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This paper aims to provide a comprehensiveness description of the ITER Thermal Shield thermal integrity management keeping focused on the methods required for supporting the Thermal Shield manufacturing and assembly phases. Three main aspects are covered: 1) accurate heat load estimation into the Thermal Shield; 2) thermo-hydraulic flow modelling; 3) combined analytical-experimental method for sizing pipe orifices. The Thermal Shield heat loads estimation has to be accurate in order to know the margins regarding the agreed limits with the Cryoplant and Magnets. The proposed methodology results on a better understanding of the level of conservatism of the estimated heat inputs into the Thermal Shield. A detailed analysis of the coolant temperature rise on the cooling tubes is also described in combination with experimental data and fluid-dynamic analysis of the required pipe orifices. As a result, a pipe orifices sizing method is described and it is assessed the convenience of introducing thermo-hydraulic considerations into the flow analysis. As conclusion the paper presents the whole strategy as a powerful tool for properly assessing the impact of the silver coating quality (during manufacturing and assembly) as well as the impact of the final design of the interfacing systems and the actual final flow.

Flow distribution on the piping network of ITER Thermal Shield (TS) is analyzed and orifice installation is suggested for attenuating flow mal-distribution. Flow test is performed for a TS segment to verify the analysis model. Room temperature nitrogen gas passes through the cooling pipe on TS segment with test flow rate which is equivalent to the actual operating condition of TS. Flow rate is controlled by a thermal mass flow controller and pressure drop between the inlet and the outlet of the pipe routing is measured by a differential pressure gauge. Test result is compared with the analysis one to check the validity of the analysis model for the real manufactured TS segment. The flow test is also conducted for the fabricated orifices. The loss coefficient of the orifice is compared with that used in the analysis. The loss coefficient correlation for the fabricated orifices is obtained from the test results.

Purpose The aim of this study was to assess accuracy, consistency and performance time of the kick(front kick, side kick) of elite Poomsae players who accustomed excessive high kick. Methods Accuracy, consistency and performance time were measured by 3D motion capture system. Twelve elite Poomsae players(age: 28.83±1.80 yrs, height: 171.75±4.29 cm, weight: 67.58±3.6 kg) performed Poomsae kick according to the four target(philtrum, solar plexus, hypogastric, knee) and target or non-target. Results 1) Both of Front kick and Side kick were evaluated highest accuracy and consistency at philtrum. 2) Both of Front kick and Side kick were tend to increase on accuracy and consistency as the target height increasing. 3) The accuracy of Front kick and Side kick was decreased when the target is not provided at hypogastric and solar plexus. 4) There were statistically significant differences in performance time according to the height of four targets on Side kick but no differences on Front kick in performance time. Conclusion Overall elite Poomsae players who are familiar with kicking in high target were assessed poor kicking performance on lower target.

This paper describes both the test results of the bath type silver coating and the design of the bath to construct the silver coating plant for ITER thermal shield. The tests of small specimens made of SS304L and SS304LN were carried out to investigate the effect of the nitrogen content in SS304LN on the silver coating quality. The effect of different degreasing agents was also investigated to improve silver coating process. Small mock-up was tested to find a proper dipping direction during the electroplating process. Finally, noble bath design was conceived and structurally validated. Overall layout of silver coating plant is also shown in this paper.

The ITER thermal shield is actively cooled by 80 K pressurized helium gas. The helium coolant flows from the cold valve box to the cooling tubes on the TS panels via manifold piping. This paper describes the final design of thermal shield manifold. Pipe design to accommodate the thermal contraction considering interface with adjacent components and detailed design of support structure are presented. R&D for the pipe branch connection is carried out to find a feasible manufacturing method. Global structural behavior and structural integrity of the manifold including pipe supports are investigated by a finite element analysis based on ASME B31.3 code. Flow analyses are performed to check the flow distribution.

Thermal shield (TS) is to be installed in ITER tokamak to minimize radiation heat load transferring from the vacuum vessel and the cryostat to the superconducting magnet operating at 4.5 K. The TS shall be properly designed so that the radiation heat load is below the specified requirement for the magnet. This paper describes how the ITER TS is modeled to verify its thermal performance. The 3D finite element (FE) models of repetitive sections of the whole TS were developed in this study. The major geometric simplifications applied to the FE models are illustrated. Passively cooled removable panel on the cryostat TS (CTS) for the in-cryostat maintenance of the magnet was modeled considering thermal contact at the joint. The boundary temperature of the CTS support was determined from the analysis of cryostat with the TS. Total heat load from the TS to the magnet was evaluated for the steady state of plasma operation. Cool-down behavior of the TS was also investigated by the transient analysis of the representative models. The maximum panel temperature and the helium outlet temperature were obtained during cool-down of TS.

Recent progress of the ITER thermal shields (TS) design is presented. As the ITER construction phase approaches, the design of the TS has been improved and developed in more detail with the focus on better performance, improved manufacture ability and successful assembly at the ITER-site. Aiming at the supply of the TS components to the ITER-site, the Procurement Arrangement with the Korean Domestic Agency (KO DA) was signed. In cooperation with the Korean industry, a preliminary study of the TS manufacture was performed – accompanied with several R&D activities (including manufacture of a full-size mock-up of the TS panel). Results of all above activities are described in this paper.