Speaker
Dr
Antonio Pimazzoni
(Consorzio RFX)
Description
In order to verify the accomplishment of the ITER requirements regarding the maximum allowed beam non-uniformity (below ±10%), beamlet divergence and stripping losses during short pulse operation (several seconds), a diagnostic calorimeter, named STRIKE [1], will be exposed to the negative hydrogen ion beam of the ITER ion source prototype SPIDER [2]. The facility, located at Consorrzio RFX (Padova, Italy) has started the experimental activities in 2018 at Consorzio RFX (Padova, Italy).
The STRIKE sensor is constituted by 16 unidirectional carbon fiber-carbon matrix (CFC) composite tiles (376 mm × 142 mm × 20 mm), arranged in a 4 × 4 matrix, resembling the arrangement of the SPIDER beamlet groups. By exposing the tiles to the beam and recording their temperature with infra-red cameras the beam energy flux can be retrieved by calorimetry.
The requirements of the 1D CFC material include a large thermal conductivity along the tile thickness (one order of magnitude larger than in the other two directions), uniform parameters over the tile surface and the capability to withstand localised heat loads in the order of 10-20 MW/m2.
The realization of large CFC tiles satisfying all of these requirements is not straightforward and tests were performed in the last years on many prototype versions from different manufacturers. This contribution gives an overview of the tests performed to assess the thermal properties of the tiles composing the actual STRIKE, to be installed in the SPIDER vacuum vessel during 2018. The spatial uniformity of the parameters and the ratio between the thermal conductivities are assessed by means of a CO2 power laser at Consorzio RFX. Non-linear thermal finite-element simulations are carried out and compared to the experimental data to interpret them and to estimate the thermal conductivities.
This work was set up with partial financial support of F4E.
[1] A. Rizzolo et al., Fusion Eng. Des. 85, 2268 (2010)
[2] R.S.Hemsworth et al., Rev.Sci.Instrum. 79 (2008) 02C109
Primary author
Dr
Antonio Pimazzoni
(Consorzio RFX)
Co-authors
Mr
Daniele Fasolo
(Consorzio RFX)
Dr
Gianluigi Serianni
(Consorzio RFX)
Mr
Luca Franchin
(Consorzio RFX)
Mr
Marco Tollin
(Consorzio RFX)
Dr
Mauro Dalla Palma
(Consorzio RFX)
Dr
Roberto Pasqualotto
(Consorzio RFX)
