Studies On The Stability Of Wet Compression Gas Turbine System

From the scope of thermodynamics, wet compression technique can effectively act as an inlet-cooling method, improve the output of the turbine and then enhance the performance of the whole system. Meanwhile, wet compression technique is able to reduce concentration of harmful exhaust such as NO_x etc for the environment. And here we concern its influence toward compression system's instabilities-rotating stall and surge. Such research should be a new topic to the field of wet compression technique and compressor stability.Two types of aerodynamic flow instabilities can be encountered in the compressors: rotating stall and surge, which are key and difficult problems in development and design of compressors. Lots of theoretic and experimental work had been done in this field in our country and overseas. There are several major aspects of analysis and research work done in this dissertation which list as following: 1) deducing the wet compression Moore-Greitzer model; 2) adding the mass and momentum influence of spaying water to the compression system in order to amend the fore model; 3) using MATLAB to simulate the revised wet compression Moore-Greitzer model; 4) analyzing different cases of parameter-B in various contents of water; 5) bringing forward the active control method of wet compression to control rotating stall and surge in compressors; 6) linearizing the wet compression Moore-Greitzer model, analyzing the model with bifurcation theory and hence using eigenvalues of its coefficient matrix to judge stability of the compression system and so on.Here in this dissertation the results of MATLAB simulation and numeric analysis may demonstrate that at first wet compression technique theoretically might not worsen the stability of the compression system and further might improve and even avoid the instabilities of stall and surge; and that there would be a critical parameter-B and different demand of water for differently setting basicparameters of compressors; and that wet compression can be used as a new method of active control to control the instabilities of compressors; and that both active control actuators of wet compression and valve can effectively control rotating stall and surge.