Calculation of Water Oscillation in Coastal Harbors HARBS and HARBD User's Manual

This report briefly describes a hybrid element model for calculating linear wave oscillation in and near coastal harbors. The model includes bottom friction and boundary absorption. The bottom friction is assumed to be proportional to flow velocity with a phase difference. The boundary absorption adopts a formulation similar to the impedance conditions in acoustics, and it is expressed in terms of wave number and reflection coefficient of the boundary. In the model the entire domain is divided into the near and far regions by an artificially semicircular boundary. The near regions should encompass the harbor and the concerned marine structure and bathymetry. The far region is assumed to have a straight coastal line and a constant water depth. A conventional finite element approximation is used for the near regions, while an analytical solutions is used for the far region. A variational principle with a proper functional is established to ensure these matching conditions are satisfied along the artificial semicircular boundary. HARBS and HARBD computer programs are based on the hybrid element model. General features of HARBS and HARBD are described in this report, and data input requirements are presented in detail. Guidelines for use of the programs to specific field problems are given and illustrated with a rectangular harbor. The programs are written in FORTRAN V, and a complete listing of the programs is included. The formatted input data and a sample of the program output for the rectangular harbor are also included.