Surface coating for reduction of aerodynamic noise and vibrations

Abstract

A coating apparatus for the reduction of aerodynamic noise and vibrations. The coating apparatus is configured to include a group of fibrillar structures, wherein each fibrillar structure is configured with a diverging tip so that the coating reduces the size of and shifts downstream, a separation bubble, and modulates large-scale recirculating motion. Each fibrillar structure can be configured as a cylindrical micropillar. The group of fibrillar structures can be configured as a group of uniformly distributed cylindrical micropillars (e.g., one or more micropillar arrays). The surface coating is effective in reducing the separation bubble and displacing the separation bubble downstream. The coating facilitates a reduction in noise (e.g., aerodynamic noise) and vibrations due to the reduction in the size of the separation bubble.

What is claimed is: 
     
         1 . A coating apparatus, comprising
 a coating comprising a plurality of fibrillar structures, wherein each fibrillar structure among said plurality of fibrillar structures is configured with a diverging tip so that said coating reduces a size of and shifts downstream, a separation bubble, and modulates large-scale recirculating motion.   
     
     
         2 . The apparatus of  claim 1  wherein said coating facilitates a reduction in noise and vibrations due to said reduction in said size of said separation bubble. 
     
     
         3 . The apparatus of  claim 1  wherein said coating facilitates a reduction in drag. 
     
     
         4 . The apparatus of  claim 1  wherein said coating comprises an antifouling coating. 
     
     
         5 . The apparatus of  claim 1  wherein each fibrillar structure among said plurality of fibrillar structures comprises a cylindrical micropillar and said plurality of fibrillar structures comprises a plurality of uniformly distributed cylindrical micropillars. 
     
     
         6 . The apparatus of  claim 1  wherein said coating is configured to function under a dry condition. 
     
     
         7 . The apparatus of  claim 1  wherein said coating is configured to function under a wet condition. 
     
     
         8 . The apparatus of  claim 1  wherein said coating mitigates flow separation without a noticeable increase in a production of turbulent kinetic energy. 
     
     
         9 . The apparatus of  claim 1  wherein said coating comprises a microsurface coating that shifts a separation point downstream and reduces an area of negative flow. 
     
     
         10 . The apparatus of  claim 1  wherein said coating relies on a generation of distributed wall-normal perturbations. 
     
     
         11 . The apparatus of  claim 1  wherein said coating comprises a micropillar coating comprising said plurality of fibrillar structures. 
     
     
         12 . A coating apparatus, comprising
 a coating that facilitates a reduction in noise and vibrations, said coating comprising a plurality of fibrillar structures, wherein each fibrillar structure among said plurality of fibrillar stuctures is configured with a diverging tip so that said coating reduces a size of and shifts downstream, a separation bubble, and modulates large-scale recirculating motion and wherein said each fibrillar structure among said plurality of fibrillar structures comprises a cylindrical micropillar, said plurality of fibrillar structures comprising a plurality of uniformly distributed cylindrical micropillars and wherein said coating facilitates said reduction of said noise and vibrations due to said reduction in said size of said separation bubble.   
     
     
         13 . The apparatus of  claim 12  wherein said coating further facilitates a reduction in drag. 
     
     
         14 . The apparatus of  claim 12  wherein said coating further facilitates a prevention of or a reduction in biofouling. 
     
     
         15 . The apparatus of  claim 12  wherein said coating is configured to function under either wet or dry conditions. 
     
     
         16 . The apparatus of  claim 12  wherein said coating comprises a bio-inspired surface coating. 
     
     
         17 . The apparatus of  claim 12  wherein said coating mitigates flow separation without a noticeable increase in a production of turbulent kinetic energy. 
     
     
         18 . The apparatus of  claim 12  wherein said coating comprises a microsurface coating that shifts a separation point downstream and reduces an area of negative flow. 
     
     
         19 . The apparatus of  claim 12  wherein said coating relies on a generation of distributed wall-normal perturbations. 
     
     
         20 . A method of configuring a coating apparatus, said method comprising:
 providing a coating comprising a plurality of fibrillar structures;   configuring each fibrillar structure among said plurality of fibrillar stuctures with a diverging tip so that said coating reduces a size of and shifts downstream, a separation bubble, and modulates large-scale recirculating motion, wherein said coating facilitates a reduction in noise and vibrations due to said reduction in said size of said separation bubble, and further facilitates a reduction in drag.