artificial wavepool design

General Discussion
1

Well, this has something to do with surfing and I could need some help :slight_smile:

I want to built a new type of Wavepool…(maybe I’ll call it The Liquid Stadion, haha).

Maybe some of you know www.tube6.de , it’s a structure that is sank into a river and allows, by filling tubes with water, to alter the shape and size of the wave (shoulder, tube, 1-4m)

Tere is no such wave till now.

I guess it is very hard to get the permission to built thinks into rivers, especially in Europe.

Here comes my idea:

Why not pump water in a cycle. We used to do that in round swimmingpools, just speed up the water by running circles and once it is running it keeps the momentum for quite some time.

If you would built a ~1km long pool in the form of a ring or oval and integrate tube6 oder a similar feature you could produce surf anywhere…

Not anywhere…but at least where people are known to built insane, moneywasting, megastructures and machines (like skiing venues) …Dubai comes to my mind spontaniously…I mean…when you can built 1000miles of artificial coastline…what is one artificial gigantic wave compared to that?

Another big toy to pimp Dubai…

Now I have to figure out a way to built a model.

I can built anything in CAD but I want a 1:20 or 1:25 scale realworldmodel.

Maybe fiberglass…

I have only worked with Epoxy so far…never Polyesther and Epoxy is too pricey for that task.

Maybe a gipsum model with coating…or paper and glue with coating?

What is that grey stuff models are built of sometimes?

Foam and fiberglass?

what do you think? You may declare me officially insane now :slight_smile:

graphic from Tube6.de

2

The Grey stuff models are made of is generally high density PU foam.

there’s also a material called Cybatool (I believe Bayer makes it) that carves like wood but without the fiber.

both materials are quite expensive.

you might be able to get away with just shaping foam and sealing it with something, after all I doubt you’ll be putting a lot of stress on the structure unless you have a thin lip ( that you don’t necessarily need)

as for pumping the water, it seems like their solution is much better: use water that’s already moving, no running cost and lower energy/environmental impact.

although this might be hard in dubai, but I bet people want to surf in Vienna too

BTW, I don’t think you actually need the structure to come over like a roof, like you show in your CAD. If the wave gets steeper than a certain angle, it will naturally start pitching (I think)

d

3

Thank you for the reply.

The graphic is just a wave actually not the structure. The structure should be moveable (inflateable with water…do you call something inflateable in english when you pump water in it?)

I thought these models where made off textile enforced concrete (as it was used for roofing, they changed the aspesto part to organical fibers though).

The pumping is one of the main features because suitable waterfeatures are not available everywhere.

Here in Vienna Rivers and Water are one off the tougest places to built something in…it would be so hard to get permitment to use a river for anything that it would fail the thing in the beginning. This is mostly due anual floods and because most rivers are already full with electric power plants.

Rivers change waterlevels yearround.

And Tube6 is already a feature for the river.

There are some ideas how to speed up the water. with waterjetturbines or maybe big paddels that run wounds inside the ring and push water out of slots. Water could run over in the tubine system through overflow, like in a swimmingpool, into a reservoir, so that nowbody gets sucked into turbines, slots or holes.

The water flows in a flat ring actually, only where the wave comes in it gets shallower (maybe narrower too) thus speeding up the flow, the form of the ground will then form the wave that should be there already.

I hope to find some hydro engeneere soon that can help me do the calc (maybe it gets my final thesis for M.A. degree too) and say if it would use more energy than a waveloch machine.

It should be more energy efficient than a normal wavepool though where all the energy of the wave is gone after every wave and has to be produced again for the next one + it is a wave runnning infinite, it can change its shape, it can be switched off for security (not a bad selling point for the US :wink: haha) and maintainance (try this in a river).

I have to admit the whole concept is a littel adventurous but fun…and who knows what it will develope into :wink:

these guys built there own wavepool :slight_smile: check it out.

4

check out these guys - http://www.surfthering.com/ - they used to have vids of their model in action. It’s the best design for a man-made wave pool I’ve seen so far.

