Artificial reef - airwave

simba's picture
simba started the topic in Saturday, 11 Aug 2018 at 6:39pm
simba's picture
simba's picture
simba commented Saturday, 11 Aug 2018 at 6:39pm

.

simba

spuddyjack's picture
spuddyjack's picture
spuddyjack commented Saturday, 11 Aug 2018 at 7:35pm

Really interesting read Simba. There seems to have been considerable research done hitherto. This would certainly cut the lunch of the wave pool wet dream brigade - at least to some extent. Would be marvelous if the inaugural project worked well and encouraged more councils to get on board. Victor Harbor council (SA) should be approached to address the less than mediocre Middleton-Pt Eliot stretch - that poor bloody demographic of surfers need a decent break - literally and metaphorically. No doubt there are countless possibilities around the globe. Hope the crowd funding comes together quickly.

Stay salty

Nick Bone's picture
Nick Bone's picture
Nick Bone commented Sunday, 12 Aug 2018 at 2:00pm

I get excited about a project like this, as there would be a excellent beach at home for this but it makes we wonder that if it did work as well as they say i.e a straight 6ft swell we get rather regularly, how crowded it would get. What i mean is, the places that these would suit would also get extremely busy as there wasnt much option to begin with?

indo-dreaming's picture
indo-dreaming's picture
indo-dreaming commented Sunday, 12 Aug 2018 at 3:04pm

Great if they can get it up and going and like to see it succeed and i think we have talked about similar/same idea here somewhere.

But skeptical it will work that well.

1. Seems its full with sand but also air? any air will create buoyancy making it less stable and easier to get moved around by waves and currents.

2. We already know from the Gold Coast sand bags objects like big sand bags just sink if sitting on sand as the water/currents/wave action just undermines the bags.

On a solid bottom like coffee rock, could be more successful though.

blindboy's picture
blindboy's picture
blindboy commented Sunday, 12 Aug 2018 at 2:43pm

I agree Indo. Having seen the size of the boulders moved around, I'm struggling to imagine how it could be secured well enough to survive the kind of storm conditions we get on the east coast.

simba's picture
simba's picture
simba commented Saturday, 18 Aug 2018 at 6:11pm
Eugene Green's picture
Eugene Green's picture
Eugene Green commented Saturday, 18 Aug 2018 at 10:54pm

Bunbury? That’ll be the second time an attempt at making an artificial reef in WA is unsuccessful due to a lack of swell in the chosen area. More money down the drain and will make it harder to fund any future plans for man made waves at better suited sites.

stunet's picture
stunet's picture
stunet commented Sunday, 19 Aug 2018 at 8:01am

Not a chance in the world it can work.

spuddyjack's picture
spuddyjack's picture
spuddyjack commented Sunday, 19 Aug 2018 at 10:12am

Why Stu? Poor overall bathymetric factors for the project at Bunbury or poor design or both? Please elaborate.

Stay salty

lampy's picture
lampy's picture
lampy commented Sunday, 19 Aug 2018 at 10:44am

Just doing a few basic calculations, If you submerge 300 m^3(just a guess of how large the dome would be and the volume) of air under seawater the force to hold it on the seabed is 307.5 tons. That's a lot of force to keep on the seabed without taking into account the swell force which will deform the dome and create localized elevated forces.
He is stating he will use 12 helical sand anchors. They are going to have to be very big to hold down 307 tonnes

lampy's picture
lampy's picture
lampy commented Sunday, 19 Aug 2018 at 10:45am

Wonder if he has done some scale models? doesn't seem to be much info on his testing

simba's picture
simba's picture
simba commented Sunday, 19 Aug 2018 at 11:14am

It might possibly be filled completely with sand.........whether thats enough to hold it down is the question.

simba

Craig's picture
Craig's picture
Craig commented Sunday, 19 Aug 2018 at 11:33am

No way that will stay attached to the ocean floor during a big storm.

blindboy's picture
blindboy's picture
blindboy commented Sunday, 19 Aug 2018 at 12:50pm

....... it could be a thoroughly deflating experience!

stunet's picture
stunet's picture
stunet commented Sunday, 19 Aug 2018 at 4:37pm

@Spuddy,

One of the biggest misconceptions about wave mechanics is that wave shape is solely a product of the bathymetry below the wave. It's not. Equally as important, and very often overlooked, is the bottom topography immediately offshore from the wave - otherwise known as the 'run up'. The run up primes the wave for breaking, stands it up, focusses energy etc.

