Computer simulation of drop impingement erosion of wet-steam turbine blades to identify the efficiency of active erosion preventive measures

The article considers the problem of identifying the efficiency of active erosion preventive measures for wet-steam turbine blades. The erosion prediction technique and software packages based on this technique are also studied. The conclusion is made about the necessity to simulate drop impingement erosion as a process caused by a high-cycle material fatigue as a result of numerous drop impacts on the surface of wet-steam turbine blades. There are described features and adequacy of the software package “Erosion” which simulates the turbine operation and blade erosion. The article provides the results of the computational experiments to identify the dependencies of the erosion rate of turbine blades K-300-240 of the Leningradskiy Metal Plant and the main turbine set of the atomic ice-breaker “Lenin” on the penultimate turbine stage separation coefficient value, backpressure and steam consumption through the turbine stage. According to the computational experiment results and by means of approximation, we received analytical dependencies of the erosion area, lost material weight on various gas-dynamic turbine properties and offered the measures to reduce erosion. These dependencies show the ambiguity of the erosion preventive parameter influence on the erosion of various turbine dimension types which requires computer simulation of erosion for each steam turbine dimension type.