Dongyue Tang¹, Ming Zhao^{1, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.2, pp. 433-457, 2020, DOI:10.32604/cmes.2020.09268

Abstract The monopile foundation is the main form of offshore wind turbine foundation, and its surrounding scouring pit will reduce the constraints of the soil on the piles, which makes wind turbine foundation instability a key issue affecting the structural safety of offshore wind turbines. In previous studies, the rotating rotor and control system are neglected when studying the influence of scour on the offshore wind turbine structure. In this paper, the numerical model of the blade-tower-monopile integrated offshore wind turbine is established, and the influence of scour on the dynamic characteristics of wind turbine is obtained considering parameters, such as… More >

Y. S. Hamed^{1, 2, *}, Ayman A. Al^{3, 4}, B. Sale^{3, 4}, Ageel F. Alogla³, Awad M. Aljuaid³, Mosleh M. Alharthi0F⁵

CMC-Computers, Materials & Continua, Vol.64, No.2, pp. 871-886, 2020, DOI:10.32604/cmc.2020.08120

Abstract In this paper, we studied the vibration performance, energy transfer and stability of the offshore wind turbine tower system under mixed excitations. The method of multiple scales is utilized to calculate the approximate solutions of wind turbine system. The proportional-derivative controller was applied for reducing the oscillations of the controlled system. Adding the controller to single degree of freedom system equation is responsible for energy transfers in offshore wind turbine tower system. The steady state solution of stability at worst resonance cases is studied and examined. The offshore wind turbine system behavior was studied numerically at its different parameters values.… More >

Hongyi Yan¹, Dingguo Zhang¹, Liang Li^1,*, Xiaoyu Luo²

Structural Durability & Health Monitoring, Vol.14, No.1, pp. 19-36, 2020, DOI:10.32604/sdhm.2020.07457

Abstract The construction of seaside facilities is a hot topic in the field of ocean engineering. In this paper, a new type of floating breakwater is designed by 3DCAD geometric modeling. Based on the vibration theory and finite element technology, the floating breakwater model is optimized, and the modal analysis of the structure with the bracket as main body and blades as functional attachments is carried out. Natural frequencies and mode shapes of the blades are first calculated, and the effects of the natural frequencies in both dry and wet conditions are taken into account. Modal analysis and harmonic response analysis… More >

Haytham Ayoub, Ehab Hussein Bani-Hani^*

Energy Engineering, Vol.117, No.1, pp. 41-47, 2020, DOI:10.32604/EE.2020.010412

Abstract Offshore wind turbine is analyzed theoretically and experimentally for improving wind energy harvesting. The energy produced is calculated at different wind speeds. The wind speed curve is generated by measuring the wind speed on daily base for one year. Curves that show the power extraction for experimental study and from the theoretical calculations are generated. The energy production investigation is expanded over a period of 15 years after comparing the annual energy production in theory and practice. The study shows the cost of electricity over the same time period assuming different interest rates. Three time intervals are shown that are… More >

Jeong Hwan Kim, Du Chan Kim, Ju Hye Park, Bong Ju Kim, Jung Kwan Seo, Jeom Kee Paik, Satya N. Atluri

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.2, pp. 63-64, 2011, DOI:10.3970/icces.2011.019.063

Abstract In offshore structures, fire is one of the most important hazardous events. This has been proved by several disasters such as Piper Alpha and Deepwater Horizon accidents. The concern of fires has recently been reflected in rules and quantified risk assessment based design practice. Within the framework of quantified risk assessment and management for offshore installations, therefore, more refined computations of consequences or hazardous action effects due to fire is required.
The aim of the present study is to examine the technologies involved in computations of nonlinear structural analysis of offshore structures subject to temperature due to fire. It… More >

Yong Chen^1,*, Weihua Lan¹, Chong Wang²

Journal on Big Data, Vol.1, No.2, pp. 47-54, 2019, DOI:10.32604/jbd.2019.06282

Abstract In order to solve information island problem of offshore oil and gas field production-related information system, including repetitive reporting and input of data, data isolation of central control system, inadequate follow-up analysis and development to support oil and gas field production management, and so on. Therefore, the introduction of MES (Manufacturing Execution System) production execution system in the manufacturing industry and downstream production of offshore oil has become an inevitable choice. This system utilizes the real-time database combined with relational database to collect the scattered structured data, such as the production process real-time data, production management documents and statistical tables… More >

Yong Chen^1,*, Lei Cui¹, Chong Wang²

Journal of Quantum Computing, Vol.1, No.1, pp. 41-48, 2019, DOI:10.32604/jqc.2019.06283

Abstract In order to solve the problem of data island in the safety management of offshore oil and gas fields, take full advantage of data for subsequent analysis and development, and support production safety management of oil and gas fields, the MES, which is maturely applied in manufacturing and downstream production of CNOOC (China National Offshore Oil Corporation), is introduced by the petroleum administration at the eastern South China sea. The system adopts the real-time database and relational database to collect the scattered structured data, such as evidence information of offshore oil and gas production facilities personnel, on-site hidden danger information… More >

Tianyu Wu¹, Wenliang Qiu^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.115, No.1, pp. 47-66, 2018, DOI:10.3970/cmes.2018.115.047

Abstract The action of drifting ice floes may induce strong vibrations of offshore structures, and further reduce the structural safety and serviceability. The aim of this paper is to develop a method by considering ice crushing as a stochastic process. On the basis of ice force spectrum which considers the time and spatial correlation between the local ice forces, a simulation methodology to generate the stochastic ice forces process of vertical offshore structure is proposed. The crucial segment in the simulation is to accurately calculate the effective ice pressure, and it is accomplished by an empirical formula which can provide a… More >

Cui Li¹, Deli Gao¹, Zhiyong Wu¹, Binbin Diao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.89, No.1, pp. 39-56, 2012, DOI:10.3970/cmes.2012.089.039

Abstract At present, a relief well is the most reliable method to control serious blowout accidents, and it is necessary to detect very accurately the relative position of the relief well and the blowout well. The detection tool should be capable of detecting directly the relative distance and direction between the relief well and the blowout well. Its detection accuracy should also meet the engineering demand of drilling a relief well. Using the working principle of a proposed detection tool, this paper analyzes the spread and attenuation laws of the current injected by a single-electrode or three-electrode array in the relief… More >

Yanbin Wang^1,2, Deli Gao¹, Jun Fang¹

CMC-Computers, Materials & Continua, Vol.48, No.1, pp. 25-42, 2015, DOI:10.3970/cmc.2015.048.025

Abstract In this paper, the buckling and collapse analysis of offshore pipeline under combined tension, bending moment, and external pressure has been presented with theoretical analysis and FE (finite element) simulation method respectively. Based on the model initially proposed by Kyriakides, a 2-D theoretical model has been further developed. To verify the correctness and accuracy of the model proposed in this paper, numerical simulations have been conducted with 3-D FE model using ABAQUS software. Good consistency has been shown between the calculation results which validate the availability of the theoretical analysis. On this basis, the influence of load path, material properties,… More >