The Experts below are selected from a list of 35223 Experts worldwide ranked by ideXlab platform
Chao Wang - One of the best experts on this subject based on the ideXlab platform.
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numerical prediction analysis of propeller exciting force for hull propeller rudder system in oblique flow
International Journal of Naval Architecture and Ocean Engineering, 2018Co-Authors: Shuai Sun, Chao Wang, Hongyu ZhangAbstract:Abstract In order to analyze the characteristics of propeller exciting force, the Hybrid Grid is adopted and the numerical prediction of KCS ship model is performed for hull–propeller–rudder system by Reynolds-Averaged Navier Stokes (RANS) method and volume of fluid (VOF) model. Firstly, the numerical simulation of hydrodynamics for bare hull at oblique state is carried out. The results show that with the increasing of the drift angle, the coefficients of resistance, side force and yaw moment are constantly increasing, and the bigger the drift angle, the worse the overall uniformity of propeller disk. Then, propeller bearing force for hull–propeller–rudder system in oblique flow is calculated. It is found that the propeller thrust and torque fluctuation coefficient peak in drift angle are greater than that in straight line navigation, and the negative drift angle is greater than the positive. The fluctuation peak variation law of coefficient of side force and bending moment are different due to various causes.
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Numerical prediction analysis of propeller exciting force for hull–propeller–rudder system in oblique flow
International Journal of Naval Architecture and Ocean Engineering, 2017Co-Authors: Shuai Sun, Chao Wang, Hongyu ZhangAbstract:Abstract In order to analyze the characteristics of propeller exciting force, the Hybrid Grid is adopted and the numerical prediction of KCS ship model is performed for hull–propeller–rudder system by Reynolds-Averaged Navier Stokes (RANS) method and volume of fluid (VOF) model. Firstly, the numerical simulation of hydrodynamics for bare hull at oblique state is carried out. The results show that with the increasing of the drift angle, the coefficients of resistance, side force and yaw moment are constantly increasing, and the bigger the drift angle, the worse the overall uniformity of propeller disk. Then, propeller bearing force for hull–propeller–rudder system in oblique flow is calculated. It is found that the propeller thrust and torque fluctuation coefficient peak in drift angle are greater than that in straight line navigation, and the negative drift angle is greater than the positive. The fluctuation peak variation law of coefficient of side force and bending moment are different due to various causes.
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numerical prediction analysis of propeller bearing force for full scale hull propeller rudder system
International Journal of Naval Architecture and Ocean Engineering, 2016Co-Authors: Chao Wang, Liang Li, Liyu YeAbstract:Abstract The Hybrid Grid was adopted and numerical prediction analysis of propeller unsteady bearing force considering free surface was performed for mode and full-scale KCS hull–propeller–rudder system by employing RANS method and VOF model. In order to obtain the propeller velocity under self-propulsion point, firstly, the numerical simulation for self-propulsion test of full-scale ship is carried out. The results show that the scale effect of velocity at self-propulsion point and wake fraction is obvious. Then, the transient two-phase flow calculations are performed for model and full-scale KCS hull–propeller–rudder systems. According to the monitoring data, it is found that the propeller unsteady bearing force is fluctuating periodically over time and full-scale propeller's time-average value is smaller than model-scale's. The frequency spectrum curves are also provided after fast Fourier transform. By analyzing the frequency spectrum data, it is easy to summarize that each component of the propeller bearing force have the same fluctuation frequency and the peak in BFP is maximum. What's more, each component of full-scale bearing force's fluctuation value is bigger than model-scale's except the bending moment coefficient about the Y-axis.
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Numerical prediction analysis of propeller bearing force for full-scale hull–propeller–rudder system
International Journal of Naval Architecture and Ocean Engineering, 2016Co-Authors: Chao Wang, Liang Li, Liyu YeAbstract:Abstract The Hybrid Grid was adopted and numerical prediction analysis of propeller unsteady bearing force considering free surface was performed for mode and full-scale KCS hull–propeller–rudder system by employing RANS method and VOF model. In order to obtain the propeller velocity under self-propulsion point, firstly, the numerical simulation for self-propulsion test of full-scale ship is carried out. The results show that the scale effect of velocity at self-propulsion point and wake fraction is obvious. Then, the transient two-phase flow calculations are performed for model and full-scale KCS hull–propeller–rudder systems. According to the monitoring data, it is found that the propeller unsteady bearing force is fluctuating periodically over time and full-scale propeller's time-average value is smaller than model-scale's. The frequency spectrum curves are also provided after fast Fourier transform. By analyzing the frequency spectrum data, it is easy to summarize that each component of the propeller bearing force have the same fluctuation frequency and the peak in BFP is maximum. What's more, each component of full-scale bearing force's fluctuation value is bigger than model-scale's except the bending moment coefficient about the Y-axis.
