MODELING THE OPTIMUM HEAT REMOVAL IN THE SYSTEM OF COOLING OF SHELL BLADES OF A GAS-TURBINE ENGINE ON THE BASIS OF A DURABILITY CRITERION

The focus of the study is raising the efficiency of heat removal in shell blades of a gas-turbine engine with the internal cooling system. A mathematical heat-removal model has been proposed that allows minimizing the mass flow rate of a cooling liquid due to the implementation of a thermally stressed state in the body of a turbine blade, which satisfies the durability criterion. The model makes it possible to reduce the nonuniformity of distribution of the durability life in the turbine-blade′s body, which results from the nonuniform stressed state and the nonuniform heating on the heat-supply surface of the blade. A mathematical formulation of the problem of the study was based on the equations of heat transfer under the conditions of steady-state heat transfer. A numerical model of calcu- lation of the pattern of coolant velocities and variable width of heat-removal channels was constructed with the finite-difference method. From the results of the study, the authors have analyzed the influence of the turbine-blade speed on the change in the geometry of heat-removal channels, at which a uniform thermally stressed state of the blade is ensured according to the durability criterion. The approach considered in the study may be used in cooling deflector-type blades of a gas-turbine engine. The proposed mathematical model will allow reducing the irrational mass flow rate of the coolant in less heat-loaded portions of the blade, and also raising the intensity of heat removal in more heat-loaded regions

Author:  I. K. Andrianov and E. K. Chepurnova
Keywords:  heat removal, turbine blade, durability, thermally stressed state
Page:  816