Thermodynamic optimization of design variables and heat exchangers layout in HRSGs for CCGT, using genetic algorithm

The heat recovery steam generator (HRSG) is one of the few equipments that are custom made for combined cycle power plants, and any change in its design affects all performance parameters of a steam cycle directly. Thus providing an optimization tool to optimize its design parameters and the layout of its heat exchangers is of great importance. A new method is introduced for modeling a steam cycle in advanced combined cycles by organizing non-linear equations and their simultaneous solutions by use of the hybrid Newton methods in this article. Thereafter, optimal thermodynamic performance conditions for HRSGs are calculated with the help of the genetic algorithm. In the conclusion, the results obtained for different types of HRSGs are compared. The results show that the use of several pressure levels in HRSGs increases the power production in the steam cycle, and similarly, reheating is very beneficial in three pressure heat recovery steam generators.