سعید جامعی

Floating platform in the greater influence of environmental sea forces rather Fixed platforms, So that all exploration, drilling and extraction Operations by platforms, are affected by different degrees of freedom and the movements of the structure. Therefore, selecting the appropriate parameters in the design of these platforms can help to decrease dynamical response to environmental hydrodynamics stimulation and increase efficiency in all stages of the platform. The first step in floating structure design is analysis and investigating structural dynamic response against environmental conditions, and design is successful when we try to minimize dynamic response derived from environmental condition with choosing the appropriate parameters and geometric characteristics. Therefore, in this thesis we try to take advantage of software capabilities MOSES, the effect of different geometric parameters of semi-submersible platforms (in particular Amir Kabir semi-submersible rig), will be discussed the effects of essential parameters on platform’s response, to obtained the appropriate geometric standards for reduce motion response. In this regard, the Amir Kabir semi-submersible rig simulated in the MOSES software and then derived charts, scale all six degrees of freedom at different angles "0" ^?,?"30" ?^?,?"45" ?^?,?"60" ?^?,?"090" ?^?, Then, by comparing the output charts and results by Norwegian companies’ charts that manufactured the platform will be checked the authenticity of simulation, and then change the basic parameters and comparison the platform models charts operator’s scale has changed with the original model, positive change that reduces the structural dynamic response to environmental forces were identified and analyzed.