The transport properties of gluon in color space in a system of coexistence of both hadronic and QGP phases are investigated from the quantum transport equation of gluon.
The three levels optimizing strategy is put forward for the networked manufacturing resources optimizing configuration, namely, the optimizing of a logical manufacturing process, the optimizing of simulation-based int...The three levels optimizing strategy is put forward for the networked manufacturing resources optimizing configuration, namely, the optimizing of a logical manufacturing process, the optimizing of simulation-based integration of process planning and scheduling, and the optimizing of networked production scheduling. Then, the web services-based architecture of networked manufacturing resources optimizing configuration is brought forward. Finally, the key algorithm of the networked manufacturing resources optimizing configuration is discussed, namely, the two phases manufacturing partners selection method, which including the group technology-based manufacturing resources pre-configuration and the genetic algorithm-based executable manufacturing process optimizing.展开更多
Structured packing is a good candidate for CO2 capture process because of its higher mass transfer efficiency and lower pressure drop. Now, the challenging problem of CO2 capture and storage demands more and more effi...Structured packing is a good candidate for CO2 capture process because of its higher mass transfer efficiency and lower pressure drop. Now, the challenging problem of CO2 capture and storage demands more and more efficiency equipment. The aim of the present study is to investigate the liquid film characteristics under counter current gas phase and throw some insight into the enhancing mechanism of mass transfer performance in structured packing. A high speed digital camera, non-intrusive measurement technique, was used. Water and air were working fluids. Experiments were carried out for different gas/liquid flow rates and different inclination angles. The time-average and instantaneous film widths for each set of flow parameters were calculated. It is shown that the effects of gas phase could be neglected for lower flow rate, and then, become more pronounced at higher flow rate. According to instantaneous film width, three different stages can be distinguished. One is the constant width of liquid film. The second is the slight decrease of film width and the smooth surface. This kind of character will lead to less interfacial area and deteriorate the packing mass transfer performance. For the third stage, the variation of film width shows clearly chaotic behavior. The prediction model was also developed in present work. The predicted and experimental results are in good agreement.展开更多
An innovative steelmaking process is suggested using an electromagnetic driven swirling flow in the up-leg of an RH vacuum degasser.A physical and a mathematical model based on 300t RH vacuum degasser are developed to...An innovative steelmaking process is suggested using an electromagnetic driven swirling flow in the up-leg of an RH vacuum degasser.A physical and a mathematical model based on 300t RH vacuum degasser are developed to understand the effect of rotating electromagnetic field on the circulation flow rate and the two phases flow behavior of RH system.Both water model experiments and numerical simulation show the flow pattern and distribution of gas bubbles. The gas bubbles move towards the centre of up-leg under the effect of rotating electromagnetic field,and the accumulation of gas bubbles depends on the magnetic intensity.An optimization value of magnetic intensity was suggested in this paper.展开更多
Circuits with switched current are described by an admittance matrix and seeking current transfers then means calculating the ratio of algebraic supplements of this matrix. As there are also graph methods of circuit a...Circuits with switched current are described by an admittance matrix and seeking current transfers then means calculating the ratio of algebraic supplements of this matrix. As there are also graph methods of circuit analysis in addition to algebraic methods, it is clearly possible in theory to carry out an analysis of the whole switched circuit in two-phase switching exclusively by the graph method as well. For this purpose it is possible to plot a Mason graph of a circuit, use transformation graphs to reduce Mason graphs for all the four phases of switching, and then plot a summary graph from the transformed graphs obtained this way. First the author draws nodes and possible branches, obtained by transformation graphs for transfers of EE (even-even) and OO (odd-odd) phases. In the next step, branches obtained by transformation graphs for EO and OE phase are drawn between these nodes, while their resulting transfer is 1 multiplied by z^1/2. This summary graph is extended by two branches from input node and to output node, the extended graph can then be interpreted by the Mason's relation to provide transparent current transfers. Therefore it is not necessary to compose a sum admittance matrix and to express this consequently in numbers, and so it is possible to reach the final result in a graphical way.展开更多
The anti-cavitation performance of a high-speed centrifugal pump with a splitter-bladed inducer is investigated under different flow rates and different inlet pressures. Simulations and external characteristics experi...The anti-cavitation performance of a high-speed centrifugal pump with a splitter-bladed inducer is investigated under different flow rates and different inlet pressures. Simulations and external characteristics experiments are carried out. Static pressure and the vapor volume fraction distributions on the inducer and the impeller of the pump under various operation conditions are obtained. The results show that the cavitation developments on the impeller and on the inducer with the flow rates are reverse, while the development of the inlet pressure on the inducer and the impeller is the same. Cavitation on the impeller increases with the increase of flow rates, and it extends to the near passages with rotating, while cavitation on the inducer is more complex than that on the impeller. Cavitation at the inlet of the inducer decreases with the increase of flow rates, while cavitation at the outlet of the inducer is opposite. The results also show that cavitation development on the impeller and on the inducer with the inlet pressure is the same. Cavitation both decreases with the increase of the inlet pressure at the same flow rate. Furthermore, asymmetric cavitation on the impeller and on the inducer is both observed. And the asymmetric degree of cavitation on the impeller is higher than that on the inducer.展开更多
