核能闭式循环氦气轮机动力装置性能优化

Performance Optimization for Closed-cycle Helium Turbine Nuclear Power Plant

以潜艇用高温气冷堆氦气轮机循环为对象 ,用有限时间热力学理论和方法优化其性能 ,导出循环的功率、功率密度 (功率与循环中最大比容之比 )和热效率表达式 ,在高、低温侧换热器和回热器总热导率一定的条件下优化三个换热器热导率分配 ,得最佳功率、功率密度和热效率 ,并与文献中的概念设计方案性能作了比较。

The performance of closed cycle helium turbine nuclear power plant for submarine propulsion is optimized in the viewpoint of finite time thermodynamics (FTT) or entropy generation minimization (EGM) in this paper. The power output, the power dinsity (ratio of power output to the maximum specific volume in the cycle) and the thermal efficiency of the cycle are derived. The model adopted is an irrevarsible regenerated closed Brayton cycle coupled to variable temperature heat reservoirs. In the analysis, the heat resistance losses in the hot side heat exchanger (intermediate heat exchanger) and cold side heat exchanger (precooler) and the recuperator, the irreversible compression and expansion losses in the compressor and turbine, the pressure drop losses at the heater, cooler and recuperator as well as in the piping, and the effect of the finite thermal capacity rate of the heat reservoirs are taken into account. The maximum power, the maximum power dinsity and the maximum efficiency are obtained by searching the optimum heat conductance distribution among the hot and cold side heat exchangers and the recuperator for the fixed total heat exchanger inventory with respect to the corresponding optimization objectives. The optimum results are compared with those reported in recent references for the conceptual design of a closed cycle helium turbine nuclear power plant for submarine propulsion. The numerical example shows that the method herein is valid and effective. The theory, the method and the results herein may provide guidance for the performance improvement and optimum design of real closed cycle helium turbine nuclear power plant.