Their pool is designed to be a doghnut shaped ring that’s about 500’ in diameter - with an 80’ wide dry center section. The bottom is shallow on the inside of the ring and gets deeper on the outside. The perimeter is lined with blocks - like dominos - that undulate and create waves that go around the ring - either all rights or all lefts. There are something like 16 continuous waves that are always going. You can paddle in to any one of the waves at any point in the ring. If you loose the wave you can catch the next one.

One of the best parts of this setup is you can ride a single wave until your legs fall off, and there’s room for 15 of your friends to ride at the same time. No waiting. Also it seems like it would use less energy than a pool that requires tanks to fill or pressure to build. Also unlike the Flowrider or a standing wave in a river, you’re moving like you would be in the wild.

I don’t know if these guys are getting any closer to building a ring for real, but I’d like to try one out.

5

They’ve taken down most of their web pages.

Maybe patent issues or maybe they have a backer and are about to start construction.

Anyway, not all the content is gone.

More:

http://www.surfthering.com/images/abarrel2.jpg

http://www.surfthering.com/images/alongwall.jpg

http://www.surfthering.com/images/alongwall2.jpg

http://www.surfthering.com/images/alongwall3.jpg

http://www.surfthering.com/images/alongwall5.jpg

http://www.surfthering.com/images/athreewaves2.jpg

6

Wow…thank you so much, i didn`t know theis design.

I thought I have already searched the whole web for ring formed wavepooldesigns for years!

Can you remember some more details? They have nothing online anymore :frowning:

But I am not so sure if it needs less energie than my proposed design, which could also feature more waves, lefts and right, tubes and nonbreaking greens at the same time.

Please correct me if I am thinking wrong, I am no hydrodynamic too.

Im my system I only need to bring in as much power as is used by the waves, friction in the system and what is used to keep the water at a certain speed. Where I don`t necessarily have to create a breaking wave…a rideable 3m shoulder would be ok for a lot of people, a tube would need more energy…bowls and A-Frames could be possible. Just ad another hydraulic structure (which can be designed very accurate in small test channels)

They keep the system running by never stopping to create the same wave…but the power of the wave is ultimately lost when it breaks.

Waveforms and sizes could also be a challenge. When the waves get bigger they would need to reduce riders.

At my local waterskilift they run 8 people at 28km/h in the round and only two when they crank it up at 55km/h.

Can you remeber how big they wanted the waves to create? To modify the shape they would have to alter the whole inner “coastline” which would also mean changing the whole bottom in some cases.

The most interesting part for me would be speeding up the channel by using the undulating effect. I have thought of it before but I guess it would create to much impulses to the sides. Pumps could speed up the water from anywhere in the pool. I am also concerned about the riders safety…I am an avid WW-kayer and have a good feeling for the power of stong currents and streams.

I am not sure if anybody on this board has talked about this topic before but technicians (people who worked on the tube6 dynamics…) have figured out that the dynamic of ocean waves is very similar to river waves, only that the ocean wave moves relative to the ocean surface and changes shape on that move. On the river the wave is alsmost static and the only difference is the missing wind in your face (the scary part is that when it is a hole it might hold you down for some minutes…) Some details like backwash can be very different when the wave hits the shore but are not needed to create a perfect tubing wave (like you don`t have a bouncing wave on reefwaves with no beach to bounce for another 3km)

So you are moving like in the wild relative to the wave…though not relative to the bottom and the air surrounding you…but minus the paddle out also :wink:

…and your friends can photograph you from the bridge over the wave…or through the big glass window on the outside ringwall…or measure the high of you airs…OK, OK…now I am trying to sell it to you :wink: kicking already?

this is an older Design for a WhiteWater-canal

7
Quote:

They’ve taken down most of their web pages.

Maybe patent issues or maybe they have a backer and are about to start construction.

Anyway, not all the content is gone.

Ohhhh…cool

thank you doug

8

Most welcome.

Sometimes it seems as if I live to Google-hack :smiley:

9

Hi there.

I am tinkering with my pool ideas again.

have done some new renderings.

http://85.124.199.50/welleneu/

These are just new visual studies but I am working on another little different structure right now.

The new model will look like this.

The water is pumped on a completly flat oval where the pumps stick out of the bottom, rounded on the back so that a swimmer wont get hurt.