The importance of the run up increases as the wave period increases, because the swell feels the bottom earlier. Put a structure on the bottom with no run up, in a zone of long-period swells, and you'll get an undersucking, unsurfable surge.

So perhaps the intention is to have sand build up around the structure and create a run up? However, sand wont lay against something that's moving, even a few millimetres of movement, so it simply won't happen.

I like the out-of-the-box thinking, however, without sounding too harsh, the Airwave is destined for the Great Pacific Plastic Patch. I hope it doesn't sink all goodwill for artificial reefs 'cos there are some good ideas out there.

spuddyjack's picture
spuddyjack's picture
spuddyjack commented Sunday, 19 Aug 2018 at 5:01pm

@ Stu,

Many thanks for that cogent explanation Stu. I had given no thought to the bottom topography run up factor whatsoever. Hopefully other good ideas will emerge to factor this in accordingly in future designs.
Cheers,
Spuddy

Stay salty

tubeshooter's picture
tubeshooter's picture
tubeshooter commented Sunday, 19 Aug 2018 at 6:07pm

Scale modelling is one thing , but that is done in static environments that don't reflect the nature of the areas they would be placed, or the volumes and forces that the structure would be up against. Wet sand is far from solid and anchoring anything of any mass to it will take more than a few sand anchors. The opposing forces between the buoyancy of the air and the anchoring system will be in constant opposition to each other and will create many stress points. Highly skeptical.

udo's picture
udo's picture
udo commented Sunday, 19 Aug 2018 at 6:39pm

This is this blokes second crowdfund / kickstarter try for a Artificial Reef ?

Adrenochrome

tubeshooter's picture
tubeshooter's picture
tubeshooter commented Sunday, 19 Aug 2018 at 7:07pm

I wonder if he's called Dirk yet. I bet he hasn't factored in the little things , like councils will need full environmental paperwork cleared by seagrass and sand worm experts, sand movement problems leading to potential erosion, unretrievable broken bags half swallowed by sand, community opposition , commercial fishing {beach haulers}, hippies , , ,,, need I go on?
Tell him he's dreaming.

David Brown's picture
David Brown's picture
David Brown commented Monday, 20 Aug 2018 at 3:06pm

Nice idea!
It will be great for both adults and children to enjoy their surfing lives.

David Brown
shaka-surf.com

andrew-pitt's picture
andrew-pitt's picture
andrew-pitt commented Monday, 20 Aug 2018 at 10:52pm

Troy - best wishes - hope it gets up. Tweak it, you'll figure it out.
Found the 2014 Kickstarter campaign.
Anybody find the link for the 2018 campaign?

andrew-pitt's picture
andrew-pitt's picture
andrew-pitt commented Tuesday, 21 Aug 2018 at 3:08pm

The 2018 Kickstarter link is here...
www.kickstarter.com/projects/airwavesurfreefs/airwave-the-worlds-first-i...

Stu - are you going to run a story on this?

There's one key reason why every surfer should back this project, via Kickstarter.

frog's picture
frog's picture
frog commented Tuesday, 21 Aug 2018 at 7:57pm

Some merit if it is placed to support an existing sort of semi closeout bank. If it creates a peak and take off point to lead into existing angle where some peel and some do not. But on its own in a real closeout it might end up as a very brief takeoff followed by a major slamming shorebreak. The ability of a structure to alter the angle of a wave is determined by its length relative to wavelength. The structure needs to be multiples of the wavelength otherwise it surges past with no time to shift. The design should be long drawn out eclipse pointed out to sea, not a circle. The smaller it is the less chance it wiil work. Any good reef or even small bombie that creates a good wave is much larger than meets the eye.
But I think the pluses are using sand to weight it and air to add easy volume and it being soft and mobile. The goal is the great but I would need to see videos of the testing to see if the round design would work better than my current view.

Frogg