Frictional Resistance of Antifouling Coating Systems

Abstract : An experimental study has been made to compare the frictional resistance of several ship hull coatings in the unfouled, fouled, and cleaned conditions. Hydrodynamic tests were completed in a towing tank using a flat plate test fixture towed at a Reynolds number (Re(L)) range of 2.8 x 10(6) - 5.5 x 10(6) based on the plate length and towing velocity. The results indicate little difference in frictional resistance coefficient (C(F)) among the coatings in the unfouled condition. Significant differences were observed after 287 days of marine exposure, with the silicone antifouling coatings showing the largest increases in C(F). While several of the surfaces returned to near their unfouled resistance after cleaning, coating damage led to significant increases in C(F) for other coatings. The roughness function DeltaU(+) for the unfouled coatings showed reasonable collapse to a Colebrook-type roughness function when the centerline average height (k = 0.17R(alpha)) was used as the roughness length scale. Excellent collapse of the roughness function for the barnacle fouled surfaces was obtained using a new roughness length scale based on the barnacle height and percent coverage.

[1]  Brain Butterworth.  Biofilm Growth and Hydraulic Performance , 1981 .

[2]  Michael P. Schultz,et al.  The Relationship Between Frictional Resistance and Roughness for Surfaces Smoothed by Sanding , 2002 .

[3]  M Atlar,et al.  The Measurement of the Drag Characteristics of Tin-free Self-polishing Co-polymers and Fouling Release Coatings Using a Rotor Apparatus , 2003, Biofouling.

[4]  I. L. Singer,et al.  Mechanical factors favoring release from fouling release coatings , 2000, Biofouling.

[5]  G. Swain,et al.  The influence of biofouling adhesion and biotic disturbance on the development of fouling communities on non‐toxic surfaces , 1998 .

[6]  J. Spurk.  Boundary Layer Theory , 2019, Fluid Mechanics.

[7]  C Grigson,et al.  DRAG LOSSES OF NEW SHIPS CAUSED BY HULL FINISH , 1992 .

[8]  R. Townsin.  The Ship Hull Fouling Penalty , 2003, Biofouling.

[9]  M. Atlar,et al.  Considering the use of alternative antifoulings: the advantages of foul-release systems , 2000 .

[10]  Robert J. Moffat,et al.  Describing the Uncertainties in Experimental Results , 1988 .

[11]  W. G. Steele,et al.  Engineering application of experimental uncertainty analysis , 1995 .

[12]  A. Musker.  Universal Roughness Functions for Naturally-Occurring Surfaces* , 1980 .

[13]  崇夫 乾.  Resistance Experiments on the "Lucy Ashton", : Part I-Full-Scale Measurements , 1953 .

[14]  M P Schultz,et al.  Three Models to Relate Detachment of Low Form Fouling at Laboratory and Ship Scale , 2003, Biofouling.

[15]  Lars Larsson,et al.  An experimental/numerical approach for evaluating skin friction on full-scale ships with surface roughness , 2003 .

[16]  M. Schultz,et al.  Comparison of three roughness function determination methods , 2003 .

[17]  Michael A Champ,et al.  Economic and environmental impacts on ports and harbors from the convention to ban harmful marine anti-fouling systems. , 2003, Marine pollution bulletin.

[18]  M. Schultz,et al.  Variation in adhesion strength of Balanus eburneus, crassostrea virginica and hydroides dianthus to fouling‐release coatings , 2001 .

[19]  Gerard S. Bohlander,et al.  The National Shipbuilding Research Program, 1992 Ship Production Symposium Proceedings, Paper No. 3A-1: Microbial Biofilm Effects on Drag - Lab and Field , 1992 .

[20]  F. Clauser.  Turbulent Boundary Layers in Adverse Pressure Gradients , 1954 .

[21]  Peter Bradshaw.  A note on “critical roughness height” and “transitional roughness” , 2000 .

[22]  M. Schultz,et al.  The testing and evaluation of non-toxic antifouling coatings. , 1996, Biofouling.

[23]  Karen A. Flack,et al.  Turbulent Boundary Layers Over Surfaces Smoothed by Sanding , 2002 .

[24]  R. A. Antonia,et al.  Surface roughness effects in turbulent boundary layers , 1999 .

[25]  M. Schultz,et al.  The effect of biofilms on turbulent boundary layers , 1999 .

[26]  P S Granville,et al.  THREE INDIRECT METHODS FOR THE DRAG CHARACTERIZATION OF ARBITRARILY ROUGH SURFACES ON FLAT PLATES , 1987 .

[27]  James Williamson,et al.  THE LAWS OF FLOW IN ROUGH PIPES , 1951 .

[28]  A F Molland,et al.  AN INVESTIGATION INTO THE VARIATION OF SHIP SKIN FRICTIONAL RESISTANCE WITH FOULING , 1985 .

[29]  Michael P. Schultz.  Turbulent Boundary Layers on Surfaces Covered With Filamentous Algae , 2000 .

[30]  H Lackenby.  The Thirty-Fourth Thomas Lowe Gray Lecture: Resistance of Ships, with Special Reference to Skin Friction and Hull Surface Condition: , 1962 .