The Experts below are selected from a list of 186 Experts worldwide ranked by ideXlab platform
Madhusuden Agrawal - One of the best experts on this subject based on the ideXlab platform.
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coupled transient cfd and diffraction modeling for installation of Subsea equipment structures in splash zone
ASME 2013 32nd International Conference on Ocean Offshore and Arctic Engineering, 2013Co-Authors: Madhusuden AgrawalAbstract:In development of deep water oil and gas fields, successfully and economically installing Subsea equipment and structure is critically important. This paper presents a state-of-the-art methodology for predicting the motions and loads of Subsea equipment/structure during such operations basing on time domain simulations of the combined installation vessel and Subsea equipment/structure. The time domain diffraction simulation of the moving lifting vessel is coupled with multiphase CFD simulation of Subsea equipment/structure in splash zone. Transient CFD model with rigid body motion for the equipment/structure calculates added masses, forces and moments on the equipment/structure for diffraction analysis, while diffraction analysis calculates linear and angular velocities for CFD simulation. This paper has many potential applications, such as, installation of pile, manifold, Subsea Tree, PLET/PLEM, or other Subsea equipment/structure. This coupled approach has been successfully implemented on a cylindrical structure. The results show that total load level, and dynamics of the Subsea equipment/structure due to waves in splash zone are predicted. Current practice of installation analysis in accordance with the recommendations from DNV-RP-H103 [1] cannot determine in detail the wave loads either during the passage through splash zone, or added mass and damping when the equipment/structure is submerged. In order to determine wave loads in detail, model tests are needed. In the absence of tests, simplified equations or empirical formulations have to be used to calculate/estimate these hydrodynamics coefficients as recommended in DNV-RP-H103. Steady-state CFD simulations on a stationary equipment/structure are usually used to predict drag and added masses on submerged structures. However the steady-state assumption in CFD ignores the resonating motion of equipment/structure in calculating hydrodynamics coefficients, which can severely affect the accuracy of these predictions. The above methods often give overly conservative results for allowable sea state which results in uneconomical vessel time or inaccurate results for installation. The methodology of this paper gives more accurate results, and provides potentially economical vessel time during installation. The intent of this paper is to demonstrate the solution and methodology.Copyright © 2013 by ASME
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Coupled Transient CFD and Diffraction Modeling for Installation of Subsea Equipment/Structures in Splash Zone
Volume 7: CFD and VIV, 2013Co-Authors: Madhusuden AgrawalAbstract:In development of deep water oil and gas fields, successfully and economically installing Subsea equipment and structure is critically important. This paper presents a state-of-the-art methodology for predicting the motions and loads of Subsea equipment/structure during such operations basing on time domain simulations of the combined installation vessel and Subsea equipment/structure. The time domain diffraction simulation of the moving lifting vessel is coupled with multiphase CFD simulation of Subsea equipment/structure in splash zone. Transient CFD model with rigid body motion for the equipment/structure calculates added masses, forces and moments on the equipment/structure for diffraction analysis, while diffraction analysis calculates linear and angular velocities for CFD simulation. This paper has many potential applications, such as, installation of pile, manifold, Subsea Tree, PLET/PLEM, or other Subsea equipment/structure. This coupled approach has been successfully implemented on a cylindrical structure. The results show that total load level, and dynamics of the Subsea equipment/structure due to waves in splash zone are predicted. Current practice of installation analysis in accordance with the recommendations from DNV-RP-H103 [1] cannot determine in detail the wave loads either during the passage through splash zone, or added mass and damping when the equipment/structure is submerged. In order to determine wave loads in detail, model tests are needed. In the absence of tests, simplified equations or empirical formulations have to be used to calculate/estimate these hydrodynamics coefficients as recommended in DNV-RP-H103. Steady-state CFD simulations on a stationary equipment/structure are usually used to predict drag and added masses on submerged structures. However the steady-state assumption in CFD ignores the resonating motion of equipment/structure in calculating hydrodynamics coefficients, which can severely affect the accuracy of these predictions. The above methods often give overly conservative results for allowable sea state which results in uneconomical vessel time or inaccurate results for installation. The methodology of this paper gives more accurate results, and provides potentially economical vessel time during installation. The intent of this paper is to demonstrate the solution and methodology.Copyright © 2013 by ASME
Deguo Wang - One of the best experts on this subject based on the ideXlab platform.
