COMPARISON OF MEASURED JET DIVERTOR PERFORMANCE WITH EDGE MODELS

A comparison is presented between a 1D SOL/divertor model (EDGE1D) and results from a set of L mode, low power NI heated single null divertor experiments run on the Be target plates. Two gas puff scans were run, one with outer midplane puffing, and the other with divertor puffing. Divertor and SOL parameters were measured with Langmuir probes and a CCD camera. Very good agreement and consistency were found between measurements in the SOL, outer divertor, inner divertor, and the code predictions, for the deuterium plasma, when the code predictions of electron pressure ratio between outer divertor and SOL were used to help determine the precise location of the reciprocating probe relative to the separatrix. Such features as inner-outer divertor asymmetries, parallel temperature gradients, and Be influx from the targets were all correctly modelled, within the error bars, and detached plasmas were observed both experimentally and numerically. However, the Be content of the SOL appears to scale differently than predicted.