Non-Professional Photos of 2010 Prius Thread.

Those Toyota logos don't really glow blue do they? That wouldn't be legal in the UK, at least on the rear. And I'm sure lots of other places would take a dim view.

 

No, it's just paint and lighting. Right now it's a styling debate between Toyota U.S. and Japan. Japan thinks it's cool, while the U.S. thinks it won't fly.

Tom

 

These pictures make the Prius better looking (from front) than ones I've seen previously.

 

As the top of the car has a curved profile like the top of an aircraft wing and the bottom of the car is mostly flat overall the car performs like an aircraft wing which is too short. Over all the car creates lift not down-force.

 

I disagree - the windshield does not produce downforce because it is not acting alone. If you detached your windshield and let it fly, then perhaps. You have to look at the cross-section shape of the whole vehicle. Your hand out the window feels an upforce or downforce based upon its orientation because it relatively flat on both sides.

Yes, I completely agree. The shape of the Prius creates lift, not downforce. That lift is nothing to worry about, though, as the "wing" is too stubby to even come close to overcoming the downforce of gravity.

 

One would have to assume that if an upward sloping surface creates down-force then aircraft would always nose dive as some part of the wing creates lift, and only the rear part is left if the front is busy making down-force.

I saw the capitulation, I just wanted to say this.

 

But what if you drive backward?

Tom

 

You would look stupid on the freeway!

 

One of my friends drove home backward from a bar. In his intoxicated state, he somehow decided it was easier to control the car backing up and looking in the mirror. I have no idea what blind luck saved him that night.

Tom

 

Also agree with Pat. In a smoke tunnel you could probably see 2 rolling vortices coming off the right and left sides of the car, representing the tendency of the air flowing along the sides to roll into the low pressure zone on top of the car. The rear spoiler helps to suppress those I would think.

It's all about boundary-layer control, and boundary layers come in two forms; laminar and turbulent. Laminar flow generally exists for short distances over any surface, prior to transitioning to turbulent flow. The secret then is to re-energize the turbulent boundary layer at various points to prevent complete flow separation (which is what happens when an airplane wing stalls). It is flow separation that creates additional parasite drag; the form (or pressure) drag cannot be avoided.

The NYT article quoted is an excellent summary.

 

Excellent pictures, Rick. I did note that Toyota retained the crankshaft belt pulley on the G3, even though it no longer drives any belt.

Any idea why they didn't leave it off altogether? Maybe the same basic engine is used in other models that do retain belt drives.

 

Not all mechanics are ignorant, ask Galaxee's DH. I'm also a mechanic but that supports what you say.

 

The chief engineer said it was used as a vibration damper. The damper could be moved inside of the engine, but that would take more work.

Tom

 

Yes that makes sense, in a torsional way, simply due to the rotational inertia of the pulley. There's probably a host of other practical reasons too.

 

We will, with your blessing agree to disagree.
A car shaped like a Prius driven at high speed will create lift overall, no time to argue the point.
Front air dams and rear spoilers are measures to reduce or counter this lift.

 

Sorry to disagree, but as an engineer who has derived the Bernoulli Effect from the basic laws of thermodynamics, I can tell you with certainty that you are wrong. The length to width ratio of a lifting foil is called the aspect ratio. A higher aspect ratio is more efficient, but low aspect airfoils still produce lift. If you want some practical examples, go back to the NASA site and take a look at lifting body aircraft.

Tom