Design And Numerical Simulation Of Gas Turbine Inlet Spray Cooling

The power generation efficiency of gas-steam combined cycle is closely related to the inlet air temperature,when the inlet air temperature increases,the air density becomes smaller,air mass flowing into the compressor and gas turbine reduces,reducing the efficiency of the gas turbine;The increase of inlet air temperature reduces the compression ratio of the compressor and the output power of the gas turbine.Meanwhile,the power consumption of the compressor increase,which further reduces the output of the gas turbine.Reduction of exhaust gas from the combustion engine reduces the efficiency of the waste heat boiler,thus reducing the turbine efficiency.Reducing the inlet air temperature of the unit is the most useful way to increase its power generation efficiency.Spray evaporation cooling is to install a certain number of nozzles into the gas turbine pipeline inlet,atomizing the desalted water,increasing the contact area between water and air,thereby accelerating the evaporation of the desalted water,reducing the temperature of the inlet air of the compressor.The inlet air cooling method has the advantages of less investment,low operating costs,and easy operation and maintenance.By studying the basic theory of humidification cooling and using MATLAB to write the humidification cooling program for calculation and analysis,the spray cooling effect data under different initial air conditions is obtained and the relationship between the various parameters is drew.These figures clearly indicate that the higher the initial inlet temperature and the lower the relative humidity,the better the spray cooling effect is,the greater the amount of water is required to spray.Spray evaporati on cooling is best suited for hot and dry climatic conditions.GAMBIT software is used to establish the calculation area of the inlet flow field for spray evaporation cooling and the meshing is carried out.ANSYS FLUENT software with set the energy equation,turbulence model,component transport,DPM,boundary conditions,solution settings and so on,is used to simulate the spray evaporation cooling in the inlet air pipeline,simulating the effects of inlet air temperature,relative humidity and inlet wind speed on the vaporization distance of droplets.The results show that the higher inlet air temperature,the lower relative humidity,the appropriate reduction of inlet air velocity can reduce the distance of droplet vaporization.The designed inlet air pipeline is shorter and the cost is lower.In this paper,the main equipment characteristics of gas-steam combined cycle are analyzed and studied.The main equipments of combined cycle are modeled by the differential evolution method combined with the operating data and design data of gas-steam combined cycle 6F in a certain place,digging out the relationship between the parameters of gas-steam combined cycle,thus obtaining the law of the energy consumption of gas-steam combined cycle changes with the ambient temperature.After installing the spray evaporation cooling device,the energy consumption of the gas-steam combined cycle becomes smaller under the same environmental conditions,and the cost recovery is estimated within 4 years.