[PSUBS-MAILIST] Hybrid ambient

Bill,

I put this info in my special file but I still find the engineering aspects of the hull design a bit scary. Get it wrong and implosion becomes an issue again.

Joe

From: "Dan H." <jmachine@adelphia.net>
Reply-To: personal_submersibles@psubs.org
To: <personal_submersibles@psubs.org>
Subject: Re: [PSUBS-MAILIST] Re: Variable Ballast Calculations, Bill
Date: Mon, 14 Nov 2005 08:04:17 -0500

Bill,

Don't forget that the air tanks you don't need to have in the sub are replaced with an air pump and a power source to operate it, or you have to use muscle power.

Also, hatches and viewports have to be built to withstand pressure from both sides. Not a big problem with smaller viewports, but a hatch has a big area and the latch has to hold it sealed. If you get to the surface before pumping down your internal air, you have 6000 pounds trying to blow a 24 inch hatch opened.

Dan H.

----- Original Message -----

From: Akins

To: personal_submersibles@psubs.org

Sent: Monday, November 14, 2005 2:26 AM

Subject: Re: [PSUBS-MAILIST] Re: Variable Ballast Calculations, Bill

Hi Paul.

I'd be glad to explain the values for you of compressing the subs interior atmosphere via the ballast tanks filling.

If your (AT THE MOMENT, because it becomes 1 atm again later) ambient tanks were filling without any air loss, that would compress

the interior atmosphere of your hull if your tanks were connected to the hull's interior.

The value of that would be that you did not lose any air and could pump the water back out of the

tanks using inside the hull pumps and then your atmosphere would expand again and be 14.7 psi and that means you could surface

without having to have air tanks. Which is exactly how the Hunley ballast tanks worked.

So one value would be you wouldn't need air tanks to surface with a savings on interior space. NO air tanks needed ever to blow.

Another value would be that, lets say you were at 2 atmospheres, or 33 feet, (remember we have 1 atm on us at the surface already)

and you allowed the incoming pressure of the ballast tanks filling to compress your internal atmosphere so the interior and exterior were

equalized at that depth, now lets say you closed off the water inlet valve at 33 ft, which would mean you wouldn't pressurize any more when you went deeper,

then that means you could decend another atmosphere (3 atm now) to 66 feet (by forcing the sub under with the planes) and only have ONE atmosphere of FELT external pressure

exerted against the outside of the sub even though you were at 3 atm. Because you already had the interior pressurized to 2 atm before

you shut off the valve. That means you could design a hybrid ambient/1atm sub with a hull that could go deeper than a typical ambient

could safely go because your body has to follow the "no decompression scuba dive table limits" and in a typical ambient at 66 ft your

body is under the pressure of 3 atm, whereas in the way I explained the hybrid above, your body would only be under the pressure of

2 atm even though your sub was at 3 atm. If you compressed your interior atmosphere ambiently to 33 ft so now your body would be under

2 atm, then you close off the valve, but you dive your sub to 99 ft or 4 atm and the outside water pressure on the sub is only 2 FELT atm because

the interior is pushing back with 2 atm of its own against outside water pressure. Not needing air tanks and your body able to be submerged

deeper and longer than in a normal ambient sub would be the main valuable benefits and a third side benefit would also be that your hull would

not have to be anywhere near as strong as a 1 atm hull because you are for a large part using it as an ambient hull which requires little strength and

thickness and you could submerge to deeper atmospheres with less FELT water pressure pressing against the hull because you already had

several atmospheres inside the sub pushing outward . Do these sound like valuable assets? I think they have possibilities for no decompression

ambient sub operation at scuba dive table limit depths.

Recap.....no air tanks needed for ballast tanks, body can dive deeper and longer than normal ambient sub

and hull doesn't need to be as strong as 1 atm WHEN USED AT PROPER DEPTHS FOR YOUR DESIGN.

Did that help you Paul?

Bill.

----- Original Message -----

From: Paul Kreemer

To: personal_submersibles@psubs.org

Sent: Sunday, November 13, 2005 11:42 PM

Subject: Re: [PSUBS-MAILIST] Re: Variable Ballast Calculations, Bill

Could someone please explain the value of connecting the ballast tank air volumes with the sub interior?

thanks-
Paul

On 11/13/05, Joseph Perkel <joeperkel@hotmail.com> wrote:

Bill,

"Now imagine.....you ENCLOSED those tanks so their bottoms were enclosed and then you put a water inlet on/off valve at the top of both tanks on the INSIDE of the sub. Now you'd have a Kittridge sub that had ambient tanks that as they filled they compressed the interior atmosphere of your sub"

This is an interesting idea worth investigating. I wonder though, about a disparity in volumes between the tanks and interior as well as rate of air flow and how everything ties together.

Thanks

Joe