Numerical and Experimental Investigations on Deepwater CALM Buoys Hydrodynamics Loads

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractPrincipia R.D. is the leader of the CALM BUOY JIP, which purposeis to study the behavior of deepwater CALM Buoys systems. The final objective is to provide guidelines for the analysis of deepwater offloading systems covering the main aspects related to the OOL/mooring lines fatigue analysis. Most of the attention is focused on the buoy hydrodynamics using both experimental campaigns and numerical investigations (full and model scales). Captive tests and forced oscillations tests at scale of 1/25 were performed with different skirt dimensions and drafts characteristic of a typical buoy.A new methodology and formulation is derived for damping estimation which is a key point of the analysis. The various damping formulations are implementedand tested in a fully coupled buoy / lines finite element solver. The results are validated against experimental measurememts in regular and irregular waves. Recommendations are deduced on the "model of model" approach classicaly used for model tests.Finally, use of CFD calculations to replace forced oscillations tests is also explored through comparisons with model tests. CFD appears to be a reliable tool to assess scale effects and to compare buoy geometries.

Review on the design and mechanics of bonded marine hoses for Catenary Anchor Leg Mooring (CALM) buoys

“…However, different hose problems have been solved from these developed hoses concepts, which led to advances in single point moorings (Sao et al 1987;Wichers 2013;Obokata 1987;Obokata & Nakajima 1988) Submitted to: Elsevier's Ocean Engineering Journal and various forms of offloading hose systems (Cao Q. et al 2017(Cao Q. et al , 2018Amaechi et al 2019aAmaechi et al , 2019b. These were achieved by different studies, such as scaled models (Ricbourg et al 2006;Cunff et al 2007;Ryu et al 2006;O'Donoghue & Halliwell 1990;Quash & Burgess 1979;Pinkster & Remery 1975), experiment on test rigs (Tschoepe & Wolfe 1981;Young et al 1980), field measurements (Brady et al 1974;Saito et al 1980;Lebon & Remery 2002), mathematical modelling (Brown & Elliott 1988;Zhang et al 2015;Bree et al 1989;Huang & Leonard 1989;Brown 1985a;Brown 1985b;Donoghue & Halliwell 1990) and numerical simulations ( Duggal & Ryu 2005;Roveri et al 2002;Amaechi et al 2021i, 2021j, 2021k, 2021l). In subsequent sections, more discussion on marine hoses will be conducted.…”

Experimental Study on Motion Characterisation of CALM Buoy Hose System under Water Waves

“…These hoses have some cons, ranging from a shorter service life, kinking, matrix cracking, damage from vessel motion, damage from hose response (snaking phenomenon and perturbations), damage from impact (line clashing), damage from disconnection (accidental operation) and vibration to other structural challenges [40][41][42][43][44]. On the other hand, the buoys have motion responses that are relatively due to the wave loads and hydrodynamic properties on the FOS [45][46][47][48][49][50]. In real-life applications of offloading and loading operations in offshore oil terminal systems are made of single point moorings (SPM), which are made up of three main mooring configurations: Articulated Single Point Moorings (ASPM), Single Anchor Leg Moorings (SALM) and Catenary Anchor Leg Moorings (CALM) [51][52][53][54][55].…”

Scientometric Review and Thematic Areas for the Research Trends on Marine Hoses

“…Additionally, both polymers and composites are potential materials that could be used to improve the performance of marine hoses. The hose materials are used to enhance the mechanical characteristics, longevity, fatigue resistance, and usability for marine applications [67][68][69][70][71][72][73][74][75][76][77]. Based on innovative designs, oil offloading lines (OOL) have found recent applications in deep water at offloading terminals [38][39][40][41]77].…”