Grate process is an important step in grate-kiln pellet production.However,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to control.As a result,mathematica...Grate process is an important step in grate-kiln pellet production.However,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to control.As a result,mathematical models of temperature distribution,moisture distribution and oxidation degree distribution in pellet bed,with good universality,computation speed and calculation accuracy,are presented based on analysis of heat transfer and physical-chemical reactions during grate process.And real-time visualization of temperature,moisture and oxidation degree distribution in pellet bed during grate process is realized.Model validation is displayed,and the similarity of 91% is proved.The results can reveal real time status on grate,and provide a solid foundation for the subsequent study of artificial intelligence control system of pellet production.展开更多
Rotary kiln process for iron ore oxide pellet production is hard to detect and control.Construction of one-dimensional model of temperature field in rotary kiln was described.And the results lay a solid foundation for...Rotary kiln process for iron ore oxide pellet production is hard to detect and control.Construction of one-dimensional model of temperature field in rotary kiln was described.And the results lay a solid foundation for online control.Establishment of kiln process control expert system was presented,with maximum temperature of pellet and gas temperature at the feed end as control cores,and interval estimate as control strategy.Software was developed and put into application in a pellet plant.The results show that control guidance of this system is accurate and effective.After production application for nearly one year,the compressive strength and first grade rate of pellet are increased by 86 N and 2.54%,respectively,while FeO content is 0.05% lowered.This system can reveal detailed information of real time kiln process,and provide a powerful tool for online control of pellet production.展开更多
We have compiled a list of all planet host star candidates reported in the literature,which are likely to be cluster members,and we checked their memberships by the spatial location,radial velocity,proper motion and p...We have compiled a list of all planet host star candidates reported in the literature,which are likely to be cluster members,and we checked their memberships by the spatial location,radial velocity,proper motion and photometric criteria.We found that only six stars,BD-13 2130,HD 28305,Kepler-66,Kepler-67,Pr0201 and Pr0211,are planet orbiting stars in open clusters to date.Two stars,HD 70573 and HD 89744,belong to moving groups and one star,TYC 8975-2606-1,may not be a planet host star,while three stars,HD 16175,HD 46375 and HD 108874 are not members of open clusters.We note that all these six planetary systems in the stellar cluster environment are younger than^1 Gyr,which might indicate that the planetary system in open cluster can not survive for a long time,and we speculate that close stellar encounters between member stars in open cluster can potentially destroy,or at least strongly affect,the presence of planetary systems.展开更多
基金Project(NCET050630) supported by Program for New Century Excellent Talents in University,China
文摘Grate process is an important step in grate-kiln pellet production.However,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to control.As a result,mathematical models of temperature distribution,moisture distribution and oxidation degree distribution in pellet bed,with good universality,computation speed and calculation accuracy,are presented based on analysis of heat transfer and physical-chemical reactions during grate process.And real-time visualization of temperature,moisture and oxidation degree distribution in pellet bed during grate process is realized.Model validation is displayed,and the similarity of 91% is proved.The results can reveal real time status on grate,and provide a solid foundation for the subsequent study of artificial intelligence control system of pellet production.
基金Project(NCET-05-0630) supported by Program for New Century Excellent Talents in University of China
文摘Rotary kiln process for iron ore oxide pellet production is hard to detect and control.Construction of one-dimensional model of temperature field in rotary kiln was described.And the results lay a solid foundation for online control.Establishment of kiln process control expert system was presented,with maximum temperature of pellet and gas temperature at the feed end as control cores,and interval estimate as control strategy.Software was developed and put into application in a pellet plant.The results show that control guidance of this system is accurate and effective.After production application for nearly one year,the compressive strength and first grade rate of pellet are increased by 86 N and 2.54%,respectively,while FeO content is 0.05% lowered.This system can reveal detailed information of real time kiln process,and provide a powerful tool for online control of pellet production.
基金supported by the National Natural Science Foundation of China(Grant Nos.11390371,11233004 and 11222326)the National Key Basic Research Program of China(Grant No.2014CB845703)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB01020300)
文摘We have compiled a list of all planet host star candidates reported in the literature,which are likely to be cluster members,and we checked their memberships by the spatial location,radial velocity,proper motion and photometric criteria.We found that only six stars,BD-13 2130,HD 28305,Kepler-66,Kepler-67,Pr0201 and Pr0211,are planet orbiting stars in open clusters to date.Two stars,HD 70573 and HD 89744,belong to moving groups and one star,TYC 8975-2606-1,may not be a planet host star,while three stars,HD 16175,HD 46375 and HD 108874 are not members of open clusters.We note that all these six planetary systems in the stellar cluster environment are younger than^1 Gyr,which might indicate that the planetary system in open cluster can not survive for a long time,and we speculate that close stellar encounters between member stars in open cluster can potentially destroy,or at least strongly affect,the presence of planetary systems.