Analysing temperature distributions in turbine first-stage rotor blades of a helicopter turboshaft engine

Abstract

In helicopter turboshaft engines, turbine blades operate under extreme conditions. With increasing engine power, the gas temperature following the combustion chamber can reach approximately 1300 K. The turbine rotors endure significant centrifugal forces due to their high rotational speeds. Additionally, they experience thermal and aerodynamic loads from the flow of combustible gases, which non-uniformly impact the turbine blades at high temperatures. Furthermore, the mechanical properties of turbine blade materials are limited and strongly influenced by operating temperatures. This article presents a numerical investigation focusing on the temperature distribution of first-stage turbine rotor blades that do not feature internal cooling channels. The results indicate the regions of peak temperatures and evaluate rotor blade strength. Comparative analysis between theoretical and numerical calculations of blade temperature distribution reveals minor disparities:  approximately 30 degrees at the blade shroud, 8 degrees at the mid-span section, and 15 degrees at the hub. These variations amount to less than 3% at the shroud, 1% at the mid-span section, and 1.5% at the hub.