[en] The results of tests on a 1/10 scale model PCRV in the elastic range, in the cracked condition and in the ultimate loading condition is presented. The linear and non-linear stress analyses and ultimate load assessment of the model are also presented. In the linear analysis, three-dimensional finite element methods with arbitrary arranging nodes were used, and in the non-linear analysis, three-dimensional (axisymmetric) finite element methods were used. The interaction of liner, prestressing cable, rebar and concrete solid were considered in both analyses. The ultimate load of the PCRV was calculated by using the yield line method. There was generally good agreement between the test results and theoretical predictions. (author)

[en] Highlights: • A theoretical model considering thermal model, energy model and weight/lift equilibrium was proposed. • The theoretical model was proved to be feasible through comparative analysis. • The effects of connection length, balloon diameter and ξ on the solar array output performance were studied. • Increasing the value of ξ is benefit to improve total output power of solar array until it reaches 1.5. Solar array plays a decisive role in the energy system of stratospheric balloon. Optimizing the layout of solar array is beneficial to the improvement of energy production, but the research about this subject is rare. This paper established a theoretical model consisting of thermal and energy model, weight/lift equilibrium. A MATLAB computer program is developed to simulate the output power of solar array and the energy harvesting along with connection length and balloon diameter. Through comparative analysis, the theoretical model is proved to be feasible. Further, the effects of connection length, balloon diameter and the ratio of connection length to balloon diameter are discussed in detail. The results show that solar array total output power is sensitive to the variation of the connection length, balloon diameter and the ratio of connection length to balloon diameter. Moreover, the layout of solar array can be optimized though increasing the ratio of connection length to balloon diameter, however, the total output power would not increase when the ratio of connection length to balloon diameter is greater than 1.5. Therefore, Choosing the proper ratio of connection length to balloon diameter might be an effective approach for optimizing the stratospheric balloon energy system.

[en] This paper describes the state-of-the art of the research work on the mainland of China pertaining to the prestressed concrete reactor vessel and to nuclear reactor containment. The results of tests of 1/10th scale model of a PCRV and its deep end slab are presented. The 3D linear and nonlinear stress analyses and ultimate load of these models are also described. A new type of containment, a steel-plate-concrete composite containment, is proposed and evaluated. At last, a survey of the Quin Shan Nuclear Power Plant is described. (orig.)

[en] Highlights: • The sealing performance of the composite B shape ring was analyzed for a high pressure polythene polymerizer. • The nonmetallic ring material Valqua 6502 was aged under 270 °C for 60 days, and compression and resilience tests revealed that its deformation ability was reduced due to aging. • For the high pressure polythene polymerizer, the sealing performance of the composite B shape ring is affect by the aging of the nonmetallic ring but together with the match of interference fit of the nonmetallic ring and clearance fit of the metal ring. • Optimal match of the interference and clearance fit was found for more advanced material XX300 but failed for 6502. B shape ring with metal and nonmetallic materials is often used in the high-pressure polythene polymerizer for the self-energized seal. However, many factories reported that leakages often occurred when pressure is lower than 30 MPa, especially during the shutdown after a long period of operation. In this paper, the nonmetallic material Valqua 6502 were aged at 270 °C for 60 days, which is close to the working conditions of polymerizer. The compression and resilience abilities were tested and compared with those before aging. It reveals that the temperature aging reduces both compression and resilience abilities of the nonmetallic materials. FEM model was worked out for the simulation of sealing performance, which includes working conditions such as the assembly of the self-energized structure, the start up with temperature and pressure rise and the shutdown with temperature and pressure drop. It reveals that the sealing performance is not only influenced by the aging of nonmetallic ring, but also related with the interference fit to nonmetallic ring and clearance fit to the metal ring. Another kind of nonmetallic material XX300 was also aged as comparison, which performed better than the currently used one. With parameter studies, optimal interference and clearance fit were worked out for XX300 but failed for 6502. Therefore, when B shape ring with nonmetallic and metal materials works under high temperature and high pressure, the aging of the nonmetallic material should be considered to avoid decreasing its deformation and resilience ability and harming the sealing performance.