Abstract
The role of the boundary plasma in determining the power and particle balance of tokamak discharges is discussed. Detailed boundary plasma measurements of edge density, edge temperature, deuterium influx and carbon influx are reported from ohmically heated TFTR discharges over a range of plasma densities. The experimental results are compared with predictions from a simple zero-dimensional model based on power and particle balance. Reasonable agreement is obtained. More detailed impurity modelling is performed with the LIM impurity production and transport code. The complementary modelling approaches reveal, amongst other results, the important role of the sputtering yield at the limiter in determining the central effective charge of the discharge, the ability of a densified boundary plasma to screen impurities from the central plasma and the importance of cross-field particle transport to the TFTR limiter. The authors demonstrate that, under the conditions of this experiment, the behaviour of the boundary plasma and its effect on the central plasma appear to be explicable using rather simple considerations of power and particle balance
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.