Flexible ocean upwelling pipe

Patent · 01 January 1980

OSTI ID:863702

Person, Abraham

In an ocean thermal energy conversion facility, a cold water riser pipe is releasably supported at its upper end by the hull of the floating facility. The pipe is substantially vertical and has its lower end far below the hull above the ocean floor. The pipe is defined essentially entirely of a material which has a modulus of elasticity substantially less than that of steel, e.g., high density polyethylene, so that the pipe is flexible and compliant to rather than resistant to applied bending moments. The position of the lower end of the pipe relative to the hull is stabilized by a weight suspended below the lower end of the pipe on a flexible line. The pipe, apart from the weight, is positively buoyant. If support of the upper end of the pipe is released, the pipe sinks to the ocean floor, but is not damaged as the length of the line between the pipe and the weight is sufficient to allow the buoyant pipe to come to a stop within the line length after the weight contacts the ocean floor, and thereafter to float submerged above the ocean floor while moored to the ocean floor by the weight. The upper end of the pipe, while supported by the hull, communicates to a sump in the hull in which the water level is maintained below the ambient water level. The sump volume is sufficient to keep the pipe full during heaving of the hull, thereby preventing collapse of the pipe.

• Research Organization: Global Marine, Inc., Los Angeles, CA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC03-78ET20539
• Assignee: Global Marine, Inc. (Los Angeles, CA)
• Patent Number(s): 4,231,312
• Application Number: 05/935673
• OSTI ID: 863702
• Country of Publication: United States
• Language: English

Related Subjects

/114/60/138/414/441/
allow
ambient
apart
applied
below
bending
bending moments
buoyant
cold
cold water
collapse
communicates
compliant
contacts
conversion
conversion facility
damaged
defined
density
density polyethylene
elasticity
energy
energy conversion
entirely
essentially
facility
flexible
flexible line
float
floating
floating facility
floor
heaving
hull
length
level
line
maintained
material
modulus
moments
moored
ocean
ocean floor
ocean thermal
pipe
polyethylene
position
positively
preventing
relative
releasably
released
resistant
riser
riser pipe
sinks
stabilized
steel
stop
submerged
substantially
substantially vertical
sufficient
sump
support
supported
suspended
thereafter
thermal
thermal energy
upper
upwelling
vertical
volume
water
water level
weight