Flexible ocean upwelling pipe
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
- Resource Relation:
- Patent File Date: 1978 Aug 21
- Country of Publication:
- United States
- Language:
- English
Similar Records
Tension-leg off shore platform
Structure for offshore exploitation
Related Subjects
ocean
upwelling
pipe
thermal
energy
conversion
facility
cold
water
riser
releasably
supported
upper
hull
floating
substantially
vertical
below
floor
defined
essentially
entirely
material
modulus
elasticity
steel
density
polyethylene
compliant
resistant
applied
bending
moments
position
relative
stabilized
weight
suspended
line
apart
positively
buoyant
support
released
sinks
damaged
length
sufficient
allow
stop
contacts
thereafter
float
submerged
moored
communicates
sump
level
maintained
ambient
volume
heaving
preventing
collapse
substantially vertical
ocean thermal
water level
cold water
ocean floor
thermal energy
energy conversion
density polyethylene
bending moments
riser pipe
flexible line
floating facility
conversion facility
/114/60/138/414/441/