Chip,
I tried looking at that folder but get an
error, so unfortunately can’t see your drawings. I can send you some
literature (offline, due to the attachment size) on how to calculate this. But after
you’ve done all the math, I imagine you’ll
find an oval hull doesn’t make structural sense.
Rgds,
Alec
-----Original Message-----
From: Chuck Will
[mailto:chuck@bestan.com]
Sent: Tuesday, June 28, 2005 6:14
PM
To:
personal_submersibles@psubs.org
Subject: RE: [PSUBS-MAILIST] Hull
Shape question
I am still trying to
finalize the shape of the hull. I still would like to go with an oval hull. The
way I am looking at it is to use two fixed diameters to create the oval. It
will not be a random oval pattern. It will be created from a 48" diameter
tube and a 16" diameter tube. The top and bottom plate will be cut from
a 48" diameter tube cut at the point of intersection
with the 16" diameter side plates. It's sort of hard to explain so I
made a drawing. I don't know how to post to Moki so you can link to it at http://briefcase.yahoo.com/divetruk.
Look in the folder called drawings. The file name is "Oval Hull
Construction". The first page is 2D and the second page has a 3D
interpretation.
Basically I am
cutting two lengthwise sections of a large tube and welding the to two
sections of a smaller diameter tube. The would be extensive bracing on the
interior. I also wondered how I would do the hull calculations for strength.
Would I use the larger 48" diameter for all calculations? Or do I need to
do some math to figure a average diameter? Or am I still crazy to make my hull
oval? It just seems to fit what I want better.
-----Original Message-----
From:
owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org]On
Behalf Of Adam Lawrence
Sent: Tuesday, June 07, 2005 5:00
PM
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] Hull
Shape question
An oval shaped hull would be as
strong as the largest raduis. So if your hull is 4 feet wide and 2 feet tall it
would be about equivalent to calculating the strength of a round hull with a 7
foot radius. But then this isn't exactly true since you can reinforce the heck
out of it. But to maximize the weight to opperating depth ratio and usable
inside space, the solution converges on a round hull with simple ring stiffners.
----- Original Message -----
Sent: Tuesday,
June 07, 2005 3:48 PM
Subject:
[PSUBS-MAILIST] Hull Shape question
A quick question on hull
shape. I understand that the best shape for the pressure hull will be a sphere
or a round tube with braces and with domed end caps. How much strength is lost
with an oval tube? Imagine pushing down on a cardboard tube a bit.
Flatten it out lengthwise just a little. It would have bracing inside as well.
Any advice on this?