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Issue link: http://sea-technology.epubxp.com/i/726897
34 st / September 2016 www.sea-technology.com reduce the potential accumulation of toxic and flammable gases and provide indications of potential vapor cloud ex- plosion consequences; the helideck im- pairment, which can impact helicopter operations due to hot turbine exhaust gases, affecting both general operations and potential emergency operations; the wind chill, which can affect the ability of personnel to work on the platform, particularly important in cold climates and extreme weather areas where work- ing conditions can influence the num- ber of personnel required for operation; the lifeboat drift-off direction, which can impact the safety of the crew in an emergency situation; and the hydrody- namic drag, which can affect tendon fatigue life, hull integrity and structural design requirements. T echnical safety in the oil and gas industry is of paramount importance. With most tension leg platforms (TLP) being geographi- cally remote, costing upward of $3.5 billion, containing a multi- tude of process and operational hazards, and having confined per- sonal space on board, it is crucial to minimize the risks to people and assets. This can be achieved through the process of inherently safe design (ISD), in which techni- cal safety has direct influence on the design, from concept through commissioning. The platform orientation is one design aspect that can play a signifi- cant role in the ISD process, limiting the adverse effects should an incident occur. Traditionally, the platform ori- entation has been determined by en- gineering judgment, heavily weighted by past experiences. While this approach initially appears to be time- and cost-ef- fective, it has the potential to lead to an unideal design solution that could cause safety and operational issues to go unad- dressed and increased costs in later design stages. This article will discuss how the orientation and layout of an offshore platform can have a significant impact in developing a better and more informed de- sign, keeping with ISD principles. A case study involv- ing an operator near the Falkland Islands will be discussed where CD-adapco STAR-CCM+ was integrated with addition- al analysis tools to optimize the orientation of a fixed offshore platform. It will demonstrate a technique to find the optimum platform orientation, i.e., the one that results in the best de- sign compromise between specified parameters. Optimization Parameters The parameters considered for the optimization study were as follows: the natural ventilation (wind), which can CFD for Optimizing Tension Leg Offshore Platform Orientation Five Parameters for Better Design By Gerard Reynolds • Andrew Staszak n (Top) The aim of this study was to find the optimum theta, or the angle between True North and Platform North, based on a set of parameters. (Bottom) The offshore platform is powered by burning some of the gases it produces. The exhaust outlets need to be positioned in such a way that the exhaust fumes minimize potential impairment to the helideck operational zone throughout the year.