COMPUTER-SIMULATION OF A COMBINED-CYCLE POWER-PLANT

This paper presents the simulation procedure developed to predict the performance of a combined cycle power plant from given performance cha racteristics of its main components. In order that the procedure could be validated, the simulation technique has been applied to a typical combined cycle power plant (having a dual pressure bottoming cycle) ma nufactured by a prominent company. The characteristics of the standard equipment like the air compressor, steam and gas turbines, various pu mps, etc. have been taken from the manufacturer's catalogues and conve rted into appropriate equations based on theoretical understanding. Th e performance of various heat exchangers (like economizers, superheate rs, evaporators, etc.) has been determined by using the effectiveness concept after evaluating the overall heat transfer coefficient by usin g appropriate correlations from literature. The strategy of system sim ulation is obtained by judiciously interlinking the information flow d iagrams of various components and thus the task is finally reduced to that of solving nine non-linear equations for nine variables. The pred icted performance of the system is seen to be in good agreement with i ts rated performance.