The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform

Fengmei Jing - One of the best experts on this subject based on the ideXlab platform.

  • study of the hydrodynamic derivatives of vertical axis tidal current turbines in Surge Motion
    Renewable Energy, 2016
    Co-Authors: Qihu Sheng, Fengmei Jing, Liang Zhang, Nianfu Zhou, Shuqi Wang, Zhiyang Zhang
    Abstract:

    Both the particle velocity of waves and the response of floating platforms influence hydrodynamic loads of floating tidal current turbines. In this paper, the influence of Surge Motion on vertical-axis turbines was studied; numerical simulation results were validated by experimental results. Based on numerical simulation results, a double trigonometric function was developed to fit the time history curves of hydrodynamic derivatives because of the dual frequency characteristics of vertical-axis turbines. Then least squares method was used to solve hydrodynamic derivatives of force coefficient. The results showed that in the working condition, Surge Motion results in the periodic variation of peak value of instantaneous hydrodynamic loads and that maximum loads on the turbine increased, which is bad for structural strength of the turbine. Under small Surge Motion, hydrodynamic loads on the vertical-axis turbines are linearly related to Surge Motion velocity and acceleration. Under stable conditions, damping coefficient in Surge Motion is not dependent on the amplitude, phase and frequency of Surge Motion but is related to the tip speed ratio, phase angle of the blade. The research results are beneficial to the design of mooring systems and are significant for forecasting the Motion response characteristics of floating tidal current power stations.

  • the effects of Surge Motion of the floating platform on hydrodynamics performance of horizontal axis tidal current turbine
    Renewable Energy, 2015
    Co-Authors: Liang Zhang, Qihu Sheng, Shuqi Wang, Fengmei Jing
    Abstract:

    Under practical operation conditions, hydrodynamic characteristics of floating horizontal-axis turbine are affected by the wave-induced Motion response of the floating platform for the turbine system. In this thesis, CFX software is adopted to analyze the hydrodynamic performance of the turbine in constant inflow with the turbine being forced vibrating and to study how the hydrodynamic performance of the turbine is influenced by Surge frequency, Surge amplitude and speed ratio. Based on the simulation data from CFX, axial damping coefficient can be obtained by least square fitting the time-varying axial force curves of surging turbine. The simulation results demonstrate that compared with turbine only rotating in constant inflow, shaft loads and energy utilization ratio of the surging turbine experience oscillations respectively; the oscillation amplitudes of these two parameters have a positive correlation with the frequency and amplitude of the Surge and speed ratio; the frequency and amplitude of the Surge have little impact on axial damping coefficient but this coefficient is positively proportioned to the rotational speed of the turbine. The results of this study can provide data to study Motion response of floating platform for floating tidal current turbine system and control design of the output electricity.

Qihu Sheng - One of the best experts on this subject based on the ideXlab platform.

  • study of the hydrodynamic derivatives of vertical axis tidal current turbines in Surge Motion
    Renewable Energy, 2016
    Co-Authors: Qihu Sheng, Fengmei Jing, Liang Zhang, Nianfu Zhou, Shuqi Wang, Zhiyang Zhang
    Abstract:

    Both the particle velocity of waves and the response of floating platforms influence hydrodynamic loads of floating tidal current turbines. In this paper, the influence of Surge Motion on vertical-axis turbines was studied; numerical simulation results were validated by experimental results. Based on numerical simulation results, a double trigonometric function was developed to fit the time history curves of hydrodynamic derivatives because of the dual frequency characteristics of vertical-axis turbines. Then least squares method was used to solve hydrodynamic derivatives of force coefficient. The results showed that in the working condition, Surge Motion results in the periodic variation of peak value of instantaneous hydrodynamic loads and that maximum loads on the turbine increased, which is bad for structural strength of the turbine. Under small Surge Motion, hydrodynamic loads on the vertical-axis turbines are linearly related to Surge Motion velocity and acceleration. Under stable conditions, damping coefficient in Surge Motion is not dependent on the amplitude, phase and frequency of Surge Motion but is related to the tip speed ratio, phase angle of the blade. The research results are beneficial to the design of mooring systems and are significant for forecasting the Motion response characteristics of floating tidal current power stations.

