The distribution of exergy destruction is different in power plant systems with water cooled condenser and air cooled condenser. A detailed comparison based on a conventional Rankine cycle with two different cooling configurations is carried out in this paper in an exergy perspective. The inefficiency of the overall systems is analyzed in the same amount of heat transfer capacity condition, it shows that the distribution of exergy destruction among components is similar in both conditions. And this study of energy consumption is benefit for realization of auto-efficient-working power plants in future.

This paper takes G4-73 centrifugal fan as the reference model. A practical parametric software platform was developed with VB Programming languages and Fluent software. Numerical simulation based on k-e turbulence model in the same flow rate was taken using the platform. The results show that the total pressure and efficiency of fans will be ideal when the blade angle take 45 degree, which is the design value. However, the best impeller width gotten from numerical simulation is smaller than the design value, that is, 18.5 cm is the most suitable value. The conclusion is of great significance for the subsequent optimization and reconstruction of fan.

The exhaust pressure affects the economic performance of the whole power unit greatly. Based on the theory of energy specific fuel consumption (ESFC), the changing principle of energy consumption in a power unit was studied. In the turbine unit, the energy-consumption caused by topological factors was also discussed with different exhaust pressure. The results showed that the changing of exhaust pressure makes great effects on topological energy consumption of steam turbine. It makes great reference for the energy-saving diagnosis of the energy consumption for the overall power units.