The hydrodynamics in a gas-solid airlift loop reactor was investigated systematically using experimental measurements and CFD simulation. In the experiments, the time averaged parameters, such as solid frac- tion and ...The hydrodynamics in a gas-solid airlift loop reactor was investigated systematically using experimental measurements and CFD simulation. In the experiments, the time averaged parameters, such as solid frac- tion and particle velocity, were measured by optical fiber probe. In the simulation, the modified Gidaspow drag model accounting for the interparticles clustering was incorporated into the Eulerian-Eulerian CFD model with particulate-phase kinetic theory. Predicted values of solid fraction and particle velocity were compared with experimental results, validating the drag model and the simulation. The results show that the profiles of particle velocity and solid fraction are uniform in annulus. However, the core-annulus structure appears in other three regions (draft tube region, bottom region and particle diffluence region), which presents the similar heterogeneous feature of aggregative fluidization usually occurred in nor- mal fiuidized beds. Simulated profiles of particle residence time distribution indicate that the airlift loop reactor should be characterized by near perfect mixing.展开更多
Liquid film flow is very important in many industrial applications.However,there are few reports about its characteristics on structured packings.Therefore,in this paper,liquid film phenomena were investigated experim...Liquid film flow is very important in many industrial applications.However,there are few reports about its characteristics on structured packings.Therefore,in this paper,liquid film phenomena were investigated experimentally to exploit new approaches for intensifying the performance of the structured packings.All experi-ments were performed at room temperature.Water and air were the working fluids.The effect of counter current gas phase on the liquid film was taken into consideration.A high speed camera,a non-intrusive measurement techni-que,was used.It is shown that both liquid and gas phases have strong effects on film characteristics.In the present work,liquid film width increased by 57% because of increasing liquid flow rate,while it decreased by 25%resulting from the counter current gas phase.展开更多
基金National Natural Science Foundation of China,the Foundation of Harbin Institute of Technology
文摘The transport properties of gluon in color space in a system of coexistence of both hadronic and QGP phases are investigated from the quantum transport equation of gluon.
基金This paper is supported by National High-Tech R&D Program for CIMS, China (Grant No. 2003AA411110) theNational Research Foundation for Doctoral Program of Higher Education, China (Grant No. 20040699025).
文摘The three levels optimizing strategy is put forward for the networked manufacturing resources optimizing configuration, namely, the optimizing of a logical manufacturing process, the optimizing of simulation-based integration of process planning and scheduling, and the optimizing of networked production scheduling. Then, the web services-based architecture of networked manufacturing resources optimizing configuration is brought forward. Finally, the key algorithm of the networked manufacturing resources optimizing configuration is discussed, namely, the two phases manufacturing partners selection method, which including the group technology-based manufacturing resources pre-configuration and the genetic algorithm-based executable manufacturing process optimizing.
基金Supported by the National Natural Science Foundation of China (20070003154), the National High Technology Research and Development Program of China (2006AA05Z316, 2006AA030202), the Specialized Research Fund for Doctoral Program of Higher Education of China (20070003154), and the Key Program for International Cooperation of Science and Technology, China (2001CB711203).
文摘Structured packing is a good candidate for CO2 capture process because of its higher mass transfer efficiency and lower pressure drop. Now, the challenging problem of CO2 capture and storage demands more and more efficiency equipment. The aim of the present study is to investigate the liquid film characteristics under counter current gas phase and throw some insight into the enhancing mechanism of mass transfer performance in structured packing. A high speed digital camera, non-intrusive measurement technique, was used. Water and air were working fluids. Experiments were carried out for different gas/liquid flow rates and different inclination angles. The time-average and instantaneous film widths for each set of flow parameters were calculated. It is shown that the effects of gas phase could be neglected for lower flow rate, and then, become more pronounced at higher flow rate. According to instantaneous film width, three different stages can be distinguished. One is the constant width of liquid film. The second is the slight decrease of film width and the smooth surface. This kind of character will lead to less interfacial area and deteriorate the packing mass transfer performance. For the third stage, the variation of film width shows clearly chaotic behavior. The prediction model was also developed in present work. The predicted and experimental results are in good agreement.