  • the effects of Surge Motion of the floating platform on hydrodynamics performance of horizontal axis tidal current turbine
    Renewable Energy, 2015
    Co-Authors: Liang Zhang, Qihu Sheng, Shuqi Wang, Fengmei Jing
    Abstract:

    Under practical operation conditions, hydrodynamic characteristics of floating horizontal-axis turbine are affected by the wave-induced Motion response of the floating platform for the turbine system. In this thesis, CFX software is adopted to analyze the hydrodynamic performance of the turbine in constant inflow with the turbine being forced vibrating and to study how the hydrodynamic performance of the turbine is influenced by Surge frequency, Surge amplitude and speed ratio. Based on the simulation data from CFX, axial damping coefficient can be obtained by least square fitting the time-varying axial force curves of surging turbine. The simulation results demonstrate that compared with turbine only rotating in constant inflow, shaft loads and energy utilization ratio of the surging turbine experience oscillations respectively; the oscillation amplitudes of these two parameters have a positive correlation with the frequency and amplitude of the Surge and speed ratio; the frequency and amplitude of the Surge have little impact on axial damping coefficient but this coefficient is positively proportioned to the rotational speed of the turbine. The results of this study can provide data to study Motion response of floating platform for floating tidal current turbine system and control design of the output electricity.

Liang Zhang - One of the best experts on this subject based on the ideXlab platform.

  • study of the hydrodynamic derivatives of vertical axis tidal current turbines in Surge Motion
    Renewable Energy, 2016
    Co-Authors: Qihu Sheng, Fengmei Jing, Liang Zhang, Nianfu Zhou, Shuqi Wang, Zhiyang Zhang
    Abstract:

    Both the particle velocity of waves and the response of floating platforms influence hydrodynamic loads of floating tidal current turbines. In this paper, the influence of Surge Motion on vertical-axis turbines was studied; numerical simulation results were validated by experimental results. Based on numerical simulation results, a double trigonometric function was developed to fit the time history curves of hydrodynamic derivatives because of the dual frequency characteristics of vertical-axis turbines. Then least squares method was used to solve hydrodynamic derivatives of force coefficient. The results showed that in the working condition, Surge Motion results in the periodic variation of peak value of instantaneous hydrodynamic loads and that maximum loads on the turbine increased, which is bad for structural strength of the turbine. Under small Surge Motion, hydrodynamic loads on the vertical-axis turbines are linearly related to Surge Motion velocity and acceleration. Under stable conditions, damping coefficient in Surge Motion is not dependent on the amplitude, phase and frequency of Surge Motion but is related to the tip speed ratio, phase angle of the blade. The research results are beneficial to the design of mooring systems and are significant for forecasting the Motion response characteristics of floating tidal current power stations.

  • the effects of Surge Motion of the floating platform on hydrodynamics performance of horizontal axis tidal current turbine
    Renewable Energy, 2015
    Co-Authors: Liang Zhang, Qihu Sheng, Shuqi Wang, Fengmei Jing
    Abstract:

    Under practical operation conditions, hydrodynamic characteristics of floating horizontal-axis turbine are affected by the wave-induced Motion response of the floating platform for the turbine system. In this thesis, CFX software is adopted to analyze the hydrodynamic performance of the turbine in constant inflow with the turbine being forced vibrating and to study how the hydrodynamic performance of the turbine is influenced by Surge frequency, Surge amplitude and speed ratio. Based on the simulation data from CFX, axial damping coefficient can be obtained by least square fitting the time-varying axial force curves of surging turbine. The simulation results demonstrate that compared with turbine only rotating in constant inflow, shaft loads and energy utilization ratio of the surging turbine experience oscillations respectively; the oscillation amplitudes of these two parameters have a positive correlation with the frequency and amplitude of the Surge and speed ratio; the frequency and amplitude of the Surge have little impact on axial damping coefficient but this coefficient is positively proportioned to the rotational speed of the turbine. The results of this study can provide data to study Motion response of floating platform for floating tidal current turbine system and control design of the output electricity.