Pumps are locatet right in front of the wave creating structure (which is a shifting reef that can be modified while the wave is running to create rides with sections and simulate a wave from the ocean.).

These pumps speed up the water like discribed in the original design above.

The strucure is narrower and a little above the flat oval to concentrate the flow on the artificial reef.

Waterdepth is controlled by grids or grills around the pool where water can flow in the pump sump (well…I hope that is the correct word…I mean the place where the water is collected to pump out again).

I wonder if this is the easier methode of creating a wave compared to the http://www.surfparks.com / www.asrltd.co.nz approach?

I also wonder which methode of creating waves is more energie efficient?

Still searching for somebody that can work on the hydraulic part…I don`t want to start building models before I get some possitive feedback.

Any input, any ideas?

10

I personally would find a machine centre that can machine timber for you and have them CNC machine it all out of Jelutong timber off your cad (either the wave and track, or just the wave and build the track out of something else?). Hand sand to 80grit (jelutong is excellent to work with - this will be easy) to get rid of any machine grooves and seal the timber with Duratec’s timber sealer - another light sand and spray then spray with duratec sanding primer and finish by hand sanding working from 100grit down to 180, then 250 (you can take out all the high and low spots in this step and re-spray if needed) when you have it “true” smooth with 300grit then spray in duratec surface primer and polish to a gloss (this is now a timber buck or plug and can be used to take a master mould from if you want so that if it gets dammaged its easy to make another one)… then plumb it, seal the plumbing with silicone (if you dont plan to paint it) or sikaflex and hey presto… a model…

lots of elbow work but if done properly will last forever and be a functional model that, with a little prep, can be used to take tools from if you need more models for some reason down the track…

cheers,

riff

11

I am not so much worried about building the pool model but more about the design aspect of the project.

Do you think this is even worth doing it.

Nobody seems to be interested in that kind of pool.

The wave would behave exactly like the wave in the ocean but be infinitly.

One flaw might be that not more than one person can surf simultaniously.

You could have more waves in one pool though.

This time management issue would be much like on a flowrider but with real programmable waves.

12

Hi there.

I am still playing around…

There is not somebody here by chance that works with computational-fluid-dynamics?

here is my newest picture…

I worked all night on that model.

http://85.124.199.50/render/welle/render05.jpg

all other pics are found here.

http://85.124.199.50/welleneu/

an this one is a 360x360° Quicktime Panorama from the pit where you can watch the wave from the side through the glass.

http://85.124.199.50/render/welle/wavebunker.mov

The glass would break, I know…

Some day I will surf that thing…

13

hi marcus !

the idea of the movement and forces in a whilpool, in which you rotate the water fastly, has more to it than just energy-efficiency in my opinion.

one thing is to make a wave close to the natural scene but perpetual. the other thing would be to emphasis on possibilities in the system which go beyond the natural setting. the image i see, inspired by your ideas, is rather that of a much smaller arena, let´s say maximum diameter 20 yards with rotating waters so fast, that they angle about 20% to horizontal or more. to just turn around would make you sick after a short while, but - here it comes - you surf a permanent wave at fixed points, which makes you feel ordinary gravity in vertical direction again. there must be interesting angles to the waterflow direction in which you can build the wave alongside the “slopes”. imagine the force momentums you will get, when suddenly parking yourself in the wave from full rotation, going high, going low, taking off and meeting the point again a short round later. this would be also suitable for using boogieboards and playboatkayaks.

what yer say?

greetings from northwest - d.

14

This is a much more technical challenge than my wavepool I fear. creating a 20% steep surface is one challenge…then creating waves that are surfable on that tilted surface the next problem.

Can you make a drawing …by hand or something and draw some vectors that show intented forces?

