The flow dynamics in a novel fast-turbulent fluidized bed （FTFB） with middle-upper expanding structure and two different ring-feeder internals （mixed and vortex ring-feeder） were studied to achieve a reduction in ...The flow dynamics in a novel fast-turbulent fluidized bed （FTFB） with middle-upper expanding structure and two different ring-feeder internals （mixed and vortex ring-feeder） were studied to achieve a reduction in gasoline olefin production, Compared with a conventional circulating fluidized bed, the novel FTFB displayed unique characteristics and advantages. A higher solids holdup and more uniform solids holdup distribution existed in the diameter-expanding region, especially for the FTFB with vortex ring-feeder structure, A probability density distribution analysis indicated that the novel fluidized bed could reduce gas-solids segregation and enhance gas-solids interaction. A constant carbon dioxide tracer system was used to simulate the reactant gas distribution. The gas-solids contact efficiency was defined according to the solid dispersibility and the amount of gas covering the solid surface. Novel FTFB risers, especially those with vortex ring-feeders, have a much higher gas-solids contact efficiency than that of traditional risers.展开更多
针对电缆单环网故障定位问题,本文以行波理论为基础,对10kV电缆单环网在线故障定位系统进行研究。通过对电缆单环网结构进行分析,将单环网分为不同级别的T型组合单元,对每个T型电缆单元提出具体测距原理及算法,同时对所有的T型单元依次...针对电缆单环网故障定位问题,本文以行波理论为基础,对10kV电缆单环网在线故障定位系统进行研究。通过对电缆单环网结构进行分析,将单环网分为不同级别的T型组合单元,对每个T型电缆单元提出具体测距原理及算法,同时对所有的T型单元依次进行测距并统计分析测距结果,汇总后得到单环网的测距结果,并利用电力系统仿真软件(power system computer aided design,PSCAD)对T型单元故障进行仿真,仿真结果验证了算法和判据的可行性与正确性;最后对电缆单环网在线故障定位系统的硬件和软件进行设计。该系统可以实现对10kV电缆单环网故障的在线监测和定位,与其他测距装置相比,可以快速准确地找到故障点,从而减少停电检修时间,确保供电可靠性,有利于提高经济效益。展开更多
基金the financial support of the CNPC in the National Program on Key Basic Research Project(973 Program) of China(No.2012CB215000)
文摘The flow dynamics in a novel fast-turbulent fluidized bed （FTFB） with middle-upper expanding structure and two different ring-feeder internals （mixed and vortex ring-feeder） were studied to achieve a reduction in gasoline olefin production, Compared with a conventional circulating fluidized bed, the novel FTFB displayed unique characteristics and advantages. A higher solids holdup and more uniform solids holdup distribution existed in the diameter-expanding region, especially for the FTFB with vortex ring-feeder structure, A probability density distribution analysis indicated that the novel fluidized bed could reduce gas-solids segregation and enhance gas-solids interaction. A constant carbon dioxide tracer system was used to simulate the reactant gas distribution. The gas-solids contact efficiency was defined according to the solid dispersibility and the amount of gas covering the solid surface. Novel FTFB risers, especially those with vortex ring-feeders, have a much higher gas-solids contact efficiency than that of traditional risers.
文摘针对电缆单环网故障定位问题,本文以行波理论为基础,对10kV电缆单环网在线故障定位系统进行研究。通过对电缆单环网结构进行分析,将单环网分为不同级别的T型组合单元,对每个T型电缆单元提出具体测距原理及算法,同时对所有的T型单元依次进行测距并统计分析测距结果,汇总后得到单环网的测距结果,并利用电力系统仿真软件(power system computer aided design,PSCAD)对T型单元故障进行仿真,仿真结果验证了算法和判据的可行性与正确性;最后对电缆单环网在线故障定位系统的硬件和软件进行设计。该系统可以实现对10kV电缆单环网故障的在线监测和定位,与其他测距装置相比,可以快速准确地找到故障点,从而减少停电检修时间,确保供电可靠性,有利于提高经济效益。
