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Re: [PSUBS-MAILIST] Pressure air drive. (PSUB Turbo BOOST)
So, with one knot equalling 1.1508 statute mi. per hour/1.852 km per
hour, that makes it about 34.5 mi. per hour/55.5 km per hour. More
appropriate I think to call it 1,012 yards/926 meters per minute,
correct?
Carl
jbarlow@bjservices.ca wrote:
>
> Those are just the stats I found on the web for the fastest models mass
> produced. I have no idea how fast they actually went. I think that most
> actually used were electric (slower 30 kt) models.
>
> Jay.
>
>
> Coalbunny
> <coalbunny@vcn.com> To: personal_submersibles@psubs.org
> Sent by: cc:
> owner-personal_submersible Subject: Re: [PSUBS-MAILIST] Pressure air drive. (PSUB Turbo BOOST)
> s@psubs.org
>
>
> 08/01/2003 08:37 PM
> Please respond to
> personal_submersibles
>
>
>
> I had the understanding the rarely reached speeds over 40 mph.
> Carl
>
> jbarlow@bjservices.ca wrote:
> >
> > Actually I think they had a range of greater than a mile, but they
> > could rarely hit moving targets at ranges that equalled the Max range of
> > the torpedoes (As much as 14 km but more typically 3-5 km) I think they
> > must have been going slow by the time they reached the extreme ranges
> also.
> > They use a variety of engines (motors in some cases) including steam
> > turbines, engines, electric motors, and probably others. I think I read
> > somewhere that the torpedo motors developed hundreds of horsepower,
> (maybe
> > someone wants to calculate how much power it would take to push a 21"
> > Diameter torpedo at 45 kts (50 mph [80 km/h])!!! I'm happy to call it
> > lots!) I think that they didn't last very long though. That is they
> were
> > worn out after use. Might be an interesting TURBO BOOST for a PSub
> > though!! LOL.!!
> >
> > See this link for more info. These were German torpedoes. Japanese or
> > American ones were not much different, but I think the German ones
> > typically had better performance, and were copied in some cases by the
> > Allies.
> >
> > http://www.uboat.net/technical/torpedoes.htm
> >
> > http://www.regiamarina.net/arsenals/torpedoes/torpedo_us.htm
> >
> > Jay.
> >
> >
> > Coalbunny
> > <coalbunny@vcn.com> To:
> personal_submersibles@psubs.org
> > Sent by: cc:
> > owner-personal_submersible Subject: Re:
> [PSUBS-MAILIST] Pressure air drive.
> > s@psubs.org
> >
> >
> > 08/01/2003 04:52 PM
> > Please respond to
> > personal_submersibles
> >
> >
> >
> > And that would explain why WW2 torps had a range of less than a mile.
> > NOW I understand.
> > Thanks Jay!
> > Carl
> >
> > jbarlow@bjservices.ca wrote:
> > >
> > > 3 cubic feet per min at 90 psi
> > >
> > > If air is ideal gas then P1 x V1 = P2 x V2
> > >
> > > 3000 psi X .353 ft3 = 90 psi x V2
> > >
> > > V2 = 11.76 ft3 @ 90 psi
> > >
> > > 11.76 / 6 = 1.96 min.
> > >
> > > The volume gets worse by the head of water (15 psi per 32 feet) and
> also
> > > the motors lose power as then can't fully expand the air back to
> > > atmospheric to regain the stored energy. You could overcome this by
> > > feeding the motor ever increasing pressure air (measured inside your
> > boat)
> > > as you dove deeper. that is regulating it down less, to regain the
> power
> > > loss, but that again would shorten your range. 320 feet is about 150
> psi
> > > so now you need to feed the motors 90 + 150 = 140 psi to get .6 hp and
> > the
> > > 1.96 minutes becomes 1.26 minutes. Based on the 10 litre scuba bottle.
> > > Obviously one would need bottled gas cylinders.
> > >
> > > about 1.5 min per 10 litre bottle @ 10 atm. depth.
> > >
> > > Still a sound concept. If you have to use shop air (easy and cheap
> > > compressors) then i think it is not workable. If you have access to
> > > 3000-4000 psi compressors then it should work fine for short duration
> > use.
> > > For an occasional use would be great as it has no shelf life.
> > >
> > > Jay.
> > >
> > >
> > > MerlinSub@t-online.de
> > > (Carsten Standfuss) To:
> > personal_submersibles@psubs.org
> > > Sent by: cc:
> > > owner-personal_submersible Subject: Re:
> > [PSUBS-MAILIST] Pressure air drive.
> > > s@psubs.org
> > >
> > >
> > > 08/01/2003 10:47 AM
> > > Please respond to
> > > personal_submersibles
> > >
> > >
> > >
> > > Pierre Poulin schrieb:
> > > >
> > > > Hi,
> > > >
> > > > I've check some air grinders that could be transformed into motor.
> > > >
> > > > Free speed: 25000 rpm
> > > > - Operation pressure: 90 psi
> > > > - 0.6 HP
> > > > - Air consumption: 3 cfm
> > > > - Weight: 1.5 lb
> > > >
> > > > What do you think about that?
> > > >
> > > > Pierre
> > > >
> > >
> > > Hmm.. 3 cfm means cubif -foot- minute ?
> > > than it is
> > > are equal (sorry I think in metric..)
> > > to 3 x 0,3048 x 0,3048 x 0,3048 m = 3 x 0,028 m3 or 84 Liter
> > >
> > > if we estimate that the boat need two engines of 0,6 hp we need
> > > 2 x 84 liter = 168 Liter a minute.
> > >
> > > A normal scuba bottle has 10 Liters at 225 bars = 2250 Liters
> > > air and run the drive just 2250/168 = 13 Minutes
> > >
> > > A yard size bootle for weld gas has 50 liter and is 1,5 m (4,9 feet)
> > > high with a diameter of 280 mm (11 inch) runs about
> > > 5 times longer = 65 minutes..
> > >
> > > Two tanks of 50 Liters gives you 2 hours and 10 minutes..
> > > Not so bad - Batterys has to be replace after some years -
> > > pressure bottles not - and a 50 Liter industrial one is about
> > > 300 Dollar new and maybe cost the half if you purchase a used one.
> > >
> > > Problems:
> > > - to get an engine made from seawater resistant material
> > > - the noise ? -> no fish around the boat
> > > - the air bubbles all the time ? -> no fish around the boat
> > >
> > > Most problem is maybe that high pressure scuba compressor
> > > is mcuh more expensive than a battery charger.. :-(
> > > But for peoples which are allready scuba divers - and have allready
> > > a compressor - a solution.
> > >
> > > Carsten
> >
> > --
> > "You delight not in a city's seven or seventy wonders, but in an answer
> > it gives to a question of yours, or the question it asks you, forcing
> > you to answer, like Thebes through the mouth of the Sphinx." -- Kublai
> > Khan
>
> --
> "You delight not in a city's seven or seventy wonders, but in an answer
> it gives to a question of yours, or the question it asks you, forcing
> you to answer, like Thebes through the mouth of the Sphinx." -- Kublai
> Khan
--
"You delight not in a city's seven or seventy wonders, but in an answer
it gives to a question of yours, or the question it asks you, forcing
you to answer, like Thebes through the mouth of the Sphinx." -- Kublai
Khan