Liyu Ye - One of the best experts on this subject based on the ideXlab platform.
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numerical prediction analysis of propeller bearing force for full scale hull propeller rudder system
International Journal of Naval Architecture and Ocean Engineering, 2016Co-Authors: Chao Wang, Liang Li, Liyu YeAbstract:Abstract The Hybrid Grid was adopted and numerical prediction analysis of propeller unsteady bearing force considering free surface was performed for mode and full-scale KCS hull–propeller–rudder system by employing RANS method and VOF model. In order to obtain the propeller velocity under self-propulsion point, firstly, the numerical simulation for self-propulsion test of full-scale ship is carried out. The results show that the scale effect of velocity at self-propulsion point and wake fraction is obvious. Then, the transient two-phase flow calculations are performed for model and full-scale KCS hull–propeller–rudder systems. According to the monitoring data, it is found that the propeller unsteady bearing force is fluctuating periodically over time and full-scale propeller's time-average value is smaller than model-scale's. The frequency spectrum curves are also provided after fast Fourier transform. By analyzing the frequency spectrum data, it is easy to summarize that each component of the propeller bearing force have the same fluctuation frequency and the peak in BFP is maximum. What's more, each component of full-scale bearing force's fluctuation value is bigger than model-scale's except the bending moment coefficient about the Y-axis.
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Numerical prediction analysis of propeller bearing force for full-scale hull–propeller–rudder system
International Journal of Naval Architecture and Ocean Engineering, 2016Co-Authors: Chao Wang, Liang Li, Liyu YeAbstract:Abstract The Hybrid Grid was adopted and numerical prediction analysis of propeller unsteady bearing force considering free surface was performed for mode and full-scale KCS hull–propeller–rudder system by employing RANS method and VOF model. In order to obtain the propeller velocity under self-propulsion point, firstly, the numerical simulation for self-propulsion test of full-scale ship is carried out. The results show that the scale effect of velocity at self-propulsion point and wake fraction is obvious. Then, the transient two-phase flow calculations are performed for model and full-scale KCS hull–propeller–rudder systems. According to the monitoring data, it is found that the propeller unsteady bearing force is fluctuating periodically over time and full-scale propeller's time-average value is smaller than model-scale's. The frequency spectrum curves are also provided after fast Fourier transform. By analyzing the frequency spectrum data, it is easy to summarize that each component of the propeller bearing force have the same fluctuation frequency and the peak in BFP is maximum. What's more, each component of full-scale bearing force's fluctuation value is bigger than model-scale's except the bending moment coefficient about the Y-axis.
Manchung Wong - One of the best experts on this subject based on the ideXlab platform.
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comparisons of different Hybrid inverters for power quality compensation with without active power injection
Conference of the Industrial Electronics Society, 2018Co-Authors: Lei Wang, Chiseng Lam, Manchung WongAbstract:In this paper, the comparisons of different Hybrid inverters are provided for power quality compensation and/or active inverter injection. In detail, the characteristics are compared for inductive coupling Grid connected inverter (IGCI), capacitive coupling Grid connected inverter (CGCI), static var compensator (SVC) in parallel with a CGCI (SVC//CGCI), and Hybrid Grid connected inverter (HGCI). The comparisons are separately provided for two applications: 1) power quality compensation 2) both power quality compensation and active power injection. In this paper, the circuit configurations of different inverters are proposed firstly. Then, the design of each Hybrid inverters is provided. After that, the comparisons are provided for above mentioned applications. Finally, the simulation results are provided to verify the characteristics of different Hybrid inverters.
