Fast Simulation of Local Radiation Fields for Synthetic Diagnostics

摘要

Introduction The development and validation of algorithms for plasma control in tokamaks requires the simulation of the dynamic signals from plasma diagnostics. A Synthetic Diagnostic (SD) is a computational module which simulates the measurements made by a diagnostic as well as the signals sent over the real-time network used for control. The computed signals should be sufficiently realistic to be applied for plasma discharge scenario planning and analysis. Typically, simulation of the signals requires the use of resource-intensive Monte-Carlo or raytracing codes using detailed 3D models which take many hours of CPU time for a single time slice making simulations of evolving plasma unacceptably long and expensive. For the cases when the impact of the sources on the diagnostic signal is additive over the spatial distribution, it is possible to use an approach based upon Green's functions. We describe a technique based on this concept. The technique is applicable to dynamic simulations of diagnostic signals for a range of neutron and optical diagnostics in tokamak plasmas. Here we describe the method applied to the Divertor Neutron Flux Monitor (DNFM) [1] SD as an example.