The Performance Modelling of a Single and Dual Pressure Unfired Once Through Steam Generator

During the worldwide combined cycle power plant (CCPP) power plant building boom high pressure steam cycle has been the design of choice for the most power plant developers. In combined cycle power plant; there are many key areas that can be focused on for improving the thermal efficiency of the cycle and their performances. One of these areas is the unfired heat recovery steam generator so-called once through steam generator (OTSG). The unfired utility scale OTSG is a critical component in the combined cycle power plant, since it is the connection between the gas turbine (GT) and the steam turbine (ST) power units. In this paper, an adequate model has been developed for performance simulation of the once through steam generator OTSG in CCPP application. This model is well applicable for single and two-level of the steam cycle operation pressure. The developed model was tested against an existing OTSG installed at Manx Electricity Authority, and the obtained results and conclusions from this effort are satisfactory with a neglected error and will be a magnificent starting point for future improvements.