The Simulation Study Of Performance On The Marine Gas-steam Combined Power Systems

Gas turbines are widely used on ships around the world. Improving the economics of gas turbine power plants has also been paid more and more attention. Combined Gas and Steam Cycle (COGAS) is one of the effective ways.Gas-steam combined cycles have been applied on ships in foreign countries. However, this technology has not been applied in the ships in China, which only applied in the power plant. So researches on gas-steam combined cycles are very meaningful for the development of China's shipbuilding.This dissertation analyzes the two common types of combined cycle. The factors of waste heat boiler fuel supplement, waste heat boiler water cycle, and steam cycle mode of the system are considered to determine the waste heat boiler schemes in this dissertation. After the schemes are established, according to the selected principle of the main parameters and optimization principles, the parameters of the waste heat boiler are determined. According to the selected parameters, thermal calculations and smoke resistance calculation of waste heat boiler are worked out, and the parameters of the inlet and outlet of steam turbine are determined. On the basis of the steam determined system's schemes,the feasibility of the gas-steam combined cycle's scheme in the ship is conducted.The dynamic mathematical models of the gas turbine, waste heat boiler and steam turbine are established. Then according to mathematical models, simulation models of the components are established on the Matlab / Simulink simulation platform. According to the relationship among these components, the gas-steam combined cycle simulation model of the entire system is completed. With the simulation model, based on changes in gas turbine loads, gas-steam combined cycle's steady-state performance and variable working performance are studied. This is to confirme that the simulation model is reasonable.At last, with gas turbine load changes and changes in the amount of fuel, dynamic performance of the combined-cycle is studied.This provides certain theoretical basis for the application of gas-steam combined cycle in the ships in our country.