مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

تأثیر اندازه بویه بر پاسخ فرکانسی و زمانی در سیستم مهار کاتناری سکوی نیمه مغروق

نویسندگان
1 عضو هیات علمی
2 دانشکده مهندسی دریا، دانشگاه صنعتی امیرکبیر، تهران، ایران
3 دانشگاه صنعتی امیرکبیر
چکیده
با توجه به کاهش منابع طبیعی آب های کم عمق، توسعه اکتشاف و تولید به سمت منطقه آب های عمیق و عمیق تر منتقل شده است. انواع سازه های شناور وقتی به عنوان سکوهای تولیدی مشغول به عملیات هستند نیازمند مهار می باشند. استفاده از بویه در سیستم مهار کاتناری برای اعماق زیاد دریا می تواند موجب کاهش وزن و شعاع مهار گردد. در این مقاله پاسخ دینامیکی سکوی نیمه شناور امیرکبیر تحت تأثیر نیروهای باد و امواج در حوزه فرکانس و حوزه زمان محاسبه گردیده است. طیف موج جانسوآپ و طیف باد API به عنوان شرایط محیطی در نظر گرفته شده است و همچنین تأثیر اندازه بویه بر روی پاسخ حرکت سکوی نیمه شناور بررسی شده است. پاسخ دینامیکی سکوی نیمه شناور با استفاده از معادلات موریسون و تئوری تفرق محاسبه گردیده است و هر کابل مهار به صورت زنجیره ای از المان های موریسون تحت تأثیر نیروی خارجی مدل شده است. نتایج بدست آمده از نرم‌افزار آکوا در حوزه زمان و حوزه فرکانس نشان می دهد که با افزایش اندازه بویه می تواند باعث افزایش حرکات سکوی نیمه شناور شده و در عوض باعث کاهش تنش های وارده بر کابل می باشد.
کلیدواژه‌ها

عنوان مقاله English

Effects of Buoy size on the frequency and time response in catenary mooring system of the semi-submersible platform

نویسندگان English

Morteza Dardel 1
Hamidreza Ghafari 2
seyed vahid sepehr mousavi 3
1 Department of Mechanical Engineering, Babol Noshirvani University of Technology, P.O. Box 484, Postal Code: 47148-71167, Shariati Street, Babol, Mazandaran, Iran. dardel@nit.ac.ir.
2 Department of Maritime Engineering, Amirkabir University of Technology, Tehran, Iran
3 amirkabir university of technology
چکیده English

Due to the depletion of shallow water resources, the development of exploration and production has shifted towards the deep and ultra-deep water region. The types of floating platforms are all need to be moored when they are working as production platforms. Applying buoys to the catenary mooring system in deep water may reduce part of the weight and radius of a mooring. In this article, Dynamic responses of the Amirkabir semi-submersible platform was obtained under the combination of wind and wave loads in frequency domain and time domain simulation calculated. The JONSWAP wave spectrum and API wind spectrum are considered as environmental conditions .and also the effects of buoy size on the semisubmersible motion response is investigated. Dynamic responses of the semi-submersible platform determine by using the Morison equation and diffracting theory in AQWA ANSYS software and each dynamic mooring line is modeled as a chain of Morison-type elements subjected to various external forces. The obtained result from AQWA ANSYS in time and frequency domain shows that increasing buoy size, could increase motions of the semisubmersible platform but instead could decreasing the mooring line tension.

کلیدواژه‌ها English

Semi-submersible
buoy
catenary mooring system
three-dimensional radiation/diffraction theory
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