Biomimicry

[cons]

Check this out, a new wind turbine blade based off a humpback whale fin with 33% less drag due to the bumps on the leading edge.

WhalePower Fan Test | Whalepower

Janine Benyus: Biomimicry in action | Video on TED.com

[Varn]

I passed a truck hauling a wind turbine blade yesterday. It was smooth on the ends but it had a hundred small fins probably an inch high on the surface. Must help?

[winkosmosis]

Originally Posted by Varn

I passed a truck hauling a wind turbine blade yesterday. It was smooth on the ends but it had a hundred small fins probably an inch high on the surface. Must help?

Fins stuck to the blade?? Maybe if I put them all over my Jeep I'll get 30mpg

[euromodder]

Originally Posted by cons

Check this out, a new wind turbine blade based off a humpback whale fin with 33% less drag due to the bumps on the leading edge.

Amazing stuff !
I'd expect to see this on more wings and fans in the coming years if it's really that efficient.
Bye-bye winglets & strakes, no need for them if there's no crossflow anymore.

In WW2, fitting a small block of wood on the leading edge of a Vought F4U Corsair's wing cured its rather vicious stall characteristics.
Shame nobody thought of fitting more blocks spaced all along the LE ...

[winkosmosis]

I for one don't like this. They may be more efficient but the lumpy edge is ugly!! I just hope cars don't end up with weird lumps on leading edges.

[Varn]

Form follows function.
Perhaps it would be good for making yourself more invisible to radar. Like the F-117.

Originally Posted by winkosmosis

I for one don't like this. They may be more efficient but the lumpy edge is ugly!! I just hope cars don't end up with weird lumps on leading edges.

[wyatt]

This would be a neat weekend experiment, bio-ceiling fan! If only one could be sure that the blades were balanced ahead of time...

[Patrick]

Originally Posted by cons

Check this out, a new wind turbine blade based off a humpback whale fin with 33% less drag due to the bumps on the leading edge.

WhalePower Fan Test | Whalepower

Janine Benyus: Biomimicry in action | Video on TED.com

Their video sure didn't match their commentary. The airflow was doing the exact same thing where they had the tubercles as where there were none.

Compare to this fan: FSEC-CR-1059-99

[RobertSmalls]

Nature produces some things that are highly optimized by tens of thousands of generations of trial-and-error. But unless you are building a whale, nature's solution may not be an optimal one.

Biomimetics is a source of some inspiration for novel innovations, but it also spawns loads and loads of gimmicky products. I would file dimpled/tuberculated fan blades under "gimmick". Dimpled fans have been around for a while, but they don't appear to offer any advantage, at least in small (4-12cm) fan and desk fan applications.

[RobertSmalls]

"Figure 7. Danny Parker checks fan rpm at high speed."

It looks like he's using an optical device to measure RPM, but you can measure fan speed with a microphone attached to a PC. Look for the dominant frequency in the fan's acoustic signature, and divide by the number of blades to get revolutions per second.