Fully nonlinear wave-body interactions for a surface-piercing structure with combined wave-current flow in different water depths are studied by using a 2-D numerical tank. The model is based on Reynolds averaged Navi...Fully nonlinear wave-body interactions for a surface-piercing structure with combined wave-current flow in different water depths are studied by using a 2-D numerical tank. The model is based on Reynolds averaged Navier-Stokes （RANS） equations and renormalization group （RNG） k- E model. The mean and maximum wave-current impacts, including forces in two directions and rotational moment, are calculated and discussed. The effects of U/C and water depth condition on forces and moment have been investigated and the results for combined irregular waves and waves and currents. currents are compared with those induced by combined regular展开更多
A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power ca...A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.展开更多
The planning environmental impact assessment （EIA） of transmission and transformation power grid at levels of 500 and 220 kV had been finished completely in the 13 municipalities of Jiangsu Province by the end of 20...The planning environmental impact assessment （EIA） of transmission and transformation power grid at levels of 500 and 220 kV had been finished completely in the 13 municipalities of Jiangsu Province by the end of 2012, which played important roles in guiding and planning the following transmission and transformation projects in environmental protection. In this paper, through the detail analysis on the objective and significance of the planning EIA of transmission and transformation power grid, legal basis and planning EIA practices, some suggestions and thinking about the planning EIA of transmission and transformation power grid were put forward.展开更多
The sea area east of Chenshan Cape has peak tidal current flows that exceed 2.3 m s^-1,which make it a promising site for the development of tidal current energy.Before these resources can be exploited,a comprehensive...The sea area east of Chenshan Cape has peak tidal current flows that exceed 2.3 m s^-1,which make it a promising site for the development of tidal current energy.Before these resources can be exploited,a comprehensive assessment is needed of the potential environmental impacts of the extraction of this energy.In this paper,we describe our construction of a three-dimensional hydrodynamic model of the waters near Chengshan Cape,and verify the performance of the model using continuous data measured in situ.We modeled the potential impacts of the exploitation of these resources on the flow field by adding a momentum loss term in the governing equation of the model.Simulation results show that an assumed tidal farm with an estimated power output of 20.34 MW would have a significant impact on the surrounding water level,especially next to the farm,where fluctuation could reach 6 cm.The maximum drop in the flow velocity in the wake of the farm was predicted to be more than 0.8 m s^-1,and this influence would extend 10 km downstream.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.11032007)the Key Instrument Developing Project of the Chinese Academy of Sciences(Grant No.ZDYZ2012-1-08-02)
文摘Fully nonlinear wave-body interactions for a surface-piercing structure with combined wave-current flow in different water depths are studied by using a 2-D numerical tank. The model is based on Reynolds averaged Navier-Stokes （RANS） equations and renormalization group （RNG） k- E model. The mean and maximum wave-current impacts, including forces in two directions and rotational moment, are calculated and discussed. The effects of U/C and water depth condition on forces and moment have been investigated and the results for combined irregular waves and waves and currents. currents are compared with those induced by combined regular
基金supported by National Key R&D Project under Grant(2018YFB0904400).
文摘A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.
基金Supported by the National Key Technology R&D Program(2012BAC20B1003)the Key National Social Science Fund Project(12&ZD214)the Special Fund Project for the Scientific Research of the Environmental Protection Welfare Industry(201209001)
文摘The planning environmental impact assessment （EIA） of transmission and transformation power grid at levels of 500 and 220 kV had been finished completely in the 13 municipalities of Jiangsu Province by the end of 2012, which played important roles in guiding and planning the following transmission and transformation projects in environmental protection. In this paper, through the detail analysis on the objective and significance of the planning EIA of transmission and transformation power grid, legal basis and planning EIA practices, some suggestions and thinking about the planning EIA of transmission and transformation power grid were put forward.
基金supported by the National Natural Science Foundation of China (No. 51479185)the Major Basic Research Project of Shandong Province (No. ZR 2017ZA0202)
文摘The sea area east of Chenshan Cape has peak tidal current flows that exceed 2.3 m s^-1,which make it a promising site for the development of tidal current energy.Before these resources can be exploited,a comprehensive assessment is needed of the potential environmental impacts of the extraction of this energy.In this paper,we describe our construction of a three-dimensional hydrodynamic model of the waters near Chengshan Cape,and verify the performance of the model using continuous data measured in situ.We modeled the potential impacts of the exploitation of these resources on the flow field by adding a momentum loss term in the governing equation of the model.Simulation results show that an assumed tidal farm with an estimated power output of 20.34 MW would have a significant impact on the surrounding water level,especially next to the farm,where fluctuation could reach 6 cm.The maximum drop in the flow velocity in the wake of the farm was predicted to be more than 0.8 m s^-1,and this influence would extend 10 km downstream.
