Various cooling systems for advanced gas turbine jets: efficiency study

Abstract

The paper focuses on foreign and Russian aviation bypass turbojets with an afterburner, studies the design of their turbine cooling systems, and introduces the research findings. For computational research and comparative analysis, we used Russian and foreign samples of advanced bypass turbojets with an afterburner with the most optimal technical characteristics, made calculations of the gas-dynamic parameters of their cooling systems in four critical jet operating modes. In this paper, we introduce the results of hydraulic calculations of various schemes for supplying cooling air to the nozzle and working blades of a high-pressure turbine. Relying on the results of the calculation, we comparatively analyzed the foreign and Russian cooling systems design, in terms of power indicators and efficiency of a gas turbine jet. To do this, we used the following parameters: cooling air bleeding value at maximum jet speed and cruising mode, value of cooling air leakage through the axial gaps into the flow path, the change in the cooling air bleeding value as a percentage of the flow rate through the high-pressure compressor when switching from maximum to cruising mode, i.e. adaptability of the cooling system, the temperature of the cooling air at the point of supply to the cooling cavities of the blade of the nozzle apparatus or the working blade.