.
So... would you be interested in a wager whether I can achieve that? I'm predicting that it will be the +8 mpg from 60-something-ish mpg to just over 70. I'm particularly fond of gentlemen's wagers that involves eating crow. (coughs out old feathers).
