A study of water flow over a flat bottom in 3 stanzas

High speed rush on 6’0x 23"x2 1/2" thin railed bamboo EPS

The push

The lift

 

The effect

How did you get the shots? Interesting how little board is actually in the water.

Huck,

The pics are blown up crops from part of a sequence of me at Arugam Bay, Sri Lanka last month taken by Down the Line Photography

A lot of what we discuss about water flow here on Sways can be seen in the shots. The split of the water and flow across the botton in the first shot, the water beading off in the second shot, and one fin and an bit of rail holding in in the third shot.

Fascinating. Weird how the water hits the fin out of the water in the third shot. Seems to be flowing from the direction of the board outward and hiting the inside flat face of the fin. The obvious takeaway is…I dont know. 

All the best

Wow, we need more of those pictures!

Thanks for sharing

That’s cool. I’d love to see what the back half of the board is doing in relation to those front shots.

great angle

Red Boards, you’re going to have to go back to Sri Lanka for more photos.

WTF.  Pics don’t show,  just a “waiting for photobucket” message in the loading window.

It’s a tough job, but someone has to do it.

The water is deffinatelly sticking as it runs across the bottom. Great to see this.

 The addition of a 3/4 length quad concaves with linear spines would have to give life/lift to the board, that would explain the floating feeling from such bottom designs.

Tomo’s got a 1000 team riders to test his boards, I got about a handful haha. There onto something at Firewire.

 

What do you make of the water hitting that back fin in the third pic?

The more cant that fin has the easier that water will deflect off it.

I think there’s still water flow diagonally across the bottom for the board from about midway where the rail is latched into the wave face. It’s all water release in the 3rd pic, so the water’s moving over the rear half of the stringer curve and hitting the outside fin.

The rear fin looks to have a bow wave

Here’s the sequence:

 

I always found these videos pretty facinating on plane on edge you get a pretty good idea how the water moves. 

https://vimeo.com/87995258

 

https://vimeo.com/151486023

 

 

 

 

 

 

That first video is interesting. Nice to see the change in water flows as weight is applied.

BUT flat water with board under power so not directly applicable to waves and unpowered boards.