Numerical Simulation And Newly Designed Cooling Structure Of Gas Turbine Blade

Heavy duty gas turbine marks a country’s comprehensive national strength and the level of development of key technology, performance requirement is high and working condition is harsh. The thermal efficiency of gas turbine increases with the increase of inlet temperature of turbine rotor, operating temperature is much higher than the allowable temperature of the blade, the temperature level and temperature change of the blade material must be limited to ensure a reasonable service life. The effective cooling method can not only improve the gas initial temperature,prolong the life of the turbine blade, but it has important significance to improve the efficiency of gas turbine,ensure the safe and stable operation of the unit, reduce pollutant discharge, protect the environment.Compared to air cooling, the advantages of steam cooling are:Steam heat transfer performance is better than air, so the cooling efficiency is higher; Do not need to draw air from the compressor,greatly improve the efficiency of the compressor and the gas turbine. So in this paper moving blades adopt closed steam cooling blade, by numerical simulation of fluid solid coupling calculation,study on the cooling characteristics of the first stage turbine moving blades of gas turbine.Firstly, according to characteristics of different cooling technologies, and different part shape and heating condition of turbine blade,four gas turbine blade cooling structures of gas turbine are designed,they are:(a) Sequence disturbing flow column cooling structure in blade trailing edge; (b) Staggered disturbing flow column cooling structure in blade trailing edge; (c) Inhomogeneous column disturbing flow column cooling structure in blade trailing edge; (d) Inhomogeneous inclined column disturbing flow column cooling structure in blade trailing edge; Solidworks software is used to build four kinds of calculation models of the cooling structure blades.Secondly, FLUENT software is used to simulate blade flow and temperature fields of four different disturbing flow column cooling structures with the same heat load and boundary conditions,compare pressure and velocity distribution of the channel in the leaves, the temperature distribution of blade wall, relative cooling effect, maximum temperature, average temperature and average relative cooling effect of four different cooling structure blades, the results show that inhomogeneous inclined column disturbing flow column cooling structure in blade trailing edge is the best.Finally, fluid solid coupling simulation of temperature, pressure,flow and so on for the best cooling effect model, their heat transfer and flow characteristics are analyzed, discussing the change rules of pressure and velocity distribution of the channel in the leaves, temperature distribution of blade wall,relative cooling effect,maximum temperature, average temperature and average relative cooling effect of the blade under different working conditions. Provide reference for the research of turbine moving blade cooling technology of gas turbine.