Numerical Simulation Of Conjugate Heat Transfer In A Turbine With Newly Designed Cooling Structure Of Second Stage Blade

Gas turbine is widely used in the fields of aviation gas turbine propulsion, power generation and shipping and so on, playing a very important role in the national economy, and it has become an very important indicator of national science and technology level, military and comprehensive national strength. Along with the development of the aerospace industry, people demand higher performance of the turbine and to improve the turbine inlet gas temperature appears to be the most effective way of meeting this requirement. However, the demanding temperature has greatly exceeded the capacity of blade material, so to design an effective cooling structure to improve cooling efficiency have become a common topic of designers. This article focus on designing blade cooling structure of this stage blades against heat load character of the second stage of a gas turbine blade and analysing the heat transfer and flow field of the cooling blade structure according to the aero-thermal conjugating numerical simulation.The structure that is used in the calculation consist of the vane and the rotor blade. In the second stage vane,impingement cooling is used in the leading-edge and mid-chord region of the second stage vane and the comparison studies of slot and needle hole is conducted for a large heat load on the trailing edge and the high local temperature. In the rotor blade,enhancement of heat transfer cooling method is adopted by designing channel expanding suddenly and shrink suddenly and smooth channel. The article deals with the account result of the projects , and it carries out the particular description and analysis of the temperature field ,flow field ,pressure and heat transfer coefficient. The results show that the cooling structure of impingement cooling adding needle hole can satisfy the cooling requirement of vane, and cooling efficiency of using needle hole is better than slot in the trailing edge; using expand suddenly and shrink suddenly hole on the rotor blade can satisfy the cooling requirement and the cooling efficiency of using expand suddenly and shrink suddenly hole is better than smooth channel because of the local turbulent flow effect.In addition, in order to take account of cooling efficiency and reduce the losses which is caused by coolant-air injection, this paper progresses numerical simulation to the cooling structure of vane and rotor blade with different cooling structures and get the characteristic of temperature field ,flow field ,and discuss the influence on flow field structure and blade cooling efficiency with different cooling flow rate.