Hey guys, I’m curious if anyone knows whether or not a pressurized vessel floats better than a non pressurized vessel. For example, say a 5 gal tank is empty and it is X amount boyant. Will it’s boyancy increase or decrease as PSI is increased? or does that not effect it? I’m just brain storming.
Depends on the weight (density) of what is in the 5 gallon tank. The heavier (more dense) the substance the less likely it is to float. Althought the tank itself (empty) will float, if the substance inside the tank is more dense than the tank and the water it is floating in, it will sink.
Make sense?
Yeah, that makes sense. But it will be filled with air. I should of specificed I guess but I assumed that was obvious. Air will float out of water (bubbles) but I am just not sure whether more air condensed in the same space will result in more boyancy or not. Kinda wish I watched the discovery channel special on submarines.
I would imagine that no matter how dense the air is (compressed) the buoyancy will change minimally. Air is much different than say propane or gasoline, etc. (now I’m just guessing though)
A submerged object’s buoyancy (the upward force exerted on it by a fluid) is exactly equal to the weight of the fluid it displaces. In this case, the upward buoyant force on the gas tank? is equal in amount to the weight of the water it displaces. Since the tank is essentially incompressible, it always displaces the same volume of water. And since water is essentially incompressible, that fixed volume of water always weighs the same amount.
i bet jeff95ta or jethro will know
So I would need to increase the displacement of the water instead of increasing the PSI?
A non-pressurized vessel will float higher than the pressurized vessel, although marginally. There are less air molecules to weigh the container down.
What exactly are you trying to accomplish?
I had planned on building my own trailor for my gas powered scooter to tow with my truck. Well want to tow a jet ski instead, and want an easy way to load/unload it from the trailor. I wanted it to float as i back it into the water, disconnect the machine, then sink the trailor a little bit and pull out. Something to that effect.
how about you just back it in normally.Besides if you are backing into the river or what not you do not want a floating trailer on your trailer hitch with the current. that could cause problems.
I don’t like to do anything ‘normally’. That’s the pussy way. haha j/p
But I think I’ll need the extra floatation so my truck can actually pull it out of the water. Plus the air system is already there, so I figured why not?!
But it seems throughout the forums I’ve posted this on the consensus is I need more volume in the vessel, not more PSI. Back to brain storming.
you are over thinking this. flotation isn’t going to help anything. If your truck needs help pulling out a jet ski size trailor, you need a better truck (no offence). if you make that trailor float I;m telling you especially in a river setting you are going to have a hell of a time and have damage caused.
ppppbbbbbbffffffff, I’ll make it work. Somehow.
if you can’t pull it out with low gear you’ shouldn’t be using it for that purpose. Do you have 4x4?
cool and maybe I will see your bumper floating down the river this summer when I’m out on my dads boat…
Do you want us to pull it back in for you 
Nope.
well, there is no ‘bumper’ per say on my truck, but if you see any peice of it floating by, I’d appreciate it’s recovery.
even with a lowered truck and no 4 wheel drive you shouldn’t have an issue pulling a jet ski trailer. Actaully since ur truck is lowered i think if the trailer was made boyant that while conected to ur hitch it would pull up and actaully give you less traction, sorta like if two people were pulling up on either side.
Now why would I know something like this…
A vessel pressurized with air will actually be less buoyent than the same vessel filled with air at atmospheric pressure. The reason for this is as you increase the pressure, you are forcing more more mass in. An increase in mass results in an increase in density. Buoyency is a result of the differential between densities. So in theory, pulling a vacuum on a vessel will result the greatest buoyency.
I guess no one thought of how submarines work…
lazyness > silly research