Water in Wing

[rolhardt]

A squeeze happens when there are more voids than air to adequately fill them at that depth (pressure). It's essentially a vacuum and given the opportunity, it will suck in water. The deeper you go the more water it will suck in until it equalizes to ambient pressures.

I agree. A wing that is nearly empty is essentially in a squeezed condition. Therefore, anytime you open a dump, whether air escapes or not, water will enter the wing. If the pressure inside the wing (or suit) was equal to the ambient pressure there would not be a squeeze--there would be equilibrium, which would allow water to enter also, albeit at a slower rate. If the wing is at a positive pressure no water will enter.

 

[The Chairman]

Pete had you stayed with Archimedes principle I would have said nothing more,

I doubt that!!!

but you felt the need to add that "gravity has nothing to do with it."

And I clarified that gravity was a constant for both water and the gas. But you simply want to fight: I get it.

Pete, which is it? "Bladder Suppleness" or Density / Buoyancy that causes wings to vent, under water?

I'm surprised that you have a hard time understanding this. Buoyancy causes the air to vent, and the suppleness allows water to replace some of that air. If it were like your steel bladder, it would be impossible for water to get in. It's nothing like that convoluted description though, and so the bladder remains partially inflated. You can say this is impossible, but whoop: there it is and I even provided photographic evidence.

 

[rolhardt]

Pete, I understand that buoyancy will allow the air to vent but I can't wrap my head around the "suppleness" issue. Would you mind explaining that one more time? TIA

 

[cool_hardware52]

I doubt that!!!

And I clarified that gravity was a constant for both water and the gas. But you simply want to fight: I get it.

Er ah well, that's a typical self serving revision of what you actually wrote, without gravity there would be no buoyant forces. Tell me how does Archimedes principle work in zero G?

BTW, gravity has nothing to do with it either. The gravity exerted on the air and the water are constant. The only issue is density as demonstrated by Archimedes Principle.

I'm surprised that you have a hard time understanding this. Buoyancy causes the air to vent, and the suppleness allows water to replace some of that air. If it were like your steel bladder, it would be impossible for water to get in. It's nothing like that convoluted description though, and so the bladder remains partially inflated. You can say this is impossible, but whoop: there it is and I even provided photographic evidence.

I'm surprised you think gravity plays no part in buoyancy.

What exactly do you think you have proven about wings and water intrusion by deflating one on your couch? The entire "experiment" is kinda sad IMO.

Even with a SS Bladder there would be water intrusion for exactly the reasons I and several others have noted. The gas that's venting is doing so with very little force and velocity. That allows water to enter at the same time the gas is leaving. The volume of the corrugated hose and power inflator and elbow with are all fairly rigid and allow water to enter. This only stops when there is no more air to vent, regardless of what material they are made of.

If you think welding two 4' diameter pieces of 16 gauge together creates some sort of super spring loaded "memory metal" vessel that's going to snap back together instantly your just wrong. Sorry I thought you had some practical experience with metal working.


Tobin

 

[The Chairman]

Pete, I understand that buoyancy will allow the air to vent but I can't wrap my head around the "suppleness" issue. Would you mind explaining that one more time? TIA

Sure. Water is far more dense than air. Consequently, it's easier for the air to leave than for the water to enter. In it's rush to leave, a very slight vacuum is created in the cell by the departing air but that's negligible. Any elasticity of the cell would enhance this effect but most bladders have little and they tend to remain in the shape they were in. This allows water to enter. As I've pointed out again and again: it's perfectly normal.

 

[rolhardt]

Thanks. I know it's normal and until today I had never given it a second thought. I keep going back over that (crazy?) wing and drysuit comparison. Where does that theory go off the rails?

 

[The Chairman]

It's simple physics and a matter of perspective. It's about relative vacuums and not absolute ones. Perhaps if you could understand that Centigrade and Fahrenheit are relative measurements whereas Kelvin and Rankine are absolutes (mostly), you can get your mind around it all.

 

[Jack Hammer]

Reading this thread I picture you guys reaching deep into your pocket protectors and pulling your slide rules out and using them for a 1722 style duel to the death.... And yes, you're both wearing frilly shirts...



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[cool_hardware52]

I planning an "experiment" where I leave an open cardboard box on my couch overnight. Maybe I'll video it. Not sure what it has to do with wings used underwater but apparently pictures of nonsense are assumed to add creditibility……...

Tobin