Macro-instability(MI)is an important natural phenomenon affecting the mixing performance in stirred tank significantly,which results from movement and evolution of large eddies.Factors associated with MI frequency in ...Macro-instability(MI)is an important natural phenomenon affecting the mixing performance in stirred tank significantly,which results from movement and evolution of large eddies.Factors associated with MI frequency in mixing operation and energy dissipation related to MI were reviewed.Flow pattern in turbulent regime contains many coherent structures,which have much energy vortices and may result in flow field MI.Adjustment of coherent structure and controlling MI may contribute to energy saving and good mixing performance.Controlling methods for MI was prospected.展开更多
The next generation fusion device listed on ENN’s fusion roadmap,named as(ENN He-Long)EHL-2,is under both physics and engineering designs.The instabilities of ideal magnetohydrodynamics(MHD)mode and neoclassical tear...The next generation fusion device listed on ENN’s fusion roadmap,named as(ENN He-Long)EHL-2,is under both physics and engineering designs.The instabilities of ideal magnetohydrodynamics(MHD)mode and neoclassical tearing mode(NTM)stabilized by electron cyclotron current drive(ECCD)for EHL-2’s two typical operation scenarios are analyzed.For high-ion-temperature operating(HITO)scenario,the vertical displacement event(VDE)could be a big challenge to the device safety.For the steady-state operating(SSO)scenario,the limitation may rise from the ideal MHD mode,NTM,etc.This suggests that the MHD analysis of both operation scenarios should be done with different focusing.Preliminary analysis based on the current physics and engineering design of both two scenarios is given in this paper.Based on the analysis result of above,the future assessments might target at active control method and the effect of boron on MHD activities.展开更多
Chaotic mixing is regarded as an effective method to improve the mixing effect in the laminar stirred tank.To generate chaos in flow field in stirred tank,many efforts including aperiodic movement,asystematic installa...Chaotic mixing is regarded as an effective method to improve the mixing effect in the laminar stirred tank.To generate chaos in flow field in stirred tank,many efforts including aperiodic movement,asystematic installation impeller,etc.,were made to save mixing time and energy consumption.The computational fluid dynamics of chaotic flow field and the hyperchaotic controlling method as well as macro-instability were reviewed.Multiple flow field coupling is important in the turbulent mixing region of stirred tank.The development trends of flow field coupling and hyperchaotic controlling in chaotic mixing were prospected in energy saving operation.展开更多
基金financially supported by Natural Science Foundation of China(20806095)ScientificResearch Foundation for the Returned Overseas Chinese Scholars,State Education Ministry(教外司留20091341-2)+1 种基金China Postdoctoral Science Foundation(20080430747)National High Technology Researchand Development Program of China(2008AA031202)
文摘Macro-instability(MI)is an important natural phenomenon affecting the mixing performance in stirred tank significantly,which results from movement and evolution of large eddies.Factors associated with MI frequency in mixing operation and energy dissipation related to MI were reviewed.Flow pattern in turbulent regime contains many coherent structures,which have much energy vortices and may result in flow field MI.Adjustment of coherent structure and controlling MI may contribute to energy saving and good mixing performance.Controlling methods for MI was prospected.
文摘The next generation fusion device listed on ENN’s fusion roadmap,named as(ENN He-Long)EHL-2,is under both physics and engineering designs.The instabilities of ideal magnetohydrodynamics(MHD)mode and neoclassical tearing mode(NTM)stabilized by electron cyclotron current drive(ECCD)for EHL-2’s two typical operation scenarios are analyzed.For high-ion-temperature operating(HITO)scenario,the vertical displacement event(VDE)could be a big challenge to the device safety.For the steady-state operating(SSO)scenario,the limitation may rise from the ideal MHD mode,NTM,etc.This suggests that the MHD analysis of both operation scenarios should be done with different focusing.Preliminary analysis based on the current physics and engineering design of both two scenarios is given in this paper.Based on the analysis result of above,the future assessments might target at active control method and the effect of boron on MHD activities.
基金supported by Natural Science Foundation of China(20806095)ScientificResearch Foundation for the Returned Overseas Chinese Scholars,State Education Ministry(教外司留20091341-2)+1 种基金China Postdoctoral Science Foundation(20080430747)National High Technology Research and Development Program of China(2008AA0312)
文摘Chaotic mixing is regarded as an effective method to improve the mixing effect in the laminar stirred tank.To generate chaos in flow field in stirred tank,many efforts including aperiodic movement,asystematic installation impeller,etc.,were made to save mixing time and energy consumption.The computational fluid dynamics of chaotic flow field and the hyperchaotic controlling method as well as macro-instability were reviewed.Multiple flow field coupling is important in the turbulent mixing region of stirred tank.The development trends of flow field coupling and hyperchaotic controlling in chaotic mixing were prospected in energy saving operation.
