by Mawgan on November 2nd, 2007

Question

Help answer this question below.

Why can a bathyscaphe dive much deeper a conventional submarine?

Like
Report

Share:: Facebook; Twitter; Other

Answers. 2 helpful answers below.

by scubabob on November 2nd, 2007
The pressure hull ( where the operators are) in a bathyscaphe is a sphere, where the force of the ambient water pressure is exerted equally from all directions at the same time inwards. A traditional submarine's pressure hull is a modified cylinder and is structurally inferior to resist the inwards water pressure that a true sphere can withstand. That's for starters.
A bathyscaphe also employs a different method of buoyancy control that relies on a liquid that is less dense than water. Liquids, are more or less, incompressible and a tank filled with a liquid, won't implode at depth. A traditional submarine employs air in ballast tanks, to provide buoyancy. Air IS compressible. Even if your pressure hull remained intact and you emptied your ballast tanks of air and replaced it with water, you might avoid being crushed, but if you did it at great depth, you'd have an issue getting back to the surface, unless your air source to fill those tanks to get positive again, is powerful enough to overcome the current ambient pressure. A bathyscaphe need only ditch onboard lead shot to become buoyant.
Comments
Add a comment...
- Like
- Report
No comments. Post one | Permalink
by The Chief on October 18th, 2009
There are several reasons, and Scubabob covered some very important ones.

They ultimately relate back to what each are designed for. A submarine is NOT designed to be a simple, deep diving ship. She is designed to be a mobile, submersible weapons platform, built to be highly maneuverable, carry many people, surface, dive, and maneuver on her own power, and operate in virtually all aquatic environments under all adverse conditions.

By contrast, a bathyscaphe is designed primarily with the purpose of making slow, controlled descents and ascents to and from great depths carrying a minimum number of people (usually only one or two), under carefully controlled conditions in the best of weather, and while being serviced by a support ship. And she's pretty much limited to taking pictures/video and maybe operating a remote handling device of some kind.

To that end, it's much easier to design a spherical pressure chamber which can withstand far greater sea pressures for the purposes that are suitable for a bathyscaphe than it is for a submarine. Spherical shapes can naturally withstand far greater pressures before catastrophic failure.

Cylindrical chambers required for submarines cannot withstand such pressures.

That about sums it up.

:):)
Comments
- plus6
  
  Report
  
  by Seeya says Dont Ever Give Up on October 20th, 2009
- :):)
  
  Report
  
  by The Chief on October 20th, 2009
Add a comment...
- Like
- Report
2 comments | Post one | Permalink