Identification of space and time varying thermal resistance: Numerical feasibility for plasma facing materials

AbstractThe present paper deals with a non-linear unsteady calculation combined with the conjugate gradient method (CGM) and the adjoint state, in order to characterize in-situ the spatial and time variation of the thermal resistance of a surface layer. This paper presents the numerical feasibility of this method for the plasma-facing components (PFC), and precisely on the surface carbon layer (SCL), usually poorly attached to the PFC in the fusion machines, a realistic experiment design was used. The accuracy of the method is examined by using simulated inexact infrared measurements obtained on the SCL surface. The advantages of applying the CGM with the adjoint state in the present study, are that no prior information is needed on the time variation and for the initial guesses of the unknown thermal resistance.