Accession Number : ADA266820


Title :   Nonlinear Wave Forces on Large Ocean Structures


Descriptive Note : Final rept. Oct 91-Sep 92,


Corporate Author : NAVAL CIVIL ENGINEERING LAB PORT HUENEME CA


Personal Author(s) : Huang, Erick T


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a266820.pdf


Report Date : Apr 1993


Pagination or Media Count : 53


Abstract : This study explores the significance of second-order wave excitations on a large pontoon and tests the feasibility of reducing a nonlinear free surface problem by perturbation expansions. A simulation model has been developed based on the perturbation expansion technique to estimate the wave forces. The model uses a versatile finite element procedure for the solution of the reduced linear boundary value problems. This procedure achieves a fair compromise between computation costs and physical details by using a combination of 2D and 3D elements. A simple hydraulic model test was conducted to observe the wave forces imposed on a rectangle box by Cnoidal waves in shallow water. The test measurements are consistent with the numerical predictions by the simulation model. This result shows favorable support to the perturbation approach for estimating the nonlinear wave forces on shallow draft vessels. However, more sophisticated model tests are required for a full justification. Both theoretical and experimental results show profound second-order forces that could substantially impact the design of ocean facilities.


Descriptors :   *OCEAN WAVES , *OFFSHORE STRUCTURES , *PONTOONS , TEST AND EVALUATION , SIMULATION , PREDICTIONS , TWO DIMENSIONAL , STIFFNESS , SURFACES , SHALLOW WATER , MODEL TESTS , FLOATING PLATFORMS , FLOATING BODIES , HYDRAULIC MODELS , HEIGHT , OCEANS , PERTURBATIONS , BOUNDARY VALUE PROBLEMS , DIFFRACTION , THREE DIMENSIONAL , COSTS , EXCITATION , MODELS , MEASUREMENT , COMPUTATIONS


Subject Categories : Physical and Dynamic Oceanography
      Marine Engineering


Distribution Statement : APPROVED FOR PUBLIC RELEASE