There is a backup tank shown in the picture.DemoCoder said:
Diving without oxygen bottles
- Thread starter Druga Runda
- Start date
Just drop a little ballast weight and you'll float up to the surface with no exertion whatsoever neccessary...DemoCoder said:
I would still think tho that a filter large enough to feed a human being with oxygen would create horrendous drag. The oxygen wouldn't be extracted as gas on the other side either, so a completely unpowered solution looks rather unfeasible to me, but it's a neat idea for sure.
Killer-Kris
Regular
Guden Oden said:Just drop a little ballast weight and you'll float up to the surface with no exertion whatsoever neccessary...DemoCoder said:
That is until your lungs and sinuses explode!
Always breath out when going up.
Killer-Kris
Regular
That's also provided you ascend at a controlled rate. Too fast and you still won't be able to breath out fast enough. Or worse, get the bends.
If 1.5 mass-% of water is dissolved air, then there's LOTS of oxygen in water. (15 times more in 1 m^3 of water than in 1 m^3 of air at atmospheric pressure. And no I'm not counting the H2O.)
One typical breath of 500 ml would need the air in 33 ml of water. But it most likely need some more water since you can't expect to extract 100% of it.
A re-breather with this "gil" instead of the O2 tank could work well. But for a fast decent, you'd probably need more diluent gas than you can extract from the water (without risking O2 poisoning).
One typical breath of 500 ml would need the air in 33 ml of water. But it most likely need some more water since you can't expect to extract 100% of it.
A re-breather with this "gil" instead of the O2 tank could work well. But for a fast decent, you'd probably need more diluent gas than you can extract from the water (without risking O2 poisoning).
Basic said:
If it functions as expected, the only thing that is extracted from your original mixture is CO2. But you do need different kinds of "filler" molecules, depending on the depth you're operating at. Like nitrogen at the surface, and helium at more than 66 meters. And it isn't 100% effective. But it gives you a very much extended duration for the depth you're at.
digitalwanderer said:
Yep rebreathers actually predate scuba tanks.
They are considerably lighter and can supply for extended periods.
The problem with rebreathers is their failure modes, when a scuba tank fails it basically stops giving you air, so you swap to you're backup, or your buddies backup.
When a rebreather fails you keep breathing CO2 so you pass out and die with no indication that anything is wrong.
Of course there are various electronic monitoring devices on modern rebreathers, but they are considered unreliable by many in the diving community.
Personally I'm interested in anything that saves me having to lug 90lbs of equipment accross a beach while wearing what amounts snow skiing levels of insulation covered in a plasic bag. just so I can spend 60 minutes or so floating around in water with 20ft visibility on a good day. Sad thing is I regularly drive 2Hrs on a weekend to do just that :/
Killer-Kris said:
Nope in fact as long as your glotis is open it'll all expell itself. Short of physically holding your breath your not going to get an air embalism.
Now if you were down for long enough you have a potential problem with decompression sickness.
The general rule is if you have a problem underwater you do everything you can to solve it without surfacing.
DiGuru said:
I know our attack divers(direct translation, dunno an english term, kinda like SEALs anyway), of the coastal rangers use them. The main reason of course is that they don't leave a bubble trail on the surface. That and they get a lot longer time under water.
Oh yeah, and they breathe pure OX under water also! Pretty dangerous, but I guess it enhances endurance, and I don't think they dive deeper than 8m while doing so.
MPI said:
Not that expensive (in the scheme of scuba gear) unless you want to dive deep. No more perishable parts than standard scuba gear.
Questionable safety in a recreational setting, although they're pretty popular with underwater photographers.
Basically at the simplest level there are 2 different sorts of rebreathers, closed circuit, where all of the gas is recirculated and no gas is vented except on ascent. and semiclosed circuit rebreathers where some percentage of the gas in the loop is vented on every breath. The former are actually simpler, but there is a lot more scope for both user error and failure (They either rely in manual addition of diluent or O2 or they rely on computer cntrolled valves). The Semi closed circuit rebreaters either use a trickle system where you basically have a slow leak into the loop, or they are demand based and maintain the PPO2 because a certain percentage of the gas isvented on every breath.
DiGuru:
Let me give some more detail on what I meant.
The article says that there's 1.5% of air in the water, which means that there are plenty of N2 in it too. So the "gil" will give you a N2/O2 mix. (Similar mix as atmospheric air?)
As you use the O2 in the mix and remove CO2 with the scrubber, you will get filler N2 on the side. For a slow decent, that could be enough. But for faster decents than that, you need a diluant tube.
And yes of course, only as long as you keep within depths where you don't need other diluents than N2. I guess this system is pretty useless for breathing when you get to depths where you can't use N2. Unless you find a N2-scrubber.
Let me give some more detail on what I meant.
The article says that there's 1.5% of air in the water, which means that there are plenty of N2 in it too. So the "gil" will give you a N2/O2 mix. (Similar mix as atmospheric air?)
As you use the O2 in the mix and remove CO2 with the scrubber, you will get filler N2 on the side. For a slow decent, that could be enough. But for faster decents than that, you need a diluant tube.
And yes of course, only as long as you keep within depths where you don't need other diluents than N2. I guess this system is pretty useless for breathing when you get to depths where you can't use N2. Unless you find a N2-scrubber.
Karma Police
Regular
Basic said:
I was about to ask about the N2. When I got my diving liscense the one thing that I didn't know is the importance of breathing N2 when diving.
I'm sure it will have problems, but the idea of diving without a tank that weighs 5 times as much when out of the water is very appealing to me.
This invention isn't about a membrane though. The brief description mentions a centrifuge to make a pressure difference that is enough for the air to be released from the water.
If there is a membrane that can separate O2 from N2 then it all gets a lot better. I just get the feeling that it might be hard to find such a membrane though. With O2 and N2 being too similar.
If there is a membrane that can separate O2 from N2 then it all gets a lot better. I just get the feeling that it might be hard to find such a membrane though. With O2 and N2 being too similar.