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analysis control and design of a Hybrid Grid connected inverter for renewable energy generation with power quality conditioning
IEEE Transactions on Power Electronics, 2018Co-Authors: Lei Wang, Manchung WongAbstract:This paper proposes a new type dc/ac inverter named: Hybrid-coupling Grid-connected inverter (HGCI) for photovoltaic active power generation with power quality conditioning, which consists of a full-bridge three-phase dc/ac inverter coupling to the power Grid in series with a thyristor-controlled LC filter. Compared with the conventional inductive-coupling Grid-connected inverter (IGCI) and capacitive-coupling Grid-connected inverter (CGCI), the proposed HGCI has distinct characteristics of wide operational range and low dc-link operating voltage. Based on these prominent characteristics, the system cost and operational cost can be reduced. Moreover, it can transfer the active power and compensate reactive power, unbalanced power, and harmonic power simultaneously. In this paper, the analysis of the structure, parameter design, and control method of the HGCI is proposed and presented. Finally, simulation and experimental results are provided to verify the effectiveness and performance of the proposed HGCI in comparison with the IGCI and CGCI.
Hongyu Zhang - One of the best experts on this subject based on the ideXlab platform.
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numerical prediction analysis of propeller exciting force for hull propeller rudder system in oblique flow
International Journal of Naval Architecture and Ocean Engineering, 2018Co-Authors: Shuai Sun, Chao Wang, Hongyu ZhangAbstract:Abstract In order to analyze the characteristics of propeller exciting force, the Hybrid Grid is adopted and the numerical prediction of KCS ship model is performed for hull–propeller–rudder system by Reynolds-Averaged Navier Stokes (RANS) method and volume of fluid (VOF) model. Firstly, the numerical simulation of hydrodynamics for bare hull at oblique state is carried out. The results show that with the increasing of the drift angle, the coefficients of resistance, side force and yaw moment are constantly increasing, and the bigger the drift angle, the worse the overall uniformity of propeller disk. Then, propeller bearing force for hull–propeller–rudder system in oblique flow is calculated. It is found that the propeller thrust and torque fluctuation coefficient peak in drift angle are greater than that in straight line navigation, and the negative drift angle is greater than the positive. The fluctuation peak variation law of coefficient of side force and bending moment are different due to various causes.
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Numerical prediction analysis of propeller exciting force for hull–propeller–rudder system in oblique flow
International Journal of Naval Architecture and Ocean Engineering, 2017Co-Authors: Shuai Sun, Chao Wang, Hongyu ZhangAbstract:Abstract In order to analyze the characteristics of propeller exciting force, the Hybrid Grid is adopted and the numerical prediction of KCS ship model is performed for hull–propeller–rudder system by Reynolds-Averaged Navier Stokes (RANS) method and volume of fluid (VOF) model. Firstly, the numerical simulation of hydrodynamics for bare hull at oblique state is carried out. The results show that with the increasing of the drift angle, the coefficients of resistance, side force and yaw moment are constantly increasing, and the bigger the drift angle, the worse the overall uniformity of propeller disk. Then, propeller bearing force for hull–propeller–rudder system in oblique flow is calculated. It is found that the propeller thrust and torque fluctuation coefficient peak in drift angle are greater than that in straight line navigation, and the negative drift angle is greater than the positive. The fluctuation peak variation law of coefficient of side force and bending moment are different due to various causes.
Olatz Terreros - One of the best experts on this subject based on the ideXlab platform.
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case studies of energy Grid Hybridization in a northern european city
IEEE Transactions on Sustainable Energy, 2019Co-Authors: Tobias Jacobs, Sebastien Nicolas, Taegil Noh, Anett Schuelke, Hans Auer, Daniel Schwabeneder, Edmund Widl, Daniele Basciotti, Sawsan Henein, Olatz TerrerosAbstract:We present two case studies on energy Grid Hybridization , where the distribution networks of multiple energy sectors are more tightly coupled together to increase their flexibility via mutual transfer of energy. The Hybridization approaches were developed in cooperation with the local stakeholder in a northern European city, comprising of a short-term setup with a low adoption barrier as well as a long-term scenario with more involved Grid coupling using more efficient devices. For a range of coupling device configurations, device locations, control algorithms, and assumptions on utility prices and energy demand, we investigate the influence of the Hybridization on the energy mix, $\text{CO}_2$ emissions, and energy costs. The studies have been conducted using a co-simulation toolchain developed by the European Project OrPHEuS specifically for fine-grained technical simulation of multi-carrier Grids. Our results confirm that the Hybrid Grid approach is an effective means to increase the share of renewable energies and reduce operational costs. It also turns out that precise forecasts of energy demand and utility prices are essential for appropriate dimensioning of the coupling points.
