Fan blade orientation?

[Patrick Wong]

Hi Rob,

Thanks for providing a very detailed writeup about your work.

The Toyota repair manual is silent regarding the correct fan rotation direction. The exploded parts diagram shows that one fan has seven blades while the other has five blades, but you have to look closely to note this. Prior to reading your posts, I had assumed that the two fans were the same and rotated in the same direction.

[kohnen]

Yikes! One fan goes to the left and the other to the right! Is there some sound technical reason for Toyota to have done this or is this political correctness run amuk?!?!



Seriously, first place award for troubleshooting above and beyond the call of duty!

[snijd]

I think it may have something to do with the fact that Japanese fighter pilots held the P-38 Lightning in such high regard in WWII. The P-38, of course, had counter-rotating propellers, but in the opposite directions of the fans in the Prius. You think this is far fetched?

Rob the docent at the Seattle Museum of Flight

[JHSmith]

Originally Posted by kohnen

Yikes! One fan goes to the left and the other to the right! Is there some sound technical reason for Toyota to have done this or is this political correctness run amuk?!?!



Seriously, first place award for troubleshooting above and beyond the call of duty!

You surprise me!

Do you ever realize that on multi-engine prop planes, they have counter-rotating engines / props to decrease torque so the planes won't spiral out control?

Well, Toyota, in their infinite wisdom, used the same engineering analysis and made counter-rotating fans?

Word has it, they will follow suit in the 2010, and have the front wheels rotate opposite of the rear wheels!