Christophe Peyrard - One of the best experts on this subject based on the ideXlab platform.

  • aeroelastic analysis of a floating offshore wind turbine in platform induced Surge Motion using a fully coupled cfd mbd method
    Wind Energy, 2019
    Co-Authors: Qing Xiao, Atilla Incecik, Christophe Peyrard
    Abstract:

    Modern offshore wind turbines are susceptible to blade deformation because of their increased size and the recent trend of installing these turbines on floating platforms in deep sea. In this paper, an aeroelastic analysis tool for floating offshore wind turbines is presented by coupling a high‐fidelity computational fluid dynamics (CFD) solver with a general purpose multibody dynamics code, which is capable of modelling flexible bodies based on the nonlinear beam theory. With the tool developed, we demonstrated its applications to the NREL 5 MW offshore wind turbine with aeroelastic blades. The impacts of blade flexibility and platform‐induced Surge Motion on wind turbine aerodynamics and structural responses are studied and illustrated by the CFD results of the flow field, force, and wake structure. Results are compared with data obtained from the engineering tool FAST v8.

  • Aeroelastic analysis of a floating offshore wind turbine in platform‐induced Surge Motion using a fully coupled CFD‐MBD method
    Wind Energy, 2018
    Co-Authors: Qing Xiao, Atilla Incecik, Christophe Peyrard
    Abstract:

    Modern offshore wind turbines are susceptible to blade deformation because of their increased size and the recent trend of installing these turbines on floating platforms in deep sea. In this paper, an aeroelastic analysis tool for floating offshore wind turbines is presented by coupling a high‐fidelity computational fluid dynamics (CFD) solver with a general purpose multibody dynamics code, which is capable of modelling flexible bodies based on the nonlinear beam theory. With the tool developed, we demonstrated its applications to the NREL 5 MW offshore wind turbine with aeroelastic blades. The impacts of blade flexibility and platform‐induced Surge Motion on wind turbine aerodynamics and structural responses are studied and illustrated by the CFD results of the flow field, force, and wake structure. Results are compared with data obtained from the engineering tool FAST v8.

Zhiyang Zhang - One of the best experts on this subject based on the ideXlab platform.

  • study of the hydrodynamic derivatives of vertical axis tidal current turbines in Surge Motion
    Renewable Energy, 2016
    Co-Authors: Qihu Sheng, Fengmei Jing, Liang Zhang, Nianfu Zhou, Shuqi Wang, Zhiyang Zhang
    Abstract:

    Both the particle velocity of waves and the response of floating platforms influence hydrodynamic loads of floating tidal current turbines. In this paper, the influence of Surge Motion on vertical-axis turbines was studied; numerical simulation results were validated by experimental results. Based on numerical simulation results, a double trigonometric function was developed to fit the time history curves of hydrodynamic derivatives because of the dual frequency characteristics of vertical-axis turbines. Then least squares method was used to solve hydrodynamic derivatives of force coefficient. The results showed that in the working condition, Surge Motion results in the periodic variation of peak value of instantaneous hydrodynamic loads and that maximum loads on the turbine increased, which is bad for structural strength of the turbine. Under small Surge Motion, hydrodynamic loads on the vertical-axis turbines are linearly related to Surge Motion velocity and acceleration. Under stable conditions, damping coefficient in Surge Motion is not dependent on the amplitude, phase and frequency of Surge Motion but is related to the tip speed ratio, phase angle of the blade. The research results are beneficial to the design of mooring systems and are significant for forecasting the Motion response characteristics of floating tidal current power stations.