Horizontal axis tidal turbines have attracted more and more attentions nowadays, because of their convenience and low expense in construction and high efficiency in extracting tidal energy. The present study numerical...Horizontal axis tidal turbines have attracted more and more attentions nowadays, because of their convenience and low expense in construction and high efficiency in extracting tidal energy. The present study numerically investigates the flow motion and performance of a horizontal axis tidal turbine with a supporting vertical cylinder under steady current. In the numerical model, the continuous equation and incompressible Reynolds-averaged Navier-Stokes equations are solved, and the volume of fluid method is employed to track free surface motion. The RNG k-ε model is adopted to calculate turbulence transport while the fractional area/volume obstacle representation method is used to describe turbine characteristics and movement. The effects of installation elevation of tidal turbine and inlet velocity on the water elevation, and current velocity, rotating speed and resultant force on turbine are discussed. Based on the comparison of the numerical results, a better understanding of flow structure around horizontal axis tidal turbine and turbine performance is achieved.展开更多
Essential Variables are defined as a minimal set of variables that explain the state of the system.They are crucial for predicting its developments,and support metrics that measure its evolution.The variables should b...Essential Variables are defined as a minimal set of variables that explain the state of the system.They are crucial for predicting its developments,and support metrics that measure its evolution.The variables should be relevant to meet requirements of stakeholders and be technically and economically feasible for systematic observation.A definition of Essential Renewable Energies Variables is proposed linked with their identification in several domains in renewable energy using a bottom-up and userdriven approach,and spanning over several years of documented interaction with stakeholders.Lists of variables are proposed in hydropower,solar,wind,and marine energies.It does not comprise the variables relating to social and economic aspects supporting decision making in investment nor those relating to civil engineering that are needed to erect a plant or farm.展开更多
基金funded by by the National Science Fund for Distinguished Young Scholars(Grant No.51425901)the National Natural Science Foundation of China(Grant Nos.51479053 and 51137002)+4 种基金the Natural Science Foundation of Jiangsu Province(Grant No.BK2011026)the 111 Project(Grant No.B2012032)the Specialized Research Funding for the Doctoral Program of Higher Education(Grant No.20130094110014)the Marine Renewable Energy Research Project of State Oceanic Administration(Grant No.GHME2013GC03)the Fundamental Research Funds for the Central University(Hohai University,Grant Nos.2013B31614 and 2014B04114)
文摘Horizontal axis tidal turbines have attracted more and more attentions nowadays, because of their convenience and low expense in construction and high efficiency in extracting tidal energy. The present study numerically investigates the flow motion and performance of a horizontal axis tidal turbine with a supporting vertical cylinder under steady current. In the numerical model, the continuous equation and incompressible Reynolds-averaged Navier-Stokes equations are solved, and the volume of fluid method is employed to track free surface motion. The RNG k-ε model is adopted to calculate turbulence transport while the fractional area/volume obstacle representation method is used to describe turbine characteristics and movement. The effects of installation elevation of tidal turbine and inlet velocity on the water elevation, and current velocity, rotating speed and resultant force on turbine are discussed. Based on the comparison of the numerical results, a better understanding of flow structure around horizontal axis tidal turbine and turbine performance is achieved.
基金The authors are acknowledging the support of the H2020 program through the ConnectinGEO project.This project was funded by the EU FP for Research and Innovation(SC5-18a-2014-H2020)under grant agreement n°641538.
文摘Essential Variables are defined as a minimal set of variables that explain the state of the system.They are crucial for predicting its developments,and support metrics that measure its evolution.The variables should be relevant to meet requirements of stakeholders and be technically and economically feasible for systematic observation.A definition of Essential Renewable Energies Variables is proposed linked with their identification in several domains in renewable energy using a bottom-up and userdriven approach,and spanning over several years of documented interaction with stakeholders.Lists of variables are proposed in hydropower,solar,wind,and marine energies.It does not comprise the variables relating to social and economic aspects supporting decision making in investment nor those relating to civil engineering that are needed to erect a plant or farm.
