Commonly proposed ocean wave energy converters (OWEC) use inefficient and maintenance demanding intermediate hydraulic and pneumatic systems. We propose a novel rotary direct-drive OWEC that eliminates these intermediate stages. The new device employs a contactless force transmission system (CFTS) comprising a “piston” and a “cylinder” and a ball screw to...
The goal of this study was to develop an understanding of the nature of surge wave loading on
wood framed residential structures for a variety of building configurations and test conditions.
The objectives of the study were: (1) to measure forces on a 1/6th scale wood framed
residential structure, (2)...
Recently, the concept of performance based design has become popular for many types of structures, including port facilities under seismic loading. For the case of pile-supported wharves, the level of performance is generally estimated using the displacement capacity of the structure. Therefore, understanding soil-pile interaction is one of the most...
Fluid-structure interaction (FSI) is an interesting and challenging interdisciplinary area comprised of fields such as engineering- fluids/structures/solids, computational science, and mathematics. FSI has several practical engineering applications such as the design of coastal infrastructure (such as bridges, levees) subjected to harsh environments from natural forces such as tsunamis, storm surges,...
This thesis investigates the applicability of the finite element method to model wave energy converter (WEC) hydroelasticity using LS-DYNA. The proposed methodology uses the Arbitrary Lagrangian-Eulerian formulation to model Fluid-Structure Interaction (FSI) between the WEC and the fluid elements. This formulation allows for time-domain modeling of higher order effects such...
Since 2004 there have been multiple devastating tsunamis around the globe triggered by large magnitude earthquakes; with the most recent being the Tohoku, Japan tsunami in March 2011. These tsunamis have caused significant loss of life and damage to the coastal communities impacted by these powerful waves. The resulting devastation...
A numerical model for the simulation of fully-coupled fluid-structure
interaction is developed in this study. In modeling the fluid, the Reynolds
Averaged Navier-Stokes equations are solved for an incompressible viscous
fluid field and a k-ε model is employed for turbulence computations.
Hydrodynamic forces obtained by the integration of the fluid...
As part of a research program to study the transitional region of N=88
isotones, ¹⁵²Tb was produced by the reaction ¹⁵¹Eu(α,3n)¹⁵²Tb in the 88" cyclotron
located at LBNL. Gamma-ray spectroscopy of the radiation emitted from excited
¹⁵²Gd following the β⁺ decay of ¹⁵²Tb has been performed using an array of...
Complex oscillations including chaotic motions have been identified in off-shore and submerged mooring systems characterized by nonlinear fluid-structure interactions and restoring forces. In this paper, a means of controlling these nonlinear oscillations is addressed. When applied, the controller is able to drive the system to periodic oscillations of arbitrary periodicity....