Analysis Of Thermal Radiation Characteristics Of Hot Components In Gas Turbine

Gas turbine plays a vital role in national defense and industrial development, to meet the demand for higher performance, the internal gas temperature becomes higher and higher, which puts a severe test to the security and stability of gas turbine. In such a high temperature environment, radiation heat transfer has become one of the heat sources that can’t be ignored, so it has vital significance to study the distribution of parameters as temperature and radiation heat flux in the radiation field for improving the thermal environment in gas turbine.In this paper, with the model of gas turbine annular combustor and turbine blade, the effects of radiation heat transfer was researched under Fluent and Fortran. The main contents are as follows:1. Radiant heat environmental prediction and analysis in the combustion chamber with film cooling structure: using Fluent, calculation and analysis of the effects by different conditions on the temperature distribution and the spatial distribution of radiation heat flux in the radiation field was done. Conclusions are as follows: when the pressure reduced, the biggest increase in wall temperature was 255 K, the maximum incident radiation heat flux raised 29W/cm2. When GOR increased by 0.01, the maximum temperature increased by 245 K, the maximum incident radiation heat flux raised 135W/cm2; compared with the result without radiation, the wall temperature raised, the maximum rising in the flame tube was 219 K.2. Radiant heat environmental prediction and analysis in the turbine zone: analysis of the results of Fluent and the conclusions are as follows: In general, when the intake pressure decreased, the wall temperature and incident radiation heat flux increased, but in some area the change is more complex. The highest surface temperature of blade and casing were 2048 K and 2008 K, the maximum incident radiation heat flux were 310 W/cm2 and 283W/cm2; when GOR increased 0.01, the highest surface temperature of blade and casing raised 344 K and 364 K, the maximum incident radiation heat flux raised 252 W/cm2 and 236W/cm2; compared with the result without radiation, the wall temperature raised, the maximum rising in turbine area was 174K;3. Research of finite volume method based on K-distribution method of the radiation transfer in combustion chamber and turbine section: considering the spectrum selectivity of non-gray gas and calculation efficiency, the spectral bands were divided into 150-1000cm-1 and 1000-9300cm-1, using K distribution method to calculate the absorption coefficient, and developed the algorithm of heat radiation environment in complex body with unstructured finite volume method. The conclusion are as follows: Compared DO model with FVM model, the results of the two models were different, the maximum difference was 55 W/cm2, but the location and size of the high heat flux and low heat flux was substantially same; In the turbine area, the former is higher than the latter and the fluctuation trend of the two was same as each other.