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Due to the very large expanse of warm water in the northwest Pacific Ocean, typhoons are stronger and occur more frequently than hurricanes. In addition, there is usually a lack of unified high-resolution data of wind fields and bathymetry since multiple countries can be influenced by a typhoon. Therefore, we use multiple-resolution data in an adaptive simulation for typhoon-induced waves. Higher-resolution data are obtained from the government of Taiwan and are used for the area around Taiwan. In the other area, lower resolution data are adopted from the National Oceanic and Atmospheric Administration of the United States. An adaption criterion is implemented such that the highest resolution numerical grids move with the typhoon in a large-scale simulation. The numerical results obtained by the large-scale simulation with multiple-resolution wind fields are improved over those obtained by a smaller scale simulation with the higher resolution wind field at buoys near Taiwan. In addition, the large-scale simulation also provides results for buoys where the higher resolution wind field is not available. In addition, a speedup of fourfolds by the dynamic adaption model over the partially uniform grid one is demonstrated. [ABSTRACT FROM AUTHOR]

Analytical particular solutions of the augmented polyharmonic spline (APS) associated with the polyharmonic and poly-Helmholtz operators and their products were derived by Tsai et al. (Eng Anal Bound Elem 33 (2009), 514). In addition, it has been mentioned that the particular solution associated with a coupled system of partial differential equations (PDEs) can be derived from the prescribed solutions by using the Hörmander operator decomposition technique. In this article, this derivation procedure is demonstrated via Mindlin thick-plate problems, which are governed by a coupled system of three second-order PDEs. Analytical particular solutions of displacements, shear forces, and bending or twisting moments corresponding to the polyharmonic spline and monomials are all explicitly derived. These particular solutions are validated using numerical examples. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2011 [ABSTRACT FROM AUTHOR]

The evaluation of wave-induced seabed stability around a submerged breakwater is particularly important for coastal engineers involved in design of the foundation of breakwaters. Unlike previous studies, a mesh-free model is developed to investigate the dynamic soil response around a submerged breakwater in this study. Both regular and irregular wave loadings are considered. The present model was validated against the previous experimental data and theoretical models for both regular and irregular waves. Parametric study shows the regular wave-induced liquefaction depth increases as wave period and wave height increase. The seabed is more likely to be liquefied with a low degree of saturation and soil permeability. A similar trend of the effects of wave and seabed characteristics on the irregular wave-induced soil response is found in the numerical examples. [ABSTRACT FROM AUTHOR]

The evaluation of the wave-induced seabed instability around a submarine pipeline is particularly important for coastal engineers involved in the design of pipelines protection. Unlike previous studies, a meshfree model is developed to investigate the wave-induced soil response in the vicinity of a submarine pipeline. In the present model, Reynolds-Averaged Navier-Stokes (RANS) equations are employed to simulate the wave loading, while Biot's consolidation equations are adopted to investigate the wave-induced soil response. Momentary liquefaction around an offshore pipeline in a trench is examined. Validation of the present seabed model was conducted by comparing with the analytical solution, experimental data, and numerical models available in the literature, which demonstrates the capacity of the present model. Based on the newly proposed model, a parametric study is carried out to investigate the influence of soil properties and wave characteristics for the soil response around the pipeline. The numerical results conclude that the liquefaction depth at the bottom of the pipeline increases with increasing water period (T) and wave height (H), but decreases as backfilled depth ( H b ), degree of saturation ( S r ) and soil permeability (K) increase. [ABSTRACT FROM AUTHOR]