Dynamic vessel mooring system and method

Abstract

An example is directed to a mooring apparatus for mooring a vessel via a mooring buoy to an anchor under weather conditions from a light weather condition up to a preset maximum weather condition. A single-bouncer mooring apparatus includes a bouncer connected via an anchor line to the anchor having an anchor weight, the bouncer having a bouncer weight; and a catenary section line connected between the mooring buoy and the bouncer, the catenary section line having a catenary section length and a catenary section weight. The bouncer weight, the catenary section length, and the catenary section weight are selected to place the bouncer just touching the bottom of the body of water in the preset maximum weather condition for the vessel having the vessel length and the vessel weight. A multiple-bouncer mooring apparatus includes two or more bouncers connected in series via respective catenary section lines to the mooring buoy.

What is claimed is: 
     
         1 . A mooring apparatus for mooring a vessel having a vessel length and a vessel weight, via a mooring buoy to an anchor disposed at a bottom of a body of water under weather conditions from a light weather condition up to a preset maximum weather condition, the mooring apparatus comprising:
 two or more bouncers connected in series to the mooring buoy and including a distal bouncer which is connected via an anchor line to the anchor having an anchor weight, the two or more bouncers each having a bouncer weight; and   two or more catenary section lines including a first catenary section line connected between the mooring buoy and a proximal bouncer which is a first bouncer of the two or more bouncers;   the first bouncer being connected sequentially to an i-th bouncer as the distal bouncer in series via the two or more catenary section lines from the first catenary section line to an i-th catenary section line as a distal catenary section line; and   the two or more bouncers each having a bouncer weight and the two or more catenary section lines each having a catenary section length and a catenary section weight, which are selected to place the distal bouncer just touching the bottom of the body of water in the preset maximum weather condition for the vessel having the vessel length and the vessel weight.   
     
     
         2 . The mooring apparatus of  claim 1 ,
 wherein the preset maximum weather condition adds to a maximum of MLLW (Minimum Lower Low Water) by a tidal range and a storm surge to form a total water depth for placing the distal bouncer just touching the bottom of the body of water in the preset maximum weather condition.   
     
     
         3 . The mooring apparatus of  claim 2 ,
 wherein a total weight of the two or more bouncers has a limit of F Vmax , a comfortable vertical force, provided by a moored facility and the mooring buoy, and associated with an acceptable, relatively small longitudinal inclination or trim which would not affect the facility's function.   
     
     
         4 . The mooring apparatus of  claim 3 ,
 wherein the buoy end tangential force T, when the proximal bouncer is bouncing, is determined based on a unit weight in water of the proximal catenary section line q, the water depth h, and the bouncing bouncer's tangential force T bouncer , i.e., T=q*h+T bouncer , here T bouncer  being a combination of a weight in water of the bouncer W 1  and the horizontal force F H , T bouncer =sqrt (W 1   2 +F H   2 ).   
     
     
         5 . The mooring apparatus of  claim 1 ,
 wherein a number of the two or more bouncers, the bouncer weight of each bouncer of the two or more bouncers, and the catenary section length and the catenary section weight of each catenary section line of the two or more catenary section lines are determined using a catenary analysis, involving an iteration process running through each chain/hawser segment for each catenary section, to add up cumulatively the two or more catenary section lines sequentially from the first catenary section line to the distal catenary section line until the distal bouncer just touches the bottom of the body of water in the preset maximum weather condition.   
     
     
         6 . The mooring apparatus of  claim 4 ,
 wherein a distal catenary section length of the distal catenary section line may not be preset as that of a previous catenary section, but is tried out using an iteration process to add up cumulatively all of the segments on the tried length of the section to see if the distal bouncer just touches the bottom of the body of water in the preset maximum weather condition.   
     
     
         7 . The mooring apparatus of  claim 5 ,
 wherein a length of a proximal catenary section line is not preset but is determined using the catenary analysis involving an iteration process that runs through every segment until the proximal bouncer at the last segment just touches the bottom of the body of water in a light weather condition (e.g., the condition that generates the ¼ of the moored ship's maximum weather horizontal resistance, for the catenary section of a 3,000 lb proximal bouncer).   
     
     
         8 . The mooring apparatus of  claim 1 ,
 wherein the two or more bouncers each includes at least one of (i) a plate-like shape or (ii) a damper plate coupled thereto.   
     
     
         9 . The mooring apparatus of  claim 1 ,
 wherein the anchor comprises an array of ground anchors connected to the distal bouncer via their respective anchor lines, slack on seabed, with different length in different directions from the distal bouncer.   
     
     
         10 . A mooring apparatus for mooring a vessel having a vessel length and a vessel weight, via a mooring buoy to an anchor disposed at a bottom of a body of water under weather conditions from a light weather condition up to a preset maximum weather condition, the mooring apparatus comprising:
 a bouncer connected via an anchor line to the anchor having an anchor weight, the bouncer having a bouncer weight; and   a catenary section line connected between the mooring buoy and the bouncer, the catenary section line having a catenary section length and a catenary section weight;   the bouncer weight, the catenary section length, and the catenary section weight being selected to place the bouncer just touching the bottom of the body of water in the preset maximum weather condition for the vessel having the vessel length and the vessel weight.   
     
     
         11 . The mooring apparatus of  claim 10 ,
 wherein the preset maximum weather condition adds to a maximum of MLLW (Minimum Lower Low Water) by a tidal range and a storm surge to form a total water depth for placing the bouncer just touching the bottom of the body of water in the preset maximum weather condition.   
     
     
         12 . The mooring apparatus of  claim 11 ,
 wherein the weight of the bouncer has a limit of F Vmax , a comfortable vertical force, provided by a moored facility and the mooring buoy, and associated with an acceptable, relatively small longitudinal inclination or trim which would not affect the facility's function.   
     
     
         13 . The mooring apparatus of  claim 12 ,
 wherein the buoy end tangential force T is determined based on a unit weight in water of the catenary section line q, the water depth h, and the bouncing bouncer's tangential force T bouncer , i.e., T=q*h+T bouncer , here T bouncer  being a combination of a weight in water of the bouncer and the horizontal force.   
     
     
         14 . The mooring apparatus of  claim 10 ,
 wherein the bouncer weight and the catenary section length and the catenary section weight are determined using a catenary analysis, involving an iteration process running through each segment of the catenary section line until the bouncer just touches the bottom of the body of water in the preset maximum weather condition.   
     
     
         15 . The mooring apparatus of  claim 10 ,
 wherein the bouncer may be (i) a plate-like shape or (ii) a damper plate coupled thereto.   
     
     
         16 . The mooring apparatus of  claim 10 ,
 wherein the anchor comprises an array of ground anchors connected to the bouncer via their respective anchor lines, slack on seabed, with different length in different directions from the bouncer.   
     
     
         17 . A method of mooring a vessel having a vessel length and a vessel weight, via a mooring buoy to an anchor disposed at a bottom of a body of water under weather conditions from a light weather condition up to a preset maximum weather condition, the method comprising:
 connecting two or more bouncers in series to the mooring buoy, the two or more bouncers including a distal bouncer which is connected via an anchor line to the anchor having an anchor weight, the two or more bouncers each having a bouncer weight;   connecting a first catenary section line between the mooring buoy and a proximal bouncer which is a first bouncer of the two or more bouncers;   connecting the first bouncer sequentially to an i-th bouncer as the distal bouncer in series via two or more catenary section lines from the first catenary section line to an i-th catenary section line as a distal catenary section line; and   selecting the two or more bouncers each having a bouncer weight and the two or more catenary section lines each having a catenary section length and a catenary section weight, to place the distal bouncer just touching the bottom of the body of water in the preset maximum weather condition for the vessel having the vessel length and the vessel weight.   
     
     
         18 . The method of  claim 17 ,
 wherein the preset maximum weather condition adds to a maximum of MLLW (Minimum Lower Low Water) by a tidal range and a storm surge to form a total water depth for placing the distal bouncer just touching the bottom of the body of water in the preset maximum weather condition.   
     
     
         19 . The method of  claim 18 ,
 wherein a total weight of the two or more bouncers has a limit of F Vmax , a comfortable vertical force, provided by a moored facility and the mooring buoy, and associated with an acceptable, relatively small longitudinal inclination or trim which would not affect the facility's function.   
     
     
         20 . The method of  claim 19 , further comprising:
 determining the buoy end tangential force T, when the proximal bouncer is bouncing, based on a unit weight in water of the proximal catenary section line q, the water depth h, and the bouncing bouncer's tangential force T bouncer , i.e., T=q*h+T bouncer , here T bouncer  being a combination of a weight in water of the bouncer W 1  and the horizontal force F H , T bouncer =sqrt (W 1   2 +F H   2 ).   
     
     
         21 . The method of  claim 17 , further comprising:
 determining a number of the two or more bouncers, the bouncer weight of each bouncer of the two or more bouncers, and the catenary section length and the catenary section weight of each catenary section line of the two or more catenary section lines using a catenary analysis, involving an iteration process running through each chain/hawser segment for each catenary section, to add up cumulatively the two or more catenary section lines sequentially from the first catenary section line to the distal catenary section line until the distal bouncer just touches the bottom of the body of water in the preset maximum weather condition.   
     
     
         22 . The method of  claim 20 , further comprising:
 trying out a distal catenary section length of the distal catenary section line, which may not be preset as that of a previous catenary section, using an iteration process to add up cumulatively all of the segments on the tried length of the section to see if the distal bouncer just touches the bottom of the body of water in the preset maximum weather condition.   
     
     
         23 . The method of  claim 21 , further comprising:
 determining a length of a proximal catenary section line, which is not preset, using the catenary analysis involving an iteration process that runs through every segment until the proximal bouncer at the last segment just touches the bottom of the body of water in a light weather condition (e.g., the condition that generates the ¼ of the moored ship's maximum weather horizontal resistance, for the catenary section of a 3,000 lb proximal bouncer).   
     
     
         24 . The method of  claim 17 ,
 wherein the two or more bouncers each includes at least one of (i) a plate-like shape or (ii) a damper plate coupled thereto.   
     
     
         25 . The method of  claim 17 ,
 wherein the anchor comprises an array of ground anchors connected to the distal bouncer via their respective anchor lines, slack on seabed, with different length in different directions from the distal bouncer.