Generalized Thermodynamic Analysis of Steam Power Cycles with ‘n’ Number of Feedwater Heaters

Abstract

Thermodynamic analysis has been carried out to analyze the effect of ‘n’ feedwater heaters (fwhs) on performance of a steam power cycle with a generalized mathematical formulation. The performance calculations are formulated separately to single fwh and extended to ‘n’ fwhs for parametric study. The optimum bled steam temperature ratio is found at 0.4 with single fwh at given working conditions. Similarly the optimum pressure in a steam reheater is obtained at 20-25% of the boiler pressure irrespective of the number of heaters. The results show that the maximum gain in the efficiency of cycle is obtained with the first fwh and the increment diminishes with the addition of the number of heaters. This work examined the improvements in efficiency with increases in boiler pressure, turbine inlet temperature and furnace temperature.

Keywords

• energy, exergy, feedwater heaters, generalisation, Rankine cycle