The recently modified EMC3-EIRENE code package has been widely applied as an edge-plasma analysis tool and resulted in successful validation against various measured trends seen in stellarator and tokamak plasma bound...The recently modified EMC3-EIRENE code package has been widely applied as an edge-plasma analysis tool and resulted in successful validation against various measured trends seen in stellarator and tokamak plasma boundaries.It has been shown that the code package applied for Wendelstein 7-X(W7-X)discharges in the interpretive mode can assess the impact of impurity effects on the electron density,measured by a set of Langmuir probes.In particular the spatial quantification of impurities and effects from the effective charge state Zeff and effective mass meff,which are non-trivial to record by diagnostics,were examined.The results showed that earlier assumptions of the effective charge-state distribution and effective mass for reported Langmuir probe measurements must be revised.Subsequently,reprocessing these measurements with code-interpreted spatial profiles of the effective charge state and effective mass led to an overall improved physical consistency.展开更多
Controlling the heat and particle fluxes in the plasma edge and on the plasma facing components is important for the safe and effective operation of every magnetically confined fusion device.This was attempted on Wend...Controlling the heat and particle fluxes in the plasma edge and on the plasma facing components is important for the safe and effective operation of every magnetically confined fusion device.This was attempted on Wendelstein 7-X in the first operational campaign,with the modification of the magnetic configuration by use of the trim coils and tuning the field coil currents,commonly named iota scan.Ideally,the heat loads on the five limiters are equal.However,they differ between each limiter and are non-uniform,due to the(relatively small) error fields caused by the misalignment of components.It is therefore necessary to study the influence of the configuration changes on the transport of heat and particles in the plasma edge caused by the application of error fields and the change of the magnetic configuration.In this paper the upstream measurements conducted with the combined probe are compared to the downstream measurements with the DIAS infrared camera on the limiter.展开更多
基金This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 under Grant Agreement No.633053.
文摘The recently modified EMC3-EIRENE code package has been widely applied as an edge-plasma analysis tool and resulted in successful validation against various measured trends seen in stellarator and tokamak plasma boundaries.It has been shown that the code package applied for Wendelstein 7-X(W7-X)discharges in the interpretive mode can assess the impact of impurity effects on the electron density,measured by a set of Langmuir probes.In particular the spatial quantification of impurities and effects from the effective charge state Zeff and effective mass meff,which are non-trivial to record by diagnostics,were examined.The results showed that earlier assumptions of the effective charge-state distribution and effective mass for reported Langmuir probe measurements must be revised.Subsequently,reprocessing these measurements with code-interpreted spatial profiles of the effective charge state and effective mass led to an overall improved physical consistency.
基金funding from the Euratom research and training program 2014–2018 under grant agreement No.633053
文摘Controlling the heat and particle fluxes in the plasma edge and on the plasma facing components is important for the safe and effective operation of every magnetically confined fusion device.This was attempted on Wendelstein 7-X in the first operational campaign,with the modification of the magnetic configuration by use of the trim coils and tuning the field coil currents,commonly named iota scan.Ideally,the heat loads on the five limiters are equal.However,they differ between each limiter and are non-uniform,due to the(relatively small) error fields caused by the misalignment of components.It is therefore necessary to study the influence of the configuration changes on the transport of heat and particles in the plasma edge caused by the application of error fields and the change of the magnetic configuration.In this paper the upstream measurements conducted with the combined probe are compared to the downstream measurements with the DIAS infrared camera on the limiter.