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Mar 26

Wakesurf wake water flow test results

Drum roll please! So we had hoped to bring you video of the wakesurf water flow through view port in the actual testing environment and when we went to turn the go pro, there was NOTHING. We charged it fully 2 days before, but at the lake site, it was dead. So either we have a faulty battery or we accidentally left it on for the two days. Either way we don’t have video. The only thing we can present is the following picture that shows sort of the wakesurf water flow:

Sequence shots small 268

So first thigs first – do THAT with your center stringered board! Right?! Huge gaping hole in the middle of the board and the composite sandwich still held up, didn’t break upon getting up or while being surfed. Now we know that some folks with malicious and misleading agendas have said otherwise, but you can see for yourself, that’s a really strong and stiff construction and isn’t dependent upon a single stick of wood down the middle for it’s stiffness and strength.

We also have to wonder who will be the first to steal that idea from Flyboy Wakesurf and pump out a production board with a view port. :)  We’ll bring you that result in a future post :)

Back to the wakesurf water flow testing and we’re going to make some broad assertions here that we’ll hopefully go back and test more thoroughly, but also make some statements that are counter to generally accepted premises.

First, there is no real flow backwards. The greatest assumption is that bottom shape in some manner or annother channels or directs water flow across the bottom and out the back of the board past the fins and through channels or concaves.

That just isn’t really true. The single greatest force is UP agianst the bottom of the board. In the picture above, it’s a little hard to see, but the only streamers visible were the gold ones. The purple ones never crossed over the view port. BUT and this is important, the gold ones were PLASTERED up against the bottom of the board. They were literally pushed up against the view port and wouldn’t move regardless of the board movement. There were no eddy’s or changing in direction with the direction of the board. Well, that isn’t quite true, there would be shifts in very straight angular lines after the board changed direction. But it wasn’t from water flow running along the length of the board. It would seem to be from the strength of the water pushing up against the bottom of the board. So the further away from the wake the board got, the more likely the streamers would shift. But they didn’t flow smoothly, it was a single jerky motion to the new alignment.

NOT like water flowing dwn the length of the board.

What is happening, is the wakesurf board is traversing across the length of a column of water flowing UP. Once the water hits the bottom of the board the flow is chaotic. It goes forward, to the sides and towards the back. It also dissipates almost all of it’s energy once it hits the board and is met with the resistance of the board and rider combination. At least at wakesurfing speeds. Perhaps at 30 mph that changes. but at 12 to 15 mphs where we typically wakesurf, the predominant force is upward against the bottom of the board.

There is not real flow backwards, instead it’s like air passing by a car in motion. The car cuts through the air and so the air is stationary, but the car is moving. For the most part, unless it’s really windy, the air is just there not doing much. That is where the analogy separates, because unlike the car, our wakesurf wakes have tremendous power in terms of lifting forces. We capture those lifting forces and balance ourselves on them as we wakesurf.

As we slide across the surface of the wake, the water from the lifting forces pushes up and against the bottom of the board with more force than the water flowing backwards. So channels or anything else that is designed to aid water flow out the back, doesn’t do that. Doesn’t mean that they don;t work, just that they don’t flow water out the back of a board. The water flowing UPWARD pushing against the bottom of the wakesurf board is stronger and really faster than the water that sort of disperses after it hits the bottom of the wakesurf board.

Remember the really poor quality iPhone video? Where the streamers sort of lazily drifted backwards as the board moved? The streamers were attached to the stationary water below the board. That doesn’t exist during the actual act of wakesurfing. The streamers are plastered against the bottom surface of the wakesurf board and THAT, dear friends, is the water flow in wakesurfing.

The design criteria then for bottom shapes, really needs to focus on capturing the flow UPWARD, and then minimizing drag and attachment to that upward flow. Our forward motion, across the water flow upward, redirects that flow off at 90 degree angles, but also produces lift.

Hopefully we’ll have some additional theories we can glaen from that and we’ll talk about them in teh future!

Thanks so much for following along and we do aplogize for the lack of video as we tested the see-thru wakesurf board.

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