APPENDIX D 

 FLOATING BREAKWATER ANALYSIS 



1. Purpose of the Program . 



Computer program BRK2D performs a performance analysis for two- 

 dimensional floating breakwaters of arbitrary cross section. This ana- 

 lysis includes predictions of the hydrodynamic coefficients, the dyna- 

 mics and mooring line forces. 



2. Program Description . 



Program BRK2D is written using both FORTRAN II and FORTRAN IV 

 statements. 



The program consists of the main program BRK2D and the subroutines 

 COEFF, COMP, PHYSCL, POTOUT, DYNAMC, MORTEN, CPV, LNEQF. 



The subroutines COEFF and COMP calculate the quantities needed to 

 formulate the linear equations for the velocity potential. COMP calls 

 on LNEQF to solve these linear simultaneous equations . 



Subroutine PHYSCL calculates the physical quantities including ad- 

 ded-mass and damping coefficients and surface elevations per unit ampli- 

 tude of motion. 



CPV is a subroutine which evaluates the Cauchy principal value 

 integral in the Green function. 



LNEQF is a packaged subroutine to solve simultaneous linear equa- 

 tions using the Gaussian reduction method. 



3. Type of Computer and Peripherals . 



BRK2D was written for use on the CDC 6400 computer. It uses about 

 55000g words of memory. No peripherals other than the card reader, line 

 printer and card punch are required. 



4. Input Data . 



The first cards in the data deck are label cards for the output. 

 These are shown in the example input in Table D-1 for the example and 

 are not included here. Following these cards, the input for BRK2D is: 



Card #1 - Title card. Format (8A10) . 



80 alphanumeric characters. 

 Card #2 - Logical control card. Format (5110,615). 



N = Number of straight line segments used to fit the hull. 



NW = Number of points on the free surface where wave 

 height is to be computed. 



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