In view of the problems of small available temperature difference and low utilization efficiency of ocean thermal energy conversion (OTEC). A new thermodynamic cycle of OTEC using non-azeotropic mixed working fluid is proposed. Based on the laws of thermodynamics, the thermodynamic analysis of the proposed thermodynamic cycle is carried out. Evaporation pressure, mass fraction of working fluid, evaporation temperature and condensation temperature are selected as influencing variables to study the proposed thermodynamic cycle. The results show that when the working fluid mass fraction is selected as a variable, with the evaporation pressure increases the cycle thermal efficiency and the net output of system increase first and then decrease. The system thermal efficiency achieves a maximum value of 5.28% when the working fluid mass fraction is 0.91. The maximum value of 3.83 kW is obtained when the mass fraction of the working fluid is 0.96. When the evaporation pressure is selected as the variable, the cycle thermal efficiency and the net output of the system increase first and then decrease with the mass fraction of the working medium increases. The cycle thermal efficiency achieves a maximum value of 5.26% when the evaporating pressure is 0.595 MPa, and the net output work obtains a maximum value of 3.57 kW when the evaporating pressure is 0.58 MPa. Compared with Uehara cycle and Yoon cycle under the same operating conditions, the proposed cycle system has the highest thermal efficiency. The analysis results of the proposed thermal cycle system can provide a theoretical basis and reference for improving the utilization efficiency of OTEC.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |