Vortex generator system and method for ship form drag reduction

Abstract

A vortex generation system and method for reducing hydrodynamic drag in ships with high block coefficients is disclosed. The system includes a hull and a plurality of vortex generators affixed circumferentially to the hull at locations determined relative to the point of detachment of the boundary layer. Each vortex generator features substantially triangular surfaces with dimensions, such as height, width, and surface area, optimized using a data-driven methodology employing Gaussian Process Regression (GPR). The method iteratively analyzes computational fluid dynamics (CFD) models to identify optimal design parameters, including wedge angle, longitudinal position, and density of vortex generators, which minimize form drag while maintaining low skin friction coefficients. This system significantly enhances fuel efficiency and operational performance by addressing the moving detachment point dilemma and optimizing vortex generator configurations. Applications include marine vehicles and submerged structures, with scalability ensured through calculated scaling factors for full-scale implementation.

What is claimed is: 
     
         1 . A wedge-shaped vortex generator for reducing hydrodynamic drag in a marine fluid environment, comprising:
 a monolithic body having:
 an upper face configured with a convex curvature, a base face, a rear face, and a pair of laterally opposed side faces; 
 wherein the body is defined by at least one of: a wedge angle, a wedge elevation angle, a tip-to-base length, and a base bottom width; and 
 wherein the convex upper face is shaped to promote the generation of streamwise vortices by re-energizing an adjacent fluid boundary layer to delay flow separation. 
   
     
     
         2 . The wedge-shaped vortex generator of  claim 1 , wherein the wedge angle is between 25 degrees and 35 degrees. 
     
     
         3 . The wedge-shaped vortex generator of  claim 1 , wherein the wedge elevation angle is between 15 degrees and 20 degrees. 
     
     
         4 . The wedge-shaped vortex generator of  claim 1 , wherein the tip-to-base length is between 1.0 meters and 1.5 meters. 
     
     
         5 . The wedge-shaped vortex generator of  claim 1 , wherein the base bottom width is between 0.5 meters and 1.0. 
     
     
         6 . The wedge-shaped vortex generator of  claim 1 , wherein the height of the body is between 20% and 40% of a local boundary layer thickness at the mounting location on the hull. 
     
     
         7 . The wedge-shaped vortex generator of  claim 1 , wherein the upper face is convex in a longitudinal direction from the tip to the base. 
     
     
         8 . The wedge-shaped vortex generator of  claim 1 , wherein the monolithic body is formed from a corrosion-resistant metal or composite material. 
     
     
         9 . The wedge-shaped vortex generator of  claim 1 , wherein the base face is configured for direct attachment to a marine hull using mechanical fasteners or welding. 
     
     
         10 . The wedge-shaped vortex generator of  claim 1 , wherein at least one dimension of the body is scaled according to a boundary layer thickness scaling factor. 
     
     
         11 . A vortex generator system for reducing hydrodynamic drag in a marine vessel, comprising:
 a hull;   a plurality of wedge-shaped vortex generators affixed to the hull, each vortex generator comprising:
 a monolithic body having an upper face with a convex curvature, a base face, a rear face, and a pair of laterally opposed side faces, wherein the body is defined by a wedge angle, a wedge elevation angle, a tip-to-base length, and a base bottom width; 
 wherein the plurality of vortex generators are circumferentially arranged around the hull at a predetermined longitudinal position relative to the flow detachment region, and are configured to generate streamwise vortices that re-energize the boundary layer, delay flow separation, and reduce form drag on the hull. 
   
     
     
         12 . The vortex generator system of  claim 11 , wherein the plurality of vortex generators are spaced circumferentially around the hull at uniform intervals. 
     
     
         13 . The vortex generator system of  claim 11 , wherein the monolithic body of each vortex generator is formed from a corrosion-resistant material selected from the group consisting of stainless steel, aluminum alloys, and composite materials. 
     
     
         14 . The vortex generator system of  claim 11 , wherein the plurality of vortex generators are affixed to the hull using mechanical fasteners, welding, or adhesive bonding. 
     
     
         15 . The vortex generator system of  claim 11 , wherein the longitudinal position of the plurality of vortex generators is determined relative to a point of flow detachment on the hull using a data-driven optimization methodology. 
     
     
         16 . The vortex generator system of  claim 11 , wherein the dimensions of each vortex generator are scaled according to a boundary layer thickness scaling factor. 
     
     
         17 . The vortex generator system of  claim 11 , wherein the number of wedge-shaped vortex generators is calculated as a ratio of a function of a circumference of the hull at the mounting location divided by a base width of an individual vortex generator. 
     
     
         18 . A computer-implemented method for optimization of a vortex generation system, comprising:
 receiving one or more models of the vortex generation system;   iteratively analyzing the one or more models utilizing a computational fluid dynamics analysis to determine one or more performance parameters for each of the one or more models;   comparing the one or more performance parameters of each of the one or more models;   selecting at least one model having a performance parameter of the one or more performance parameters exceeding a first threshold;   optimizing one or more dimensions of the at least one model, wherein in the optimizing further comprising:
 iteratively, varying the one or more dimensions of the at least one model; and 
 testing the varied one or more dimension resulting in at least one performance characteristic for each of the one or more dimensions; and 
   outputting, the one or more dimensions having the at least one performance characteristic exceeding a second threshold.