My starting point also was a circular pool with some kind of whirl in it (verdammt…was heisst Strudel schon wieder auf Englisch… whirlpool würde die Übersetzung sagen…oder swirl…ach…wir sollten sowieso Deutsch reden). The whish and need to controll the thing has lead to the oval pool. It is still not proven that the pool can be controlled at the inner circle…to reduce turbulences it will be good to reduce the difference between outer curve and inner banks as much as possibel…

geh…schreib mir doch eine email wenn du Lust hast…wenn dann bauen wir das doch eh für uns armen Binnenländler und alle die keinen Zugang zu Wellen haben und nicht für die Amis :slight_smile:

15

hi marcus!

i did some calculating today in order to have rather solid figures for imagination. but first let me give some explainations on the stuff i thought about. you asked me to draw scetches, but i was to lazy for now. the first problem you marked is that of different speeds and resulting turbulence in the rotating waterbody.

as you say, there are different lengths of the outer and inner circles. a little “thought experiment” will completely clear up the subjekt: imagine the whole rotating waterbody to be suddenly frozen. if there were no wavebuilding humps on the poolbottom it would rotate further on in its circular bed. thus is prooven the absence of geometrical difficulties in the movement. also we learn that the outer spheres have to be faster than the inner ones. if we switch back to the liquid state we see, that ground friction is higher in the faster regions. here it becomes clear what has to be done about that: the driving force of the rotation, the pumpflow, has to be shot in the pool from the outer sidewalls. the angle of the pumpflow can be adjusted to produce exactly the decreace of speed towards the inner circle which prevents most turbulence.

due to normal vertical gravityvectors at the “standing waves” in the course, the waves should not be positioned radial to the center, but in a slightly angeled spiral to compensate downward drift.

now about the figures i came up with in my last post: 20yards diameter, 20 percent to horizontal.

the physics of rotation lead to simple equasions which i present in textform with following variables: g=gravitation ; w(speak omega)=the rotation ; R=radius ; a(speak alpha)=the angle ; tan=tangens ; p=pi ; P=period

w=squareroot((tan(a) x g)/ R)

w=(2 x p) / P

anyway - the results are the following: for a radius of 10 meters and an angle of 12 degrees( equals about 20 percent)

you need a circleperiod of 13.7 seconds resulting in about 4.5 m/s outer speed (around 16 km/h and whatever mph).

i´d say my first guess wasn´t so bad, because 16 km/h is a good wavecruising speed and probably the pumps can manage this too. maybe it´s a little harsh in crashevents.

last thing for today is to mention that the waterbody should be at least 80 cm deep because it rotates anyway and the groundfriction becomes a smaller part in relation.

i can only hope this got more transparent with only my words today

greetings to you and all - d.

16

Ok. I did understand the whole concept from the first post and had already thought about angeled waves in the pool. Would it be a complete bowl or rather a ring with a solid center? How many waves? I am not sure yhou could make it from one wave to the next on a 12% slope when you have still momentum against the flow left from getting of the first wave. Maybe when you get out over the upper shoulder of the fist wave and the next wave is already almost under that upper part. There will also be a lot of friction and very hard to compensate for currents from the waves if they start breacking. Where would you enter the ring and leave it? I know quite some rapids from kayaking and you simply don`t swimm in 4.5m/s fast streams. Have you ever surfed Wittelsbacher bridge in Munich? I did surf it several times with the kayak and think it is very unsafe to do so without a livewest. One guy once drowned after the wave. One thought in my construction was to narrow and flatten the bottom at the point where the wavestructure is located then increase the width again to slow down the water and allow for exit. The stream would still be fast enough for things like ropesurfing. I am alos very tired today or I would have done some drawings myself. greetings from Vienna.

17

hi marcus!

just a few quick repies to your thoughts, since i have loads of work to do till friday.

the strukture i think of is a ring. due to the hight difference between outer and inner waterline and the depth of the water itself the inner wall would have to be at least 2m, if the width of the course is 5m. here you see the chance of entrance into water speeds of only 2.25 m/s.

the physics of hydrodynamic roughly speaking suggest, that the is a big jump in energy consumption between green waves and waves with foam in them.

this you can see on rivers: green waves are followed by many resulting waves getting smaller and smaller, whereas white waves usually have only one hump behind them with slow water.

the idea is to let the waves break in the outmost sphere of the ring, where the pumps can compensate for the loss of energy, while the nonbreaking part will stay fast.

the angle of the wave has to be build such, that you can just ascend on it´s face from the inside with a carve and back down again with ease.

i really don´t picture the whole of the course as a scary washingmachine, but of course it´s basic idea is to be dynamic as hell.

greetings to you and all! - d.