[PSUBS-MAILIST] Diesel Exhaust

Sat Oct 12 07:46:26 EDT 2013

Now THAT is a thoroughly thought-out solution. One for the archive...

Thanks for taking the time to explain this.

Best,
Marc

On 10/12/2013 4:28 AM, Hugh Fulton wrote:
> Hi Marc,
>
> I am in the final throes of finishing twin engine driven 2 man and I
> have opted for the following:
>
> 2 x 2” Snorkels with plastic float valves leading into the cabin through
> 2 x 2” combination valves being manual ball valves coupled to air
> actuated shuttle valves and fitted with non return valves.
>
> This means that the non return valves will vent overpressure situation
> on the surface and blow out through the snorkel float valves.
>
> The snorkels are located inside an airbox leading into the boat part
> which has about 4 cubic meters of air volume so that if I go through a
> wave the float valve does not get to close and the air is drawn from the
> “air box” volume for a brief period.
>
> The air is then drawn from the cabin again through 2 x combination
> valves into the engine pressure chambers.  The exhaust which also takes
> a large portion of the engine cooling water goes through a raised
> exhaust line above the water level then down through an air operated
> shuttle valve and a non return valve exiting underwater through the
> center of the propeller as per an outboard motor or stern leg.
> According to the rules you should have 2 valves on the exhaust.  I am
> relying on the air drawn through the cabin for cooling and as most of
> the cabin is protected by fiberglass I am hoping that it wont get too
> much direct heating from the sun apart from through the domes.  When the
> air operated shuttle valves are closed ready for diving the engines will
> pull a vacuum of approx 1-2 psi before shutting down.  IF no vacuum
> maintained then no dive and the engines keep running.  All untested yet
> but hoping I am only about 8 weeks away.  Carsten’s system is all tested
> and proven.  Regards, Hugh
>
> *From:*Personal_Submersibles
> [mailto:personal_submersibles-bounces at psubs.org] *On Behalf Of *
> *Sent:* Saturday, 12 October 2013 6:33 a.m.
> *To:* Personal Submersibles General Discussion
> *Subject:* Re: [PSUBS-MAILIST] Diesel Exhaust
>
> Hi Marc,
>
> before I response in detail, which size should the sub have? And which
> range?
>
> And which kind of wave high, wave length and weather you want to survife
> on the surface?
> Any concept sketch? Do you like to snorckel with the sub?
>
> Euronaut has more problems with the short medium high wave in the baltic
> than with the high but long waves in the north sea.
>
> Bad weather in the north sea lift the hole boat before the wave reach
> the sail, but in the Baltic the waves are
> shorter and did mot lift the boat so much - as result the sail goes very
> wet. Like in the movie "Das Boot"
>
> Short wave in the baltic:
> http://www.euronaut.org/content/gfx/operational/IMG_8705.jpg
>
> Here the over waterline exhaust of Euronaut in operation.
> The funny sound comes from a wave flap close to the end of the exhaust
> which goes up and down at idlle speed.
> http://www.youtube.com/watch?v=PT7i05s92ak
>
> Cooling is also something you should have in mind.
>
> And noise..
>
> And..
>
> vbr Carsten
>
> *From:*Marc de Piolenc <piolenc at archivale.com
> <mailto:piolenc at archivale.com>>
> *To:* personal_submersibles at psubs.org
> <mailto:personal_submersibles at psubs.org>
> *Sent:* Thursday, October 10, 2013 10:15 PM
> *Subject:* Re: [PSUBS-MAILIST] Dive report - Pickles Reef
>
>
> I've been following this discussion with great interest. I
> don't have a
> sub yet, but I do live in the Tropics, and as there's no cold current
> handy to where I live any subbing I do will be in water pretty near air
> temperature. As you might expect, I've given this problem a lot of
> thought.
>
> My tentative conclusion is that, if I build a sub, I will have to make
> it more autonomous than is the rule on this list. Specifically, it will
> need a combustion engine to ferry itself on the surface to dive sites,
> and to maintain comfort and keep the battery topped off for diving while
> doing so. I started with the assumption that I would need an air
> conditioning unit running off a small industrial diesel, but then I
> realized that, if I use a snorkel exhausting into the cabin, and have
> the diesel draw air from the cabin, I get continuous renewal of the air
> in the cabin without the cost, power burden and safety problems of
> running a Rankine cycle refrigeration system. That's the solution that
> I've retained for the moment. Of course I also need a secure means of
> preventing exhaust gas from being aspirated into the snorkel (I can't
> quite understand how naval submarines manage to combine both functions
> in one mast), but that might be as simple as having the diesel exhaust
> flush with the hull, with some arrangement to prevent water from coming
> in. Since the diesel would only be used on the surface, and the snort
> would only be there to allow a low-freeboard hatch to be kept closed,
> the power penalty would be minimal.
>
> Fuel storage, fuel feed and the like still have to be worked out. Naval
> submarines have very complex arrangements for this, and that complexity
> must be tolerated for a good reason. Even so, I need a simpler way to do
> it that still protects the fuel from contamination and me from asphyxiation.
>
> Marc de Piolenc
>
> --
>
> Carsten Standfuß
> Dipl.Ing.Schiffbau @ Meerestechnik
> Heinrich Reck Str.12A
> 18211 Admannshagen
>
> 0172 8464 420
> WWW.Euronaut.org <http://WWW.Euronaut.org>
> Carsten at euronaut.org <mailto:Carsten at euronaut.org>
>
> __________ Information from ESET NOD32 Antivirus, version of virus
> signature database 8903 (20131010) __________
>
> The message was checked by ESET NOD32 Antivirus.
>
> http://www.eset.com
>
>
>
> __________ Information from ESET NOD32 Antivirus, version of virus
> signature database 8903 (20131010) __________
>
> The message was checked by ESET NOD32 Antivirus.
>
> http://www.eset.com
>
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>

-- 
Archivale catalog: http://www.archivale.com/catalog
Polymath weblog: http://www.archivale.com/weblog
Translations (ProZ profile): http://www.proz.com/profile/639380
Translations (BeWords profile): http://www.bewords.com/Marc-dePiolenc
Ducted fans: http://massflow.archivale.com/