目前海上油田电泵系统的动力驱动部分为传统潜油三相异步电机,电机单位长度功率较低,100 Hp 456系列电机长度接近10 m左右,大功率电机只能串接,不仅浪费海上作业时间,而且有电气连接风险。为缩短电机,提高电机性能,迫切需要对现有技术...目前海上油田电泵系统的动力驱动部分为传统潜油三相异步电机,电机单位长度功率较低,100 Hp 456系列电机长度接近10 m左右,大功率电机只能串接,不仅浪费海上作业时间,而且有电气连接风险。为缩短电机,提高电机性能,迫切需要对现有技术进行升级改进,通过优化电磁方案,提高电机单位长度功率密度,降低成本。本文经过对四种方案的设计输出对比,结合温升计算,选出来一种最优方案,相比原设计单位长度功率提升79.6%,单位长度扭矩提升53%。展开更多
In the flotation process, bubble is a key factor in studying bubble-particle interaction and fine particle flo- tation. Knowledge on size distribution of bubbles in a flotation system is highly important. In this stud...In the flotation process, bubble is a key factor in studying bubble-particle interaction and fine particle flo- tation. Knowledge on size distribution of bubbles in a flotation system is highly important. In this study, bubble distributions in different reagent concentrations, electrolyte concentrations, cathode apertures, and current densities in electroflotation are determined using a high-speed camera. Average bubble sizes under different conditions are calculated using Image-Pro@ Plus （Media Cybernetics@, MD, USA） and SigmaScan@ Pro （Systat Software, CA, USA） software. Results indicate that the average sizes of bubbles, which were generated through 38, 50, 74, 150, 250, 420, and 1000 μm cathode apertures, are 20.2, 29.5, 44.6, 59.2, 68.7, 78.5, and 88.8 μm, respectively. The optimal current density in electroflotation is 20 A/m2. Reagent and electrolyte concentrations, current density, and cathode aperture are important factors in controlling bubble size and nucleation. These factors also contribute to the control of fine- Particle flotation.展开更多
Highly porous carbon, both unmodified and hexamine-coated on the pore surfaces, is tested at high working voltages in organic electrolyte for supercapacitors in order to enhance the energy density and power density.So...Highly porous carbon, both unmodified and hexamine-coated on the pore surfaces, is tested at high working voltages in organic electrolyte for supercapacitors in order to enhance the energy density and power density.Sol–gel processing allows for excellent control of the porous structure and chemical composition of carbon,resulting in a material with high surface area and a low level of impurities. This porous carbon can be modified using a simple solution-based method to enhance capacitance. Increasing the working voltage from 2.0 to 3.0 V significantly improves performance for both unmodified and hexamine-coated carbon. The energy density and power density increase at higher working voltage, and under certain conditions, the capacitance increases as well.Cyclic stability is also investigated, with hexamine-coated carbon retaining more of its initial capacitance than unmodified carbon at all working voltages.展开更多
文摘目前海上油田电泵系统的动力驱动部分为传统潜油三相异步电机,电机单位长度功率较低,100 Hp 456系列电机长度接近10 m左右,大功率电机只能串接,不仅浪费海上作业时间,而且有电气连接风险。为缩短电机,提高电机性能,迫切需要对现有技术进行升级改进,通过优化电磁方案,提高电机单位长度功率密度,降低成本。本文经过对四种方案的设计输出对比,结合温升计算,选出来一种最优方案,相比原设计单位长度功率提升79.6%,单位长度扭矩提升53%。
基金the National Natural Science Foundation of China (No.50774094)the Ministry of Science and Technology of China (No.2011BAB05B01) for financial support
文摘In the flotation process, bubble is a key factor in studying bubble-particle interaction and fine particle flo- tation. Knowledge on size distribution of bubbles in a flotation system is highly important. In this study, bubble distributions in different reagent concentrations, electrolyte concentrations, cathode apertures, and current densities in electroflotation are determined using a high-speed camera. Average bubble sizes under different conditions are calculated using Image-Pro@ Plus （Media Cybernetics@, MD, USA） and SigmaScan@ Pro （Systat Software, CA, USA） software. Results indicate that the average sizes of bubbles, which were generated through 38, 50, 74, 150, 250, 420, and 1000 μm cathode apertures, are 20.2, 29.5, 44.6, 59.2, 68.7, 78.5, and 88.8 μm, respectively. The optimal current density in electroflotation is 20 A/m2. Reagent and electrolyte concentrations, current density, and cathode aperture are important factors in controlling bubble size and nucleation. These factors also contribute to the control of fine- Particle flotation.
基金supported by the National Science Foundation(CMMI-1030048)University of Washington’s IGERT:Bioresource-based Energy for Sustainable Societies(DGE-0654252)the Intel Corporation.Part of this work was conducted at the University of Washington Nano Tech User Facility,a member of the National Science Foundation National Nanotechnology Infrastructure Network(NNIN)
文摘Highly porous carbon, both unmodified and hexamine-coated on the pore surfaces, is tested at high working voltages in organic electrolyte for supercapacitors in order to enhance the energy density and power density.Sol–gel processing allows for excellent control of the porous structure and chemical composition of carbon,resulting in a material with high surface area and a low level of impurities. This porous carbon can be modified using a simple solution-based method to enhance capacitance. Increasing the working voltage from 2.0 to 3.0 V significantly improves performance for both unmodified and hexamine-coated carbon. The energy density and power density increase at higher working voltage, and under certain conditions, the capacitance increases as well.Cyclic stability is also investigated, with hexamine-coated carbon retaining more of its initial capacitance than unmodified carbon at all working voltages.
