Abstract
<jats:p>The research focuses on the durability of the rotor blades of a marine gas turbine engine. The goal of the research is to determine the maximum equivalent stresses and the durability of the rotor blades of a ship gas turbine engine under the action of the working fluid flow. To achieve the aim of the research, the following research tasks were addressed: developing a high-precision mathematical model for calculating the fatigue strength of marine gas turbine engine rotors, which reliably reflects the actual operating conditions while ensuring the accuracy of the results; determining the influence of the gas flow temperature and pressure on blade durability; and analyzing the influence of blade’s cooling cavity design on the level of maximum equivalent stresses. The methods employed include numerical methods, in particular the finite element method. The following results were obtained: the problem of determining the equivalent dynamic stresses and durability of gas turbine blades was solved in the work. The numerical results were used to determine the operational lifespan of the rotor blades. Equivalent stresses and service life were determined for the most critical frequencies of forced oscillations across all turbine stages, that constitute the rotor. A marine gas turbine engine must be as compact as possible. Thus, its rotor consists of only three stages, which results in considerable vibration and thermal loads on the rotor blades. It was established that the blades of the first stage, which are exposed to the highest thermal and vibration loads, have the lowest durability. The scientific novelty lies in the development of an improved mathematical model for determining the durability of blades of marine and stationary gas turbine engines. Conclusions. The calculation results show that at a surface temperature of approximately 1000 °C, the maximum equivalent stresses are approximately equal to the endurance limit of the blade material. The influence of the geometric parameters of the blade cooling cavity on the value of the maximum equivalent stresses was also investigated. The results obtained can be used for subsequent research related to rotor creep and the initiation of fatigue cracks on the blades surfaces.</jats:p>