L Giancarli et al Fusion Engineering and Design 61-62(2002)307-318 Table 2 The obtained maximum stresses largely satisfy Design point for a typical blanket module of the TAURO the TaURo criteria in the whole sub-module reference design structure including the first wall: its maximum Module height 2 m value of 0.75 is reached in the composite plane Module width 0.3m which indicates reasonable design margins FW thickness For the tauro blanket both core sector Thickness first Pb-17Li channel Surface heat flux on Fw 0.5 MIm maintenance or core segment maintenance are Neutron wall loading on Fw 2.5 MW/m possible. In fact, the choice of maintenance Maximum Pb-17Li velocity procedure depends on many other considera- Pb-17Li inlet/outlet temperatures 800°C tions concerning the whole reactor plant; there- AT through Fw fore, this item has not yet been addressed aximum Temperature in SiCf/SiC However, a reactor study involving SCLL Maximum pb-I7Li-SiCiSiC interface tem. 915 blanket is being performed in 2002 within perature in the first channel the eu. and more information on blanket integration within the reactor will be available The MhD pressure drops are maintained at formed in 3D, assuming square meshes and an olerable levels by the relatively low electrical orthotropic model for SiCH/SiC. Due account was conductivity of SiC compared to steel in spite of taken of the poloidal variation in heat transfer coolant conditions. mechanical loads and thermal the relatively high velocity of the flowing Pb 17Li. loads. Conduction through Pb-I7Li has been considered as the dominant and therefore unique heat transfer mechanism. Assumed Sic/SiC prop- erties and parameters are those given in Table 1. 3.2. 4. Manufacturing and mounting scheme The TaURO design criteria [12] have been applied The different basic mponents have with limits described hereafter manufactured and then assembled separately The manufacturing of the module depends on Tensile and compressive stresses in plane are the possibility of joining SiC/SiC components. In limited to 145 and 580 MPa, respectively; order to be efficient, joining techniques require a Tensile and compressive stresses through the relatively large contact region between the differ hickness are limited to 110 and 420 MPa ent sub-components. Different joining techniques respectively; and can Shear stresses through the thickness are limited be envisaged: (i)assembling by sewing at 0 45 MPa textile stage to join the stiffeners to the side walls (ii) sticking and co-infiltration to join the second 3.2.3. Performances and modeling wall to the first stiffener; (iii) brazing of finished components n the bottom and the top closure Some of the main design features and perfor mance parameters of the reference design are plates and the different sub modules Therefore the stiffeners could be manufactured highlighted below with a T shape or an L shape surface at the end. A 3D neutronics analysis yields a tritium- The proposed fabrication scheme needs 10 coolant breeding ratio of 1.1 containment brazes per sub-module. For a module Assuming laminar Pb-17Li flow and neglecting consisting of 5 sub-modules this corresponds to onvection, the maximum SiC temperature at braze length of about 20 m(not including the top the first wall is 995C, and the maximum SiC/ and bottom caps) Pb-17Li interface temperature at the inner The fabrication scheme of a sub-module could channel wall is9l5° be the one illustrated in Fig. 4 where the differentformed in 3D, assuming square meshes and an orthotropic model for SiCf/SiC. Due account was taken of the poloidal variation in heat transfer, coolant conditions, mechanical loads and thermal loads. Conduction through Pb/17Li has been considered as the dominant and therefore unique heat transfer mechanism. Assumed SiCf/SiC prop￾erties and parameters are those given in Table 1. The TAURO design criteria [12] have been applied with limits described hereafter: . Tensile and compressive stresses in plane are limited to 145 and 580 MPa, respectively; . Tensile and compressive stresses through the thickness are limited to 110 and 420 MPa, respectively; and . Shear stresses through the thickness are limited to 45 MPa. 3.2.3. Performances and modeling Some of the main design features and perfor￾mance parameters of the reference design are highlighted below: . A 3D neutronics analysis yields a tritium￾breeding ratio of 1.1. . Assuming laminar Pb/17Li flow and neglecting convection, the maximum SiC temperature at the first wall is 995 8C, and the maximum SiC/ Pb/17Li interface temperature at the inner channel wall is 915 8C. . The obtained maximum stresses largely satisfy the TAURO criteria in the whole sub-module structure including the first wall; its maximum value of 0.75 is reached in the composite plane which indicates reasonable design margins. . For the TAURO blanket, both core sector maintenance or core segment maintenance are possible. In fact, the choice of maintenance procedure depends on many other considera￾tions concerning the whole reactor plant; there￾fore, this item has not yet been addressed. However, a reactor study involving SCLL blanket is being performed in 2002 within the EU, and more information on blanket integration within the reactor will be available soon. . The MHD pressure drops are maintained at tolerable levels by the relatively low electrical conductivity of SiC compared to steel in spite of the relatively high velocity of the flowing Pb/ 17Li. 3.2.4. Manufacturing and mounting scheme The different basic components have to be manufactured and then assembled separately. The manufacturing of the module depends on the possibility of joining SiCf/SiC components. In order to be efficient, joining techniques require a relatively large contact region between the differ￾ent sub-components. Different joining techniques can be envisaged: (i) assembling by sewing at textile stage to join the stiffeners to the side walls; (ii) sticking and co-infiltration to join the second wall to the first stiffener; (iii) brazing of finished components to join the bottom and the top closure plates and the different sub modules. Therefore, the stiffeners could be manufactured with a T shape or an L shape surface at the end. The proposed fabrication scheme needs 10 coolant containment brazes per sub-module. For a module consisting of 5 sub-modules this corresponds to a braze length of about 20 m (not including the top and bottom caps). The fabrication scheme of a sub-module could be the one illustrated in Fig. 4 where the different Table 2 Design point for a typical blanket module of the TAURO reference design Module height 2 m Module width 0.3 m FW thickness 3 mm Thickness first Pb/17Li channel 8.5 mm Surface heat flux on FW 0.5 MW/m2 Neutron wall loading on FW 2.5 MW/m2 Maximum Pb/17Li velocity 2.25 m/s Pb/17Li inlet/outlet temperatures 800 8C/ 957 8C DT through FW 115 8C Maximum Temperature in SiCf/SiC 995 8C Maximum Pb/17Li/SiCf/SiC interface tem￾perature in the first channel 915 8C L. Giancarli et al. / Fusion Engineering and Design 61/62 (2002) 307/318 313