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Mexico unveils energy reforms

Mexican President Enrique Peña Nieto announced his plans to reform Mexico’s energy industry in an effort to ease restrictions on foreign investment.

NOAA: Atlantic hurricane season update

George P. Mitchell passed away at the

The US National Oceanic and age of 94 on July 26th.

Atmospheric Administration

He was a pioneer in (NOAA) predicts a busy hydraulic fracturing

Atlantic hurricane season and transformed the with 13 to 19 named natural gas industry. storms, with up to fve

See more on Mitchell turning into major events. at OilOnline.com

DNV SOFTWARE – A LEADING PROVIDER OF SOFTWARE FOR RISK

WHITE PAPER

Title: Hydrodynamic analysis of offshore structures

AUTHOR: Torgeir Kirkhorn Vada, DNV Software

DATE: April 2013

Introduction

White Papers

This paper describes the role of a linear frequency domain analysis for o?shore structures, and some of the important aspects that must be addressed when doing such an analysis. The two main challenges in this analysis, in additon to creatng a good quality panel model, are: How to include the viscous e?ects How to handle the mooring system

Both of these will be discussed in some detail. The requirements to the panel model should be quite well known so that will not be described.

Critical asset performance Hydrodynamic analysis

General

For o?shore structures both FLS (Fatgue Limit State) and ULS (Ultmate Limit State) analyses are normally carried out. The overall analysis process is shown in ?gure 1.

The main purpose of the hydrodynamic analysis will in many cases be to compute the loads to be applied in a following structural analysis. These loads are typically: standards (CAPS) development of offshore structures

Inerta load due to the acceleraton of the vessel

Pressure load on the outer hull and on compartment walls if there is an internal ?uid

Line loads on beam elements and loads from risers and mooring lines

In additon, global loads are ofen computed. Also the motons may be of signi?cant interest on their own, in partcular for computng relatve moton/air gap. for offshore reliability

DNV Software’s Torgeir

Kirkhorn Vada describes the

Life Cycle Engineering, Inc. discusses the role of a linear frequency domain process involved in developing CAPS for integration into a analysis for offshore structures.

safety and environmental management system (SEMS).

Register Now

New Orleans

SPE Annual Technical Conference and Exhibition 30 September–2 October » Ernest N. Morial Convention Center

New Orleans, Louisiana, USA » www.spe.org/atce oedigital.com September 2013 | OE 13 013_OE9013_oedigital.indd 13 8/18/13 8:05 PM