Analysis of ICRF ferrite tuner

This paper describes the analysis following the breakdown of an ICRF tuner purchased from AFT. The codes used in the analysis were CST and COMSOL. These codes use the standard gyromagnetic model for the ferrite which gives results that are largely in error when compared to measurements at ICRF and Lower Hybrid frequencies. We have measured a slab of the ferrite used in the ICRF tuner provided by AFT and from these measurements we have constructed a tabular model of the ferrite and inserted it into the COMSOL code. The results give performance which closely agrees with the performance specifications issued by AFT. We then used this modified code to correlate the simulation with the destructive evidence found in the tuner. The correlation was good between the destruction spot and the peak of the standing electric field. Pictures of the destruction and the heating in the tuner and the standing field results from the simulation will be given.