How do swimming pool wave machines work?

Posted by BackgroundCookie752@reddit | AskUK | View on Reddit | 28 comments

Could you please settle a discussion please? We are staying at Center Parcs at the moment (Elveden, best pool of them all!) and have been debating the wave machine. How does it work? I commented that it felt ‘more wavy’ swimming at night (7-8pm and predominately adults or larger kids) than it did in the daytime yesterday (2pm and heaving with children and families). I said I bet they turn the waves up when there’s less little ones. Other half said don’t be silly it’s not like a dial they can turn up or down it’s just the same. How do they make waves, and which of us is right?

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28 Comments

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One-Cardiologist-462@reddit

https://preview.redd.it/wp54zeqtfyfg1.png?width=1168&format=png&auto=webp&s=36160da4e9a29cad057e16073f64b5426641a5cf Excuse my poor paint skills, but this gives the general idea. An air pump constantly pulls air. Another valve periodically opens and closes. When the valve is open, air is admitted to the chamber, pulling the water level up. When the valve is opened, the vacuum is broken and the water level falls. The wave making chamber is separated by a grill to stop people being pulled inside, which would be very dangerous. I expect there are water level sensors in the chamber, to protect the motor from pulling in water, incase the level were to get too high. By only partially closing the valve, or operating the motor at a reduce power (or a combination of the two) you can reduce the amplitude of the waves created. By varying how often the valve is opened and closed, and the duty cycle of the open/close operation, the frequency and style of wave created can also be manipulated.

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National-Estate-7254@reddit

what about dump tank or drop tank systems that dont use pneumatic pumps? what type of mechanism releases the water from the tanks?

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NaaNaaRitRit@reddit

This explains everything perfectly, except for the need for a TIE Fighter.

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JeffSergeant@reddit

In case someone tries to fly into the outlet between cycles to blow up the motor.

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JurassicM4rc@reddit

Sounds tricky. Tell them to use the floats!

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DelosHR@reddit

You need a moon to make waves, obviously. But if you're stuck - a Death Star will do as a short term stand in.

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probablyaythrowaway@reddit

Poor stand in though, it’s no moon.

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NaaNaaRitRit@reddit

Oh, bravo.

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BackgroundCookie752@reddit (OP)

Thank you for the dedication to MS paint, this is much easier to picture!

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Jervis_Mantlepiece@reddit

>it’s not like a dial they can turn up or down It is exactly this.

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geeered@reddit

If you do surfing at the dedicated lake in Bristol they set different waves for different abilities.

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adamneigeroc@reddit

The wave garden makes waves using paddles in the central pier, the center parcs one is more head on, so different technology. Both can be turned up and down though

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CupofCursedTea@reddit

Another example - Typhoon Lagoon at WDW can create waves from “family friendly” to “surfing competition” level. So there’s obviously massive variation.

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SeniorPea8614@reddit

A vacuum pulls the water up, then drops it down. Apparently, there is a dial with five options. [According to this guy](https://www.google.com/search?q=wave+machine+how+it+works&rlz=1C5CHFA_enGB982GB982&ie=UTF-8#fpstate=ive&vld=cid:d3cc0439,vid:Ux7eBVt3kAM,st:0).

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Brilliant-Figure-149@reddit

I'm pretty sure some pedant/scientist (e.g. me) will be along shortly to point out that the vacuum doesn't "pull the water up".

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mellonians@reddit

Try a drink with a straw. It'll change your outlook on physics entirely.

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Brilliant-Figure-149@reddit

Nope sorry. The water goes up the straw for the same reason the swimming pool water goes up into the wave machine storage tank. (Hint - it's not "pulled up".)

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saywherefore@reddit

Simply set your zero pressure reference at atmosphere (commonly called gauge pressure) and the maths will absolutely show that the vacuum is pulling the water up. [Relevant xkcd](https://xkcd.com/123)

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s1kreddit@reddit

When I was in primary school one boy confidently told me they there is a tank full of sharks and when the pool attendants throw raw meat in when they want the waves.

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chris_567295@reddit

With a big long pipe to the ocean

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OkTadpole2920@reddit

I love Elveden, I'm going for a girls weekend in April.

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thomasthetanker@reddit

Really big bloke on the other side bobbing and down quickly.

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abfgern_@reddit

I'm just thinking out loud, but a pool full of people probably dampens the waves a fair bit compared with a comparatively empty pool. So you may well be correct in your observation, regardless of if a dial is used

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thetechguyv@reddit

You should have seen how hard the waves in that pool used to go before that kid died at one of the other sites. When I went this year the waves were basically a joke.

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BackgroundCookie752@reddit (OP)

Yeah we though they were tamer than expected, however the rest of the variety / slides / outdoor stuff makes up for it

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Mr-Incy@reddit

There are a few different ways, if there isn't a visible paddle or hydrofoil in the water, it is probably using 'dump tanks' that are either controlled by compressed air to push the water out, or are simply elevated, the water is pumped into the tank and when it reaches a certain level the water is released by the force of the compressed air or gravity. In the external tank system there will be a way to control at how much water is in the tank before it is released to create different wave sizes.

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beneyh@reddit

A giant piece of steel is pushed down at a specific force, pushing the wave towards you. So yes a dial exists

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