نوع مقاله: مقاله پژوهشی

نویسندگان

1 مربی، گروه عمران، دانشگاه بزرگمهر قائنات

2 استاد، بخش مهندسی عمران، دانشگاه شهید باهنر کرمان

3 دانش آموخته کارشناسی ارشد عمران

چکیده

در مطالعات پیشین، مدلسازی­ تجربی سکوی شناور از دو جهت دارای اهمیت بوده است: 1-  صحت­ سنجی روش­های عددی مورد استفاده در حل مسئله مورد نظر. 2- ساخت مدل آب­های عمیق با سیستم مهاری قطع شده. در این مطالعه پس از بدست آمدن ابعاد مناسب کابل قطع شده از روش عددی، به بررسی آزمایشگاهی رفتار هیدروالاستیک یک سکوی شناور تحت اثر نیروی موج پرداخته شد و در این راستا مطالعات تجربی و عددی اخیر مورد استفاده قرار گرفت. مدل با مقادیر بهینه مربوط به ابعاد سیستم مهار، تحت سه نوع موج سینوسی و دو طیف نامنظم با دامنه و پریودهای مختلف در دو عمق آبخور متفاوت قرار گرفته و مجموعا 36 تست تولید شد. بر اساس شرایط آزمایشگاهی برای مدلسازی آب­های عمیق، مقیاس یکصدوبیستم انتخاب شد. بمنظور برونیابی صحیح نتایج مدل سیستم مهاری در حالت قطع شده به نتایج عمق واقعی، روش دو مرحله­ ای هیبریدی (آزمایش و روش عددی آفلاین) استفاده شد و نتایج بدست آمده برای تعیین ابعاد لازم کابل سیستم مهاری مورد استفاده در آزمایشگاه،  بکار رفت. بر اساس یافته­ های قبلی، آزمایشات دریایی در مقیاس حدود یک پنجاهم مورد اطمینان بوده و برای مدل­های کوچکتر، صحت ­سنجی نتایج لازم بنظر می­رسد. در این راستا نتایج بدست آمده با یافته‌های مطالعات پیشین صحت سنجی شد که نشان از تایید مدلسازی سکو و نحوه مهاربندی آن در آزمایشگاه است.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Experimental Investigation of hydro-elastic behavior of a Semi-Submercible Platform by usage of hybrid model

نویسندگان [English]

  • S.H Shakib 1
  • M.J Khanjani 2
  • H Shojarastegari 3

1 bozorgmehr university of qaenat

چکیده [English]

In previous studies, experimental modeling of a semi-submersible platform has been significant from two aspects: 1- Validation of numerical methods used to solve the considered problem. 2- Setting up a deep water model using truncated mooring system. In this study, after obtaining the proper dimensions of truncated cables by usage of numerical method, experimental investigation of hydro-elastic behavior of a semi-submersible platform under the wave force was conducted and for this purpose, recent numerical and experimental studies were used. The model with optimal valuesrelated to mooring system dimensions was tested under three sine waves and two irregular spectrums with different amplitudes and periods in two various drafts and overall 39 tests were produced. According to laboratory conditions for deep water simulation, a 1:120 scale was selected. In order to correctly extrapolate the results of mooring system model in truncated condition to actual depth values, a two-stage hybrid method was used (model test and off-line numerical method) and the results were applied to determine the required dimensions for mooring systemcable used in laboratory. According to previous findings, marine experiments were accredited with scale of approximately 1:50 and the validation of results appeared necessary for smaller models. In this way, the obtained results were validated by findings of previous studies which demonstrate that the modeling of platform and its mooring method in the laboratory has been done properly.            
 

کلیدواژه‌ها [English]

  • Floating platform
  • Experimental model
  • hydro-elastic response
  • wave force
  • Mooring line

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