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science guys! ... new idea - world's fastest bottles
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Okay, so I have this theory and idea to bike faster - basically a wave breaker for inside your bottles - it allows you to optimise your bottle to conserve momentum

theory - when you bike the fluid in your bottles sloshes back and forth. each time the fluids (about 700 grams per bottle) moves back and forth it has to gain momentum from somewhere which has to be, I assume, translated from pedalling power. Just like rocking your bike back and forth costs energy.

invention - a 3d hash tag shape insert for bottles - flexible so you can put it into your bottle , and its most of the vertical height of any bottle and expands to the perimeter shape. exact fit doesnt matter, because you just want to compartmentalise the fluid mass so that not all of it has to all the way back and all the way forward - basically a wave breaker inside your bottle
results - faster bike splits, or fresher legs after biking, better bike handling in corners, no momentum lag when you sprint or accelerate and wait for the fluid to rebound and catch up inside the bottles


so the top of it could look something like this....but the depth would be the height of a bottle that you can cut off to customise



is the theory right? how much savings could there from not pedalling water to the front of the bottle for 5 hours?
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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lacticturkey wrote:
Okay, so I have this theory and idea to bike faster - basically a wave breaker for inside your bottles - it allows you to optimise your bottle to conserve momentum

theory - when you bike the fluid in your bottles sloshes back and forth. each time the fluids (about 700 grams per bottle) moves back and forth it has to gain momentum from somewhere which has to be, I assume, translated from pedalling power. Just like rocking your bike back and forth costs energy.

invention - a 3d hash tag shape insert for bottles - flexible so you can put it into your bottle , and its most of the vertical height of any bottle and expands to the perimeter shape. exact fit doesnt matter, because you just want to compartmentalise the fluid mass so that not all of it has to all the way back and all the way forward - basically a wave breaker inside your bottle
results - faster bike splits, or fresher legs after biking, better bike handling in corners, no momentum lag when you sprint or accelerate and wait for the fluid to rebound and catch up inside the bottles


so the top of it could look something like this....but the depth would be the height of a bottle that you can cut off to customise



is the theory right? how much savings could there from not pedalling water to the front of the bottle for 5 hours?


Go for it!

Triathletes will buy it as long as you give them some calculations "PowerCrank-style".
Last edited by: windschatten: Dec 13, 17 11:24
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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Re: science guys! ... new idea - world's fastest bottles [JasoninHalifax] [ In reply to ]
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Similar things are used in motorsports to keep the fuel from sloshing around the tank and throwing the center of mass off and messing with your traction. So there's some precedent there, but mostly for cornering concerns, not front-back. If I remember correctly the ones I had seen used huge open-cell foam-ish material shoved into the tank to keep the liquids in place.

So yes, putting an insert would stop the fluid from moving around. But what advantage would that have? Good question.
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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Well... you might want to do some rigorous fluid dynamics modeling. It could be that enabling fluids to move freely is better than baffling the movement. Picture it this way... lets say you have a huge water bottle, and the water is free to move side-to-side. If you jerk the bike side to side, the fluid would stay in place relative to its original location (it would move relative to the bottle). In that scenario, no work is being done on the water, and jerking the bike back-and-forth takes less effort. However, if that water is bound to the bottle, and must move with the bike and bottle (it moves relative to original location, but not relative to the bottle), then you are doing work on the water, and using more energy.

I vote for no baffle.
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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I'm not sure this is a problem to begin with for mostly forward translation.. I understand the intuition that sloshing is bad, but that might not be the case. If you track the movement of the center of mass of the fluid in the bottle, it is moving forward and back in the bottle; to make it switch direction, the bottle is applying a force on it in oscillating directions. These should mostly cancel out (on first thought) so I don't think one would lose too much momentum/energy to this movement. Yes it takes energy to initiate this motion, but assuming there isn't much friction, it doesn't take much energy to keep that motion going. In fact, if you add friction to the system, it may actually result in the bottle being more parasitic than it would be otherwise.

In terms of stopping the sloshing motion, you're thinking about adding a damper to the system, which may indeed dampen out the oscillation if it is strong enough but that may not be necessary.

I like analyzing things - http://engineeringfitness.org
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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I don't think the sloshing is taking a measurable amount of energy from what you are putting into the bike, averaged over more than a second or so. After it sloshes backwards, it will slosh forwards.

As mentioned, there is some control of fuel movement in race cars but this is for maintaining balance for cornering. The amount of water in your bottle is not a concern for this.

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Ed O'Malley
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VeloVetta is developing AERO cycling shoes with CFD and wind tunnel testing.
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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Some of the handlebar drink systems have this in a form already. The mesh thing that the PD bottle had for instance.

Developing aero, fit and other fun stuff at Red is Faster
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Re: science guys! ... new idea - world's fastest bottles [stumpyx13] [ In reply to ]
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Hello stumpyx13 and All,

While it would slow you down a bit .... you could harness that slosh to power your Garmin.

https://www.cbsnews.com/...kes-us-debut-hawaii/

Solar collection on hat and shirt back would be more efficient and not slow you down and maybe keep you cooler.

http://www.dailymail.co.uk/...charge-phone-go.html

Cheers, Neal

+1 mph Faster
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Re: science guys! ... new idea - world's fastest bottles [SkippyKitten] [ In reply to ]
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SkippyKitten wrote:
Some of the handlebar drink systems have this in a form already. The mesh thing that the PD bottle had for instance.

That is/was to keep liquids from sloshing out of the bottle.

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Re: science guys! ... new idea - world's fastest bottles [nealhe] [ In reply to ]
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Yes! a little impeller in there connected to an alternator! You'd never need to change batteries in your power meter again!

