Oblate Ellipsoid Dome Calcs Reference
- Diameter of the base of the dome. The semi-major axis (a) of the ellipsoid
will be defined as half of the diameter. (see diagram above)
- Height of dome from base to apex. The semi-minor axis (b) of the ellipsoid
will be defined as equal to the height. (see diagram above)
- Vertical wall equal in diameter to the base of the dome extending
from the base down to the ground. For half-ellipsoids -- where the height
is equal to half the diameter -- the stemwall can usually be inflated
as part of the Airform. These formulas are setup to only calculate half-ellipsoids.
Orion style walls may be built if you choose, however, low profile spherical
domes may be more appropriate. (see diagram above)
- The ratio between the a and b of the ellisoid shape where 1.0 is a
sphere, 1.35 is a moderately elliptical dome, and 1.45 is a highly elliptical
- Distance around the perimeter of the dome.
- Floor Area
- Area of the floor. The floor is defined as a circle equal to the diameter
of the base of the dome.
- Surface Area
- Dome, Stemwall, and Total Surface Area describe the surface area of
the dome and stemwall separately and then totals the two together.
- Dome, Stemwall, and Total Volume describe the cubic volume contained
by the dome and stemwall separately and then totals the two together.
- The level above the base of the dome to calculate radius and area.
(see diagram above)
- Radius @ Level
- The horizontal radius at the 'Level' specified. (see diagram above)
- Area @ Level
- Area of the circle described by the Radius @ Level.
A Prolate ellipsoid is a solid of revolution arrived at by revolving the ellipse around the long axis of the ellipse. The height of the half ellipse is the same as the b distance as it derived by revolution.
The ellipsoid will have more surface area to floor area than a spheroid.