Experimental and Numerical of Sloshing Effect on Heave and Pitch Motions of FLNG Vessel

Recently the demand of sloshing analysis is rising for building FLNG (Floating Liquefied Natural Gas) vessel. This study considers the experimental and numerical observations on strongly nonlinear sloshing flows in ship motion. The FLNG (Floating Liquefied Natural Gas) vessel was considered to be rigid body supported by non-permanent pole with distributed spring damper. Based on the general equation of the ship motion in waves, and various wave amplitude, various heading, wave period and critical fluid level on the cargo tank period governing equation induced by sloshing were derived. Several physical issues are introduced in the analysis of sloshing flows, and the corresponding numerical models are described. To study the sloshing effects on ship motion, a ship motion program based on impulsive response function (IRF) is coupled with the developed numerical models for sloshing analysis. The results show that the nonlinearity of sloshing-induced forces and moments plays a critical role in the coupling effects.

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From diversity to inclusion: Woodside Energy's inclusion and diversity journey

The APPEA Journal ◽

10.1071/aj19228 ◽

2020 ◽

Vol 60 (2) ◽

pp. 473

Author(s):

Ruth Lyall

Keyword(s):

Natural Gas ◽

Oil And Gas ◽

Critical Role ◽

Liquefied Natural Gas ◽

Indigenous Australian ◽

Inclusion And Diversity ◽

The Way

Woodside is a leading natural gas producer in Australia, operating 6% of the global supply of liquefied natural gas. Woodside has been on an accelerated inclusion and diversity journey since 2015, with female and Indigenous Australian participation growing each year, and recognition through the Australian Workplace Equality Index as the oil and gas sector’s most LGBTI+-inclusive company in 2019.This paper sets out experiences and learnings from Woodside’s journey so far, including: the way Woodside uses measurable objectives to set expectations and increase accountability; why everyday people decisions matter; the critical role of inclusive, employee-driven networks to support under-represented groups, and also engage the broader workforce.

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MODEL ANALITIK SLOSHING TANGKI- MUAT PADA OLAH GERAK KAPAL FLOATING LIQUEFIED NATURAL GAS (FLNG) = ANALITICAL MODEL OF SLOSHING IN STORAGE TANK ON FLOATING LIQUEFIED NATURAL GAS (FLNG) SHIP MOTION

Majalah ilmiah Pengkajian Industri ◽

10.29122/mipi.v9i1.90 ◽

2015 ◽

Vol 9 (1) ◽

pp. 1-12

Author(s):

Luhut Tumpal Parulian Sinaga

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Natural Gas ◽

Numerical Simulations ◽

Computational Fluid Dynamic ◽

Fluid Dynamic ◽

Model Testing ◽

Liquefied Natural Gas ◽

Ship Motion ◽

Ocean Engineering

Studies on the effect of sloshing motion and heave coupling picth after receiving an external force wage varying wave energy and angular variation headings. This study will conduct a study of physical model testing with mooring configuration and MAT-LAB program of mathematical models free floating barge matika mechanism through numerical simulations and computational fluid dynamic (CFD). This riset aims to observe and explain the effect of sloshing on ship motions and the interaction with the research methodology systematically carried through the calculation/numerical simulations (Mathematics and Computational Fluid Dynamics Laboratory), and the physical scale model testing (at Maneuvering and Ocean Engineering Basin).The results of the study through experiments and numerical phenomenon suggests that the effect of sloshing on the effect of ship motion can be well understood. Pressure due to the wave heading angle of 90 degrees gives a higher impact pressure. Style sloshing is not directly proportional to the amplitude of excitation.Â AbstrakKajian pengaruh dari sloshing terhadap gerakan kopel heave dan picth setelah menerima gaya external berupa energi gelombang yang bervariasi dan variasi sudut heading. Kajian ini akan melakukan kajian pengujian model fisik dengan konfigurasi tambat yang dan program matematik MAT-LAB dari model matematika free floating barge mechanism serta melalui simulasi numerik computational fluid dynamic (CFD).Penelitian bertujuan mengamati dan menjelaskan pengaruh sloshing terhadap gerakan kapal dan interaksi tersebut secara sistimatis dengan metodologi penelitian yang dilakukan melalui perhitungan/ simulasi numerik (mathematics laboratory dan computational fluid dynamics), dan pengujian model skala fisik (di maneuvering and ocean engineering basin). Konfigurasi geometri model yang disimulasikan dan diuji adalah tipe FLNG dengan tangki berisi muatan cair yang memungkinkan terdapat permukaan bebas.Hasil kajian melalui eksperimen dan numerik menunjukkan bahwa efek fenomena sloshing terhadap pengaruh gerakan kapal dapat diketahui dengan baik. Pada sudut heading 900 terdapat gerakan yang tidak jelas sehingga perlu adanya investigasi lebih lanjut. Persamaan nonlinier aliran sloshing sangat diperlukan untuk dapat menghitung besaran gerakan kapal. Tekanan akibat gelombang pada sudut heading 900 memberikan dampak tekanan yang lebih tinggi. Gaya sloshing tidak berbanding lurus dengan amplitudo eksitasi. Oleh karena itu, gerakan kapal ditambah dengan sloshing tidak bervariasi secara linier terhadap amplitudo gelombang.Â

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Effect of Partially Filled Spherical Cargo Tanks on the Roll Response of a Bargelike Vessel

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.4032658 ◽

2016 ◽

Vol 138 (3) ◽

Cited By ~ 3

Author(s):

Wenhua Zhao ◽

Finlay McPhail ◽

Mike Efthymiou

Keyword(s):

Natural Gas ◽

Critical Role ◽

Response Spectra ◽

Liquefied Natural Gas ◽

Offshore Structure ◽

Operational Window ◽

Response Amplitude Operators ◽

First Time ◽

Load Conditions ◽

Game Changer

Floating liquefied natural gas (FLNG) is an offshore structure which enables liquefaction, storage, and offloading of natural gas. It is a game changer in offshore hydrocarbon development. Side-by-side offloading is a promising way of transferring liquefied natural gas (LNG) from FLNG to an LNG carrier. The roll response of LNG carriers, which plays a critical role, has been observed to be influenced by the liquid cargo motion inside the tanks. Therefore, the operational window for side-by-side offloading may not be estimated robustly using a simplified method which ignores the liquid cargo and considers only the ballast condition. This necessitates a scientific understanding of the roll responses of an LNG carrier at different load conditions. In this study, a series of model tests are conducted on a bargelike vessel with two spherical tanks. The response amplitude operators (RAOs) and response spectra of the vessel in different load conditions and different headings are investigated. The effect of intermediate cargo volumes on global roll response is, for the first time, examined for spherical cargo tanks. It is suggested that intermediate loading conditions with explicit inclusion of the effects of cargo sloshing is utilized in side-by-side operability studies to robustly ascertain offloading availability.

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