Three-dimensional thermal and structural analysis of the first wall in the SIRIUS-P reactor
The thermal-structural behavior and performance of the SIRIUS-P power reactor first wall concept is analyzed. The SIRIUS-P conceptual design study is of a 1.0 GWe laser driven inertial confinement fusion power reactor utilizing near symmetric illumination of direct drive targets. Sixty laser beams providing a total of 3.4 MJ of energy are used at a repetition rate of 6.7 Hz with a nominal target gain of 118. The spherical chamber has an internal radius of 6.5 m and consists of a first wall assembly made from carbon-carbon composite material, and a blanket assembly made of SiC composite material. The chamber is cooled by a flowing granular bed of solid ceramic materials, non-breeding TiO{sub 2} for the first wall assembly and breeding Li{sub 2}O for the blanket assembly. Helium gas (P = 0.15 MPa) is used in a fluidized bed outside the reactor to return the particles to the top of the reactor. A moving bed is chosen over a fluidized bed because of its superior heat transfer capability. The heat transfer in a moving bed depends on the level of agitation and on the effective thermal conductivity of the solid material and the interstitial gas, whereas in a fluidized bed,more » it is entirely dominated by the thermal conductivity of the carrier gas. This work describes the three-dimensional thermo-structural steady state analysis of the first wall coolant tubes. The performance of the first wall depends, under normal operating conditions, on the thermal loading conditions and internal coolant pressure loading conditions. The analysis utilizes a commercial finite element analysis code with complete 3-D modeling. The analysis shows that the stresses are dominated by bending due to the internal pressure of the He gas; modifying the shape of the tube from purely elliptical at the midplane, while keeping the flow area constant, reduces the stresses. A comparison between the results of this 3-D model with a previous 2-D study shows a pronounced effect on the temperature distribution.« less
Composite materials for fusion applications
Ceramic matrix composites, CMCs, are being considered for advanced first wall and blanket structural applications because of their high-temperature properties, low neutron activation, low density and low coefficient of expansion coupled with good thermal conductivity and corrosion behavior. This paper presents a review and analysis of the hermetic, thermal conductivity, corrosion, crack growth and radiation damage properties of CMCs.
On the Role of Professional Sports in the National Economy Under the Market Economy Conditions
Through the research of the present situations of the professional sports at home and abroad and its influence on economy, this paper points out the opportunities, challenges and the exist- ing main problems that the professional sports faces in the transitional peried-from plan economy to market economy, then elucidates that the professional sports can becompletely developed and improved and play an important role in the national economy under the market economy conditions.