基金Item Sponsored by National Natural Science Foundation of China[No.51004029]
文摘An innovative steelmaking process is suggested using an electromagnetic driven swirling flow in the up-leg of an RH vacuum degasser.A physical and a mathematical model based on 300t RH vacuum degasser are developed to understand the effect of rotating electromagnetic field on the circulation flow rate and the two phases flow behavior of RH system.Both water model experiments and numerical simulation show the flow pattern and distribution of gas bubbles. The gas bubbles move towards the centre of up-leg under the effect of rotating electromagnetic field,and the accumulation of gas bubbles depends on the magnetic intensity.An optimization value of magnetic intensity was suggested in this paper.
文摘Circuits with switched current are described by an admittance matrix and seeking current transfers then means calculating the ratio of algebraic supplements of this matrix. As there are also graph methods of circuit analysis in addition to algebraic methods, it is clearly possible in theory to carry out an analysis of the whole switched circuit in two-phase switching exclusively by the graph method as well. For this purpose it is possible to plot a Mason graph of a circuit, use transformation graphs to reduce Mason graphs for all the four phases of switching, and then plot a summary graph from the transformed graphs obtained this way. First the author draws nodes and possible branches, obtained by transformation graphs for transfers of EE (even-even) and OO (odd-odd) phases. In the next step, branches obtained by transformation graphs for EO and OE phase are drawn between these nodes, while their resulting transfer is 1 multiplied by z^1/2. This summary graph is extended by two branches from input node and to output node, the extended graph can then be interpreted by the Mason's relation to provide transparent current transfers. Therefore it is not necessary to compose a sum admittance matrix and to express this consequently in numbers, and so it is possible to reach the final result in a graphical way.
基金supported by the National Natural Science Foundation of China(Grant No.51406185)China Scholarship Council Project in 2012(Grant No.201208330325)+1 种基金the Third Level 151 Talent Project in Zhejiang Provincethe Professional Leader Leading Project in 2013(Grant No.lj2013005)
文摘The anti-cavitation performance of a high-speed centrifugal pump with a splitter-bladed inducer is investigated under different flow rates and different inlet pressures. Simulations and external characteristics experiments are carried out. Static pressure and the vapor volume fraction distributions on the inducer and the impeller of the pump under various operation conditions are obtained. The results show that the cavitation developments on the impeller and on the inducer with the flow rates are reverse, while the development of the inlet pressure on the inducer and the impeller is the same. Cavitation on the impeller increases with the increase of flow rates, and it extends to the near passages with rotating, while cavitation on the inducer is more complex than that on the impeller. Cavitation at the inlet of the inducer decreases with the increase of flow rates, while cavitation at the outlet of the inducer is opposite. The results also show that cavitation development on the impeller and on the inducer with the inlet pressure is the same. Cavitation both decreases with the increase of the inlet pressure at the same flow rate. Furthermore, asymmetric cavitation on the impeller and on the inducer is both observed. And the asymmetric degree of cavitation on the impeller is higher than that on the inducer.
基金supports by the National Natural Science Foundation of China(Grant Nos.20806090,20976190and20776155).
文摘The hydrodynamics in a gas-solid airlift loop reactor was investigated systematically using experimental measurements and CFD simulation. In the experiments, the time averaged parameters, such as solid frac- tion and particle velocity, were measured by optical fiber probe. In the simulation, the modified Gidaspow drag model accounting for the interparticles clustering was incorporated into the Eulerian-Eulerian CFD model with particulate-phase kinetic theory. Predicted values of solid fraction and particle velocity were compared with experimental results, validating the drag model and the simulation. The results show that the profiles of particle velocity and solid fraction are uniform in annulus. However, the core-annulus structure appears in other three regions (draft tube region, bottom region and particle diffluence region), which presents the similar heterogeneous feature of aggregative fluidization usually occurred in nor- mal fiuidized beds. Simulated profiles of particle residence time distribution indicate that the airlift loop reactor should be characterized by near perfect mixing.
基金This research was carried out under the National High Technology Research and Development Programmes of China(Nos.2006AA05Z316,2006AA030202)the Specialised Research Fund for Doctoral Program of Higher Education of China(No.20070003154)in the State Key Laboratory of Chemical Engineering of Tsinghua University,Beijing,P.R.China.
文摘Liquid film flow is very important in many industrial applications.However,there are few reports about its characteristics on structured packings.Therefore,in this paper,liquid film phenomena were investigated experimentally to exploit new approaches for intensifying the performance of the structured packings.All experi-ments were performed at room temperature.Water and air were the working fluids.The effect of counter current gas phase on the liquid film was taken into consideration.A high speed camera,a non-intrusive measurement techni-que,was used.It is shown that both liquid and gas phases have strong effects on film characteristics.In the present work,liquid film width increased by 57% because of increasing liquid flow rate,while it decreased by 25%resulting from the counter current gas phase.