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study of the installation process of the Subsea Tree passed through the splash zone
Energies, 2020Co-Authors: Yufang Li, Xiaoyu Wang, Honglin Zhao, Ning Xu, Deguo WangAbstract:The Subsea Tree is one of the critical pieces of equipment in the Subsea production system, and its installation is related to the safe production of offshore oil and gas. Due to the differences in the form of the structures, the speed of entering the water, the marine environment, and other factors, the process of the structure entering the water is exceedingly complicated. During the engineering installation, the most dangerous phase involves the structure passing through the splash zone. Based on the theory of the movement of the Subsea Tree passing through the splash zone, Lingshui 17-2 Subsea Tree installation was analyzed with the marine engineering software OrcaFlex, and a sensitivity analysis of the lowering of the Subsea Tree was performed. During the splash zone phase, the wave height had the highest impact on the Subsea Tree, affecting the horizontal offset and cable load, which may lead to the oil Tree capsizing and cable breakage. Furthermore, the velocity only affected the horizontal offset, and the overall effect was not noticeable. The operational safety window for the Subsea Tree installation was established according to the operational safety standards. Therefore, the recommended lowering speed was 0.50 m/s, while the flow velocity should not exceed 1.50 m/s, and the wave height should not be higher than 4.5 m.
Yufang Li - One of the best experts on this subject based on the ideXlab platform.
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study of the installation process of the Subsea Tree passed through the splash zone
Energies, 2020Co-Authors: Yufang Li, Xiaoyu Wang, Honglin Zhao, Ning Xu, Deguo WangAbstract:The Subsea Tree is one of the critical pieces of equipment in the Subsea production system, and its installation is related to the safe production of offshore oil and gas. Due to the differences in the form of the structures, the speed of entering the water, the marine environment, and other factors, the process of the structure entering the water is exceedingly complicated. During the engineering installation, the most dangerous phase involves the structure passing through the splash zone. Based on the theory of the movement of the Subsea Tree passing through the splash zone, Lingshui 17-2 Subsea Tree installation was analyzed with the marine engineering software OrcaFlex, and a sensitivity analysis of the lowering of the Subsea Tree was performed. During the splash zone phase, the wave height had the highest impact on the Subsea Tree, affecting the horizontal offset and cable load, which may lead to the oil Tree capsizing and cable breakage. Furthermore, the velocity only affected the horizontal offset, and the overall effect was not noticeable. The operational safety window for the Subsea Tree installation was established according to the operational safety standards. Therefore, the recommended lowering speed was 0.50 m/s, while the flow velocity should not exceed 1.50 m/s, and the wave height should not be higher than 4.5 m.
Xiaoyu Wang - One of the best experts on this subject based on the ideXlab platform.
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study of the installation process of the Subsea Tree passed through the splash zone
Energies, 2020Co-Authors: Yufang Li, Xiaoyu Wang, Honglin Zhao, Ning Xu, Deguo WangAbstract:The Subsea Tree is one of the critical pieces of equipment in the Subsea production system, and its installation is related to the safe production of offshore oil and gas. Due to the differences in the form of the structures, the speed of entering the water, the marine environment, and other factors, the process of the structure entering the water is exceedingly complicated. During the engineering installation, the most dangerous phase involves the structure passing through the splash zone. Based on the theory of the movement of the Subsea Tree passing through the splash zone, Lingshui 17-2 Subsea Tree installation was analyzed with the marine engineering software OrcaFlex, and a sensitivity analysis of the lowering of the Subsea Tree was performed. During the splash zone phase, the wave height had the highest impact on the Subsea Tree, affecting the horizontal offset and cable load, which may lead to the oil Tree capsizing and cable breakage. Furthermore, the velocity only affected the horizontal offset, and the overall effect was not noticeable. The operational safety window for the Subsea Tree installation was established according to the operational safety standards. Therefore, the recommended lowering speed was 0.50 m/s, while the flow velocity should not exceed 1.50 m/s, and the wave height should not be higher than 4.5 m.
Ning Xu - One of the best experts on this subject based on the ideXlab platform.
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study of the installation process of the Subsea Tree passed through the splash zone
Energies, 2020Co-Authors: Yufang Li, Xiaoyu Wang, Honglin Zhao, Ning Xu, Deguo WangAbstract:The Subsea Tree is one of the critical pieces of equipment in the Subsea production system, and its installation is related to the safe production of offshore oil and gas. Due to the differences in the form of the structures, the speed of entering the water, the marine environment, and other factors, the process of the structure entering the water is exceedingly complicated. During the engineering installation, the most dangerous phase involves the structure passing through the splash zone. Based on the theory of the movement of the Subsea Tree passing through the splash zone, Lingshui 17-2 Subsea Tree installation was analyzed with the marine engineering software OrcaFlex, and a sensitivity analysis of the lowering of the Subsea Tree was performed. During the splash zone phase, the wave height had the highest impact on the Subsea Tree, affecting the horizontal offset and cable load, which may lead to the oil Tree capsizing and cable breakage. Furthermore, the velocity only affected the horizontal offset, and the overall effect was not noticeable. The operational safety window for the Subsea Tree installation was established according to the operational safety standards. Therefore, the recommended lowering speed was 0.50 m/s, while the flow velocity should not exceed 1.50 m/s, and the wave height should not be higher than 4.5 m.