-------------
Ed O'Malley
www.VeloVetta.com
VeloVetta is developing AERO cycling shoes with CFD and wind tunnel testing.
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Re: science guys! ... new idea - world's fastest bottles [RowToTri] [ In reply to ]
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RowToTri wrote:
Yes! a little impeller in there connected to an alternator! You'd never need to change batteries in your power meter again!

Use it to power the motor in your seat tube.
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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This is a big problem in liquid fuelled rockets actually and these baffles are installed inside the fuel tanks to prevent sloshing. So go for it. Make these. Market them as rocket-o-matic speed-o-whamo and triathletes will pay $50 a pop just for these baffles easy. We'll buy anything. It doesn't matter if it works or not.
Last edited by: Dilbert: Dec 13, 17 18:17
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Re: science guys! ... new idea - world's fastest bottles [RowToTri] [ In reply to ]
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RowToTri wrote:
I don't think the sloshing is taking a measurable amount of energy from what you are putting into the bike, averaged over more than a second or so. After it sloshes backwards, it will slosh forwards.

As mentioned, there is some control of fuel movement in race cars but this is for maintaining balance for cornering. The amount of water in your bottle is not a concern for this.

But think of the marginal gains! The way one could actually justify it (?) is that the forward slosh doesn't return quite all of the energy... some will be lost to turbulent (viscous) friction. What we need is a bottle or hydration system with hydrophobic inner surface so you're guaranteed to get all the water.

Vaguely relevant note: I did build a couple of cars using Fuel-Safe cells. The foam definitely works. But any significant methanol content turns it to crap.

Less is more.
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Re: science guys! ... new idea - world's fastest bottles [Big Endian] [ In reply to ]
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Formula 1 and rocket science endorsement sounds good!



While the forces and volumes for cycling are smaller we also don't have 1000hp engine so any energy saved is better.

Without science it's hard to estimate the energy savings. I can't imagine fluid pushing to the back of the bottle and staying there. Is it like a poster said that the water is relatively at constant speed and the bike is moving around it? I know energy isn't created or destroyed so when water moves back and forth that energy has to come from somewhere....guessing absorbing momentum from the biker. That force might be small or it might not....if you hold a filled bottle and just oscillate it slowly back and forth for an hour it definately feels like work and costs energy

The idea of the 3d hashtag over a sponge shape is so that bottle volume, drinking and filling speed aren't compromised

There might have to be some horizontal fins to prevent vertical sloshing inside the compartment

To test this theory could measure water bottle versus frozen water bottle on a model to see what the fluid inertia costs are?
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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lacticturkey wrote:
Without science it's hard to estimate the energy savings.

As you and others have mentioned, it shouldn't be too hard for someone with the requisite skills to model. I'd be surprised if it's a significant amount, even if you're crit racing with lots of cornering and accelerations.

Also, with respect to motorsport, one of the key reasons for fuel tank/oil sump baffles is to make sure that during periods of sustained sideways g-force (e.g. long corners) that all the fuel/oil doesn't slosh to one side of the tank, away from the feed pipe and starve the engine of fuel/oil. Obviously this isn't a concern in water bottles.
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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Can't wait for the double priced Carbon version of the basic plastic one! Saving me 0,001g!
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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You stop there with a baffle. Why not develop a KERS kinetic energy recovery system like formula 1 cars. Imagine the energy you could save with up top three sloshing water bottles on a bike that could be used later on hills or the overtake when pulling out the draft zone...

https://en.wikipedia.org/wiki/Kinetic_energy_recovery_system
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Re: science guys! ... new idea - world's fastest bottles [awenborn] [ In reply to ]
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awenborn wrote:
lacticturkey wrote:
Without science it's hard to estimate the energy savings.

As you and others have mentioned, it shouldn't be too hard for someone with the requisite skills to model. I'd be surprised if it's a significant amount, even if you're crit racing with lots of cornering and accelerations.

Also, with respect to motorsport, one of the key reasons for fuel tank/oil sump baffles is to make sure that during periods of sustained sideways g-force (e.g. long corners) that all the fuel/oil doesn't slosh to one side of the tank, away from the feed pipe and starve the engine of fuel/oil. Obviously this isn't a concern in water bottles.

I thought the OP was joking. Now, not so sure.

If there are energy losses from the water sloshing, then the baffle will increase the amount of energy dissipated (that's what baffles do) and make you slower. In theory anyway.

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Re: science guys! ... new idea - world's fastest bottles [JasoninHalifax] [ In reply to ]
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I thought the intention would be from preventing fluid accelerating and moving - thereby avoiding some dissipation?

An aero bottle already would reduce the distance fluid can slosh sideways, but increases the distance water can gain momentum in the other direction

If you have a BTA setup - and you brake - is there is a half kilo of water that shoots forwards - which could potentially affect handling - would baffles prevent acceleration or only spread out the dissapation across the chambers and end up with the same net forward force?
Last edited by: lacticturkey: Dec 14, 17 3:07
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Re: science guys! ... new idea - world's fastest bottles [lacticturkey] [ In reply to ]
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From a handling perspective possibly a difference in limiting sloshing.

From an energy perspective, it's all internal to "the system" and any energy imparted to slosh the water backwards pushed off the bottle in the forward direction in an equal but opposite manner negating the effect. The system in this case is you and your bike. From a handling perspective the mass movement is unpredictable, so the timing causes it to be an issue. From an energy perspective it will equalize over the oscillation of fluid movement. And the energy required to clean extra crap would negate any handling advantage.
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