针对中小型河流引水式水电站下游减脱水河段的生态修复问题,总结了5种常用的生态流量过程计算方法,将物元分析法(Matter Element Analysis)与Tennant法耦合,提出了ME-Tennant河流生态流量过程评价模型。以湖南省刘家坪水电站为例,应用...针对中小型河流引水式水电站下游减脱水河段的生态修复问题,总结了5种常用的生态流量过程计算方法,将物元分析法(Matter Element Analysis)与Tennant法耦合,提出了ME-Tennant河流生态流量过程评价模型。以湖南省刘家坪水电站为例,应用该模型对不同方法计算出来的生态流量过程进行评价,最终以NGPRP法和年内展布法的计算结果确定最小生态流量过程,以2种不同保证率下的逐月频率法计算结果确定适宜生态流量过程,结果符合研究流域的生态水文特征。研究为推求河道生态流量过程提供了新思路,也为水电站下游减脱水河段的生态修复提供了参考。展开更多
Discharge branching is a general phenomenon in atmospheric-pressure air,dense gases,and two-phase mixtures(TPMs).In this work,an ultraviolet imaging device is utilized to investigate the branching of positive pulsed d...Discharge branching is a general phenomenon in atmospheric-pressure air,dense gases,and two-phase mixtures(TPMs).In this work,an ultraviolet imaging device is utilized to investigate the branching of positive pulsed discharges in TPMs.Comparison among the captured images indicates that the branching is caused by the voltages and the macropartilces in the discharge channels combining together.The interaction of macroparticles with ions,electrons or photons is one reason for the branching behavior of pulsed discharges.The generation of electrons at the discharge front closely relates to the work function of dielectric macroparticles,which is a key parameter influencing the electron-emission ability of macroparticle surfaces.The electric field alteration under various applied voltage in TPMs,which is calculated by a two-dimension finite element method,is the other reason for the guiding effect of macroparticles on the streamers compared with in the air.展开更多
文摘针对中小型河流引水式水电站下游减脱水河段的生态修复问题,总结了5种常用的生态流量过程计算方法,将物元分析法(Matter Element Analysis)与Tennant法耦合,提出了ME-Tennant河流生态流量过程评价模型。以湖南省刘家坪水电站为例,应用该模型对不同方法计算出来的生态流量过程进行评价,最终以NGPRP法和年内展布法的计算结果确定最小生态流量过程,以2种不同保证率下的逐月频率法计算结果确定适宜生态流量过程,结果符合研究流域的生态水文特征。研究为推求河道生态流量过程提供了新思路,也为水电站下游减脱水河段的生态修复提供了参考。
基金Project supported by National Natural Science Foundation of China(50237010),National Basic Research Program of China(973 Program)(2011CB209400)
文摘Discharge branching is a general phenomenon in atmospheric-pressure air,dense gases,and two-phase mixtures(TPMs).In this work,an ultraviolet imaging device is utilized to investigate the branching of positive pulsed discharges in TPMs.Comparison among the captured images indicates that the branching is caused by the voltages and the macropartilces in the discharge channels combining together.The interaction of macroparticles with ions,electrons or photons is one reason for the branching behavior of pulsed discharges.The generation of electrons at the discharge front closely relates to the work function of dielectric macroparticles,which is a key parameter influencing the electron-emission ability of macroparticle surfaces.The electric field alteration under various applied voltage in TPMs,which is calculated by a two-dimension finite element method,is the other reason for the guiding effect of macroparticles on the streamers compared with in the air.