مهندسی دریا
Reza Movahedinia; Mirabdolhamid Mehrdad; Saeed pourzeynali
Abstract
Jacket-type offshore platforms play an important role in oil and gas industries in shallow and intermediate water depths such as Persian Gulf region. Such important structures need accurate considerations in analysis, design and assessment procedures. Incremental wave analysis for performance-based assessment ...
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Jacket-type offshore platforms play an important role in oil and gas industries in shallow and intermediate water depths such as Persian Gulf region. Such important structures need accurate considerations in analysis, design and assessment procedures. Incremental wave analysis for performance-based assessment of jacket platforms is established in 2011 to estimate different limit states and accurate behavior of jacket platform against environmental wave loading. IWA can be appropriate substitute to current pushover practice. The IWA can estimate the collapse-prevention limit state of jacket platforms properly. In addition, an appropriate parameter for ultimate capacity of offshore platforms is introduced which is called Collapse Wave Height (CWH). The CWH can be utilized as a substitute to RSR parameter in the design and assessment of jacket platforms. In this paper, IWA is explained. IWA curves, collapse-prevention limit state and CWH for case study platform is calculated. Effect of deck mass and its distribution on CWH is examined.
مهندسی دریا
sajad sadr; Mohamad Hosein Khanzade
Abstract
According to recent advances in military science and electrical engineering on the one hand and on the other hand, subject of replacing diesel engines with electro motors (due to higher efficiency, less maintenance, better performance, better dynamics, etc.), this paper discuss about electric ships and ...
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According to recent advances in military science and electrical engineering on the one hand and on the other hand, subject of replacing diesel engines with electro motors (due to higher efficiency, less maintenance, better performance, better dynamics, etc.), this paper discuss about electric ships and simulation of the boat drives with electric motors. Since the construction of electro motors up to 1970th (which is the start point of Power Electronic that result in speed control of AC motors), the propulsion system hadn’t been use system uses electric motors. But after that, due to the high response rate, quick start, high efficiency, good reliability, easy maintenance and low cost ... Day by day the use of AC motors became more significant. Since Modeling and Simulation of vector control of AC motor for boat propulsion (with Load model) hasn’t been written as an detailed article, so the purpose of this paper is analyze of vector control performance of induction motor as vessels motor. The Contents of this article is this respect; after Introduction, various components of the propulsion system are discussed that with Load model will give propulsion system of vessel. In this paper after describe of vessel propulsion system, the vessel with electric propulsion motors has been discussed and finally an electric propulsion system for typical vessel is designed. The result of modeling and simulation of this project in conclusion part is discussed.