Subsea heat exchanger

Abstract

A subsea heat exchanger comprising a bundle of tubes comprising at least one tube winding arranged to operate submerged in water and effective for guiding a fluid to be cooled by surrounding water in contact with the tube, the bundle of tubes defining a longitudinal extension and a perimeter. A plurality of nozzles are distributed in spatial relation to said perimeter, wherein the nozzles are effective for discharging jets of water impinging on the tubes, the nozzles oriented to induce, in the ambient water volume, a displacement that passes the perimeter at a plurality of locations and directions.

What is claimed is: 
     
         1 . A subsea heat exchanger comprising:
 a bundle of tubes, comprising at least one tube winding configured to operate submerged in water and to guide a fluid to be cooled by surrounding water in contact with the bundle of tubes, the bundle of tubes comprising a longitudinal extension and a perimeter; and   a plurality of nozzles distributed in spatial relation to the perimeter, wherein the nozzles are configured to discharge jets of water impinging on the bundle of tubes, and to induce in an ambient water volume a displacement that passes the perimeter at a plurality of locations and directions.   
     
     
         2 . The heat exchanger of  claim 1 , wherein the nozzles are further configured to generate a turbulent displacement of water near the bundle of tubes. 
     
     
         3 . The heat exchanger of  claim 1 , wherein the nozzles are arranged in a plane transversally to the longitudinal extension to discharge the jets of water at from about a tangential direction to about a 90° angle of impact with the perimeter of the bundle of tubes. 
     
     
         4 . The heat exchanger of  claim 1 , wherein the nozzles are arranged at an inclination in a plane parallel to the longitudinal extension to discharge the jets of water at from about a 30° to about a 90° angle of impact with the perimeter of the bundle of tubes. 
     
     
         5 . The heat exchanger of  claim 1 , wherein the nozzles are arranged radially outside the perimeter of a helical bundle of tubes, the nozzles mouthing inwards towards a center of the bundle of tubes. 
     
     
         6 . The heat exchanger of  claim 1 , wherein the nozzles are arranged radially inside a helical bundle of tubes, the nozzles mouthing outwards towards the perimeter of the bundle of tubes. 
     
     
         7 . The heat exchanger of  claim 1 , further comprising a manifold and a number of riser pipes extending from the manifold in the longitudinal direction of the bundle of tubes, each riser pipe supporting a set of the nozzles. 
     
     
         8 . The heat exchanger of  claim 1 , wherein the nozzles are controllable in common through a variable speed drive motor driving a sea water pump. 
     
     
         9 . The heat exchanger of  claim 1 , wherein the nozzles are controllable in common through a pressure regulating device in a water distribution manifold. 
     
     
         10 . The heat exchanger of  claim 9 , wherein the nozzles are distributed such that a first set of the nozzles is controllable separately from a second set of the nozzles. 
     
     
         11 . The heat exchanger of  claim 9 , wherein sets of the nozzles are alternatingly operable in consecutive order. 
     
     
         12 . The heat exchanger of  claim 1 , wherein the nozzles comprise ejectors operating in accordance with Bernoulli's principle. 
     
     
         13 . The heat exchanger of  claim 1 , wherein a flow pulse generator is installed upstream of the nozzles. 
     
     
         14 . The heat exchanger of  claim 1 , further comprising:
 a vertically oriented, non-ducted, spiral wound heat exchanger tubing open to surrounding seawater;   a circular manifold arranged in a lower end of the heat exchanger, the manifold supplied with seawater from a motor and pump assembly;   a number of riser pipes rising vertically from the circular manifold, angularly spaced about the spiral wound heat exchanger tubing; and   a set of the nozzles on each riser pipe, the nozzles mouthing radially inwards towards the center of the spiral wound heat exchanger tubing.   
     
     
         15 . The heat exchanger of  claim 1 , further comprising:
 a vertically oriented, non-ducted, spiral wound heat exchanger tubing open to surrounding seawater;   a circular manifold arranged in a lower end of the heat exchanger, the manifold supplied with seawater from a motor and pump assembly;   a number of riser pipes rising vertically from the circular manifold, angularly spaced inside the spiral wound heat exchanger tubing; and   a set of the nozzles on each riser pipe, the nozzles mouthing radially outwards towards the periphery of the spiral wound heat exchanger tubing.