Evaluation of an Approximate Method for Incorporating Floating Docks in Harbor Wave Prediction Models

Abstract

Computer models based on the two-dimensional (2-D) elliptic mild-slope equation are nowadays routinely used in harbor engineering applications. However, structures like floating breakwaters and docks, which are often encountered in the modeling domain, render the problem for locally three-dimensional model and hence are problematic in incorporate in a 2-D model. Tsay and Liu (Applied Ocean Research. 1983. Vol 5(1): 30-37) proposed a highly simplified but approximate approach that does not violate the overall two dimensionality of the problem. The validity of their approach is examined in detail, and it is found that although their approximation provides results with the correct trend, the actual solutions deviate considerably from the theoretical solutions. We have developed correction factors that may be used to produce more reliable results using the framework of Tsay and Liu. Application of the resulting method to a harbor in Alaska shows that docks in the harbor distort the wave field considerably and create a reflective pattern that has the potential to affect navigation safety in some areas. A by-product of this paper consists of plots of transmission coefficients for waves propagating past rectangular and cylindrical floating objects of infinite extent for a wide range of conditions encountered in practice. Such transmission coefficients are at present readily available in the published literature for selected cases only.

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Document Details

Document Type
Technical Report
Publication Date
Nov 25, 2005
Accession Number
ADA483154

Entities

People

  • Dongcheng Li
  • Jerry Ramsden
  • Vijay Panchang
  • Zeki Demirbilek
  • Zhaoxiang Tang

Organizations

  • Engineer Research and Development Center

Tags

Communities of Interest

  • Ground and Sea Platforms
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Army Corps Of Engineers
  • Boundaries
  • Breakwaters
  • Civil Engineering
  • Coastal Engineering
  • Coefficients
  • Computers
  • Deep Water
  • Engineering
  • Engineers
  • Equations
  • Floating Docks
  • Geometry
  • Harbors
  • Three Dimensional
  • Two Dimensional
  • Wave Propagation

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Coastal and Marine Engineering/Sediment Transport/Hydraulic Engineering
  • Systems Analysis and Design