Flat Bulkhead Tankage

This website...

http://www.astronautix.com/stages/satkhead.htm

...mentions a "flat bulkhead" for a possible Saturn IC revision that
"consists of multiple conical sections."

Does anyone have a handy (on-line) diagram of such an arrangement? I
think of cones as being round, like ice cream cones, and fail to see
how they'd be cobbled together into something that could be called
flat.

Mike Miller

..mentions a "flat bulkhead" for a possible Saturn IC revision that
"consists of multiple conical sections."

Does anyone have a handy (on-line) diagram of such an arrangement? I
think of cones as being round, like ice cream cones, and fail to see
how they'd be cobbled together into something that could be called
flat.


The closest thing that springs to mind is a paper from
NASA Langley, AIAA 99-0835, "Nontangent, Developed Contour Bulkheads
for a Wing-Body Single Stage Launch Vehicle", which indicated that
flattened ellipsoids (r:h = 3/7)would produce some 2.5% decrease in
tank weight. It should still be available from the NASA Technical
Reports Server.

A 'conic sections' isn't a cone, it's a shape you get when you take a
slice through a cone; circles, ellipses, hyperbolae, and things like
that are all conic sections, depending on the angle you take the slice
at. Probably this means a tank bulkhead that's an ellipse, or flattened
oval.

Mike Neame

Mike wrote:
A 'conic sections' isn't a cone, it's a shape you get when you take a
slice through a cone; circles, ellipses, hyperbolae, and things like
that are all conic sections, depending on the angle you take the slice
at. Probably this means a tank bulkhead that's an ellipse, or flattened
oval.

More exotically, might a matrix made from alternating pointing cones with
flattened hemispherical ends pack better than most others?
:q!

Mike wrote:
A 'conic sections' isn't a cone, it's a shape you get when you take a
slice through a cone

Ooooohhhhh. I see.

Mike Miller, Materials Engineer

So tanks shaped like M&Ms are better?

wrote:
This website...

http://www.astronautix.com/stages/satkhead.htm

..mentions a "flat bulkhead" for a possible Saturn IC revision that
"consists of multiple conical sections."

Does anyone have a handy (on-line) diagram of such an arrangement? I
think of cones as being round, like ice cream cones, and fail to see
how they'd be cobbled together into something that could be called
flat.


A conic section is a section taken from a solid cone shape and is
indeed flat.

Imagine the ice cream cone you were discussing, now imagine it is
solid, now imagine I have a sharp knife and cut a flat section of that
cone at an angle that is neither perpendicular nor parrallel to the
axis of the cone. the flat surface made by this cut is a conic
section.

Alfred Montestruc wrote:


wrote:
This website...

http://www.astronautix.com/stages/satkhead.htm

..mentions a "flat bulkhead" for a possible Saturn IC revision that
"consists of multiple conical sections."

Does anyone have a handy (on-line) diagram of such an arrangement? I
think of cones as being round, like ice cream cones, and fail to see
how they'd be cobbled together into something that could be called
flat.


A conic section is a section taken from a solid cone shape and is
indeed flat.

Imagine the ice cream cone you were discussing, now imagine it is
solid, now imagine I have a sharp knife and cut a flat section of that
cone at an angle that is neither perpendicular nor parrallel to the
axis of the cone. the flat surface made by this cut is a conic
section.

Definition:
A conic section is the intersection of a plane and a cone.

Sections parallel and perpendicular to the axis are still conic sections.

Starting with a perpendicular cut, eg a horizontal plane and a vertical
axis, we get a circle. Tilting the angle of the plane a bit, we get an
ellipse. Tilting some more, when the angle equals the angle of the cone we
get a parabola, and from there up to parallel with the axis we get a
hyperbola. When the plane is parallel to the axis, ie vertical in our
example, the section is known as a rectangular hyperbola.



The point, the line, and the pair of intersecting lines are also special
cases of conic sections produced when the plane intersects the vertex of the
cone.


--
Peter Fairbrother

Peter Fairbrother wrote:
Alfred Montestruc wrote:


wrote:
This website...

http://www.astronautix.com/stages/satkhead.htm

..mentions a "flat bulkhead" for a possible Saturn IC revision
that
"consists of multiple conical sections."

Does anyone have a handy (on-line) diagram of such an arrangement?
I
think of cones as being round, like ice cream cones, and fail to
see
how they'd be cobbled together into something that could be called
flat.


A conic section is a section taken from a solid cone shape and is
indeed flat.

Imagine the ice cream cone you were discussing, now imagine it is
solid, now imagine I have a sharp knife and cut a flat section of
that
cone at an angle that is neither perpendicular nor parrallel to the
axis of the cone. the flat surface made by this cut is a conic
section.

Definition:
A conic section is the intersection of a plane and a cone.

Sections parallel and perpendicular to the axis are still conic
sections.


Yes, but they have other names and need not have associated cones. All
circles are conic sections but not all circles need to have an
associated cone to define them. Likewise a two lines can define a
conic section that is a plane on which the axis of the cone exists, but
the two lines do not require the existance of the cone.