Author(s)

André Felippe Vieira Da Cunha¹, Naum Fraidenraich¹, Leomi De Souza Silva²

¹Department of Nuclear Energy, Federal University of Pernambuco (UFPE), Recife, Brazil.
²Department of Mechanical Engineering, Federal University of Pernambuco (UFPE), Recife, Brazil.

The optimum efficiency and net work of the regenerative cycle with turbine extractions, using steam as the working fluid, have been simulated and analyzed. The cycle is simulated with until five feed water heaters in a numeric method and can be easily used in solar power plants. The general expression for each component is realized through the balance of energy, collectors, turbine, condenser, pumps and feed water heaters. One analytical method is developed considering constants of the difference of enthalpy through feed water heaters as also between them. The results show that the analytical method is unsatisfactory because the optimum efficiency depends on some parameters such as evaporating temperature and superheating temperature showing in numeric method. The increase of optimum efficiency increases when the number of feed water is increased as well as evaporating and superheating temperature, for the net work presents a maximum value along evaporating temperature, decreasing with number of feed water heaters and increasing when the superheating temperature is increased. The pressure of extraction of turbine is also analyzed, varying about 5% along of evaporation temperature. This analysis is important to motivate the use in solar plants that it is considerate in this paper, just analyzing the cycle.

Regenerative Cycle, Thermal Cycle, Thermodynamics

Da Cunha, A. , Fraidenraich, N. and Silva, L. (2017) Optimum Efficiency Analysis of Regenerative Cycle with Feed Water Heaters. Journal of Power and Energy Engineering, 5, 45-55. doi: 10.4236/jpee.2017.58004.