中冷后回热式布雷顿-逆布雷顿联合循环性能优化"

Performance Optimization for Combined Intercooled Regenerative Brayton and Inverse Brayton Cycles with Regeneration After Inverse Cycle

对中冷后回热式布雷顿-逆布雷顿联合循环构型进行有限时间热力学分析和优化,推导出了燃料燃烧放热流率、循环净功率、循环热效率和各个部件由于流动不可逆性产生的压力损失与顶循环压气机进口相对压力损失的函数关系。给出了循环净功率的分析和优化结果,以及在燃油消耗和尺寸约束条件下循环热效率的分析和优化结果。通过数值计算,详细分析了各主要设计参数对循环最优性能的影响。研究发现,存在最佳的中冷压比、压气机1进口相对压力损失、压气机3的压比和总压比,使循环功率获得最优值;在燃油消耗和装置尺寸的约束下,存在最佳的中冷压比、压气机1进口相对压力损失和总压比,使循环效率获得最优值;中冷过程能有效提高循环的功率,回热对循环功率影响很小。

The finite time thermodynamic analysis and optimization were carried out for the combined intercooled regenerative Brayton and inverse Brayton cycles with regeneration after the inverse cycle. The analytical formulae about the heat-released rate produced by the burning fuel, the cycle power output, the cycle thermal efficiency and the pressure losses of components due to the flow irreversibility of the working fluid versus the compressor inlet relative pressure drop of the top cycle were derived. The analysis and optimization results of the cycle power output and the cycle thermal efficiency under the constraints of the fuel consumption and the plant size were provided. The effects of the main design parameters on the optimal performances of the cycles were analyzed by detailed numerical examples. The study found that the power output has a maximum with respect to the intercooling pressure ratios, the inlet relative pressure drops of compressor 1, the pressure ratios of compressor 3 and the total pressure ratios. With the constraints of a fixed fuel flow rate and the power plant size, the efficiency can be maximized with respect to the intercooling pressure ratios, the inlet relative pressure drops of compressor 1 and the total pressure ratios. The circulatory power can be effectively improved by the intercooling process while the impact from the regenerative process is little.