Numerical Research Of MW Class Gas Turbine High Pressure Stage Of Static Blades With Fluid Flow,heattransferandstress Analysis Coupling Methods

With the rapid development of modern aviation industry,we put forward higherrequirements on aircraft engine.Among them, the turbine has an important role in theengine.Britain and Germany has invented the gas turbine engine in the early40’ssuccessively, ever since that, the aviation industry develops rapidly, and the gas turbineengine technology has become a national comprehensive strength. The progress of thegas turbine engine is not only relation with economic development, but also the urgentdemand of the defense industry.To improve gas turbine efficiency, improving the turbine inlet gas temperature is adirect and effective means. At present, the temperature is much higher than bladematerial can withstand high temperatures, so the scientific workers need optimize theimproved cooling system to reduce the negative influence of high temperature of maingas turbine.In this paper,numerical research of MW class gas turbine high pressure stage ofstatic blades with fluid flow,heat transferand stress analysis coupling methods is studied.First,through flow thermal coupling simulation, we get the numerical results of originalcooling design of static vane.On the basis of original cooling result, structureoptimization design scheme was proposed, and the cooling effect of before and afteroptimization has carried on the detailed analysis, the effectiveness of the optimizationscheme is verifiedpreliminary in this paper. For further analysis of how much thechanging structure of the cooling impact on the mechanical behavior of vanes,andultimately providing a basis for blade life assessment, based on the structureoptimization, simulate the aerodynamic stress and the thermal stress, and analyses thecooling structure’s impact on the distribution of internal stress condition.Results show that the local high temperatureappearsin the vane leading edge nearthe blade tip, and the reason is the relatively low pressure caused by the trailing edgecutback making the cooling gas skewing and the cooling gas flow mass in leading edgenear the blade tip decreases, so the cooling in leading edge of vane is notenough.Calculating with the original cooling structure,5.5%cooling flow rate of themain gas is needed to make vane’s surface temperature meet the temperature requirements.According to the results of the analysis, we make the hole at the bottom ofthe cooling chamber near the leading edge to optimize, by diameter of0.4mm and0.6mm respectively.The CFD calculations show that,after the optimization of structure,the cooling gas flow rate of the main gas needed drops to5%and4.44%respectively.Under the condition of the flow field and temperature field,the stress simulationresults show that, the impact of pressure to vane’s deformation and equivalent stress isless than temperature.Joining optimize hole can improve the cooling of the bladeleading edge, but in the optimization of hole in local higher equivalent stress. Joiningoptimize hole can improve the cooling of the vane’s leading edge, does a little effects onvane total equivalent stress，but in the optimizing hole there is the local higherequivalent stress, which is under materialstressallowable values.