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An experimental Lead Lithium (PbLi) loop named DRAGON-V has been built at the Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences (INEST, CAS). The purpose of this loop is to test the technical issues of PbLi blankets for fusion reactors, such as thermal hydraulics, material corrosion, magnetohydrodynamics (MHD) effect and safety issues, etc. The main heat recovery system of the DRAGON-V loop is the Concentric Recuperator Heat Exchanger (CRHE) which was made of T91 steel. It has counter flow arrangements with PbLi as the working fluid across the tube and shell sides. In this paper, the system was analyzed in detail for thermal performance, pressure drop, pumping power, entropy generation, the effect of inlet temperature of shell side fluid on overall performance, and the temperature distribution and flow characteristics. It was found that the effectiveness and heat transfer rate of the CRHE was decreased with the inlet temperature of the PbLi across the shell side. The difference of effectiveness calculated by correlation and simulation was about 4.5%. The high pumping power of PbLi fluid circulation was required on the shell side due to its thermo-physical properties variation, which resulted in the high pressure drop across the shell side as compared to the tube side. The temperature variation across the tube and shell sides indicated that the simulation results agreed well with the design parameters within a deviation of less than ˜ 5%.

The lead-based reactor is one of the key nuclear energy systems for Generation-IV (Gen-IV) and Accelerator Driven Subcritical Systems (ADS). The Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences (INEST, CAS) has taken significant initiative for the design and development of the China Lead-based Reactor (CLEAR) series since 2011. The conventional power generation system has low performance and optimization of main parameter is a challenge when power generation system is connected with lead-based reactor. A new/modified conceptual design of an efficient power generation system with two reheaters has been proposed on the basis of a 400 MWth (thermal power) lead-based reactor with high performance. The analysis results show that the thermal efficiency was influenced by number of reheaters (with bleed-off steam at different positions). The thermal efficiency of Schematic-III (with two reheaters) was 44.3% and higher than Schematic-I and II (one reheater with bleed-off steam from the supply line of the first regenerator and main supply line, respectively). However, key parameters of the power generation system have been optimized to increase the overall performance of Schematic-III. The optimized temperature of feed water at the inlet of the reactor was 360 °C with a flow rate of 237 kg·s−1 and the outlet temperature of the reactor was 558 °C. The efficiency and net power of the plant increased with the part load.

China's record in reducing poverty over the last three decades has been impressive, yet few studies have examined the incidence of poverty among older people despite the rapid ageing of the population. This article uses a unique national data set to examine patterns of poverty, deprivation and exclusion among the urban aged population (60 years and over) in 2000. The results point to the importance of poverty as an issue for older people, particularly for women and those who live alone. A number of indicators of hardship are developed in four areas – economic insecurity, housing, health, and social isolation – and the incidence of these is examined, separately and in combination, by living arrangement and gender. Women are shown to experience greater levels of hardship and isolation than men, and to be more likely to experience multiple deprivation across two or more areas. Finally, the overlap between poverty and hardship is examined as a way of validating the poverty estimates and giving them greater credibility. The results indicate that there are strong overlaps, although these differ across the different dimensions of hardship. Access to pension income and concern over the cost of necessary visits to see a doctor emerge as strong predictors of poverty and point to areas where policy change is needed.