tailieunhanh - Advanced Gas Turbine Cycles phần 6

Các mô phỏng thứ hai với mô hình đầu tiên đã được thực hiện đối với trường hợp lý tưởng, có nghĩa là không có thiệt hại được xem xét trong các máy nén, trao đổi nhiệt, buồng đốt cháy và giãn nở. Trong so với 1a mô hình các giá trị của tất cả các hiệu quả trong vòng 10% trường hợp cao hơn, đó là một kết quả rõ ràng bỏ qua những tổn thất. | Study of the thermodynamic cycle with GateCycle 44 Model 1b - no losses The second simulation with the first model was made for the ideal case which means that no losses were considered in the compressors the heat exchanger the combustion chamber and the expander. In comparison to the model 1a the values of all the efficiencies are in this case round 10 higher which is an obvious result of neglecting the losses. The graphs have no local maxima. Thermal efficiency is increasing for an increasing nT and decreasing nLPC till it reaches 100 . On the contrary to the model 1a the biggest value of nh happens for nLPC 1. When the value d increases the highest efficiencies are slightly decreasing and the smallest increasing. Study of the thermodynamic cycle with GateCycle 45 nth nT T1LFO1 T1LRC2 T1LFFC25 T1LFFC3 T1LFFC5 T1LFO1Q T1LFO15 T1LFO2Q T1LFO25 T1LFO3Q T1LFO35 T1LFO42 tiUFOttT Figure 30 GateCycle Results - thermal efficiency nT nLPC 0 4 kcc 1 kic 1 npt 100 npc 100 nLFO 1 nLFO 2 nLFO 25 nLFO 3 nLFO 5 nLFO 1Q nLFO 15 nLFO 2Q nLFO 25 nLFO 3Q nLFO 35 nLFO 42 nlJOrfr nT Figure 31 GateCycle Results - thermal efficiency nT nLPC 0 5 kcc 1 kic 1 npt 100 npc 100 nT Figure 32 GateCycle Results - thermal efficiency nT nLPC 0 kcc 1 kic 1 npt 100 npc 100 Study of the thermodynamic cycle with GateCycle 46 Model 1c - higher than ambient temperature heat exchanger outlet temperature Since the real conditions are unknown and the assumption made in the beginning that the heat exchanger cools the flow to the ambient temperature could be not true. It was sensible to check what happens in that case. The dTIC 40K is an arbitrary value. The study is being conducted to show the behavior of the thermodynamic cycle under such a condition. From the results which are presented on figures 33-35 it can be concluded that the characteristics are similar as in the case of 1a. However the efficiencies are smaller by 1 to 2 . The trend that the efficiencies are the highest for low values of nLPC .