The Best Settings of Numerical Models of Axial Gas Turbines for Obtaining Reliable Results and Optimization

Abstract

The authors consider the numerical simulation of the turbine workflow using the RANS approach. More than 80 papers published over the past 5 years in the examined field were reviewed. Their analysis did not provide the unified recommendations for the building the numerical models. The selection of model parameters is usually motivated by general considerations of numerical simulation following the method. None of the papers offered the selection of parameters that was correlated with the turbine structure flow. Many specific simulation issues were not covered at all. For the research, more than 1,000 models of full-size axial turbines (including multistage turbines) and their elements were created. They differed in the number, size, parameters of the elements of finite volume meshes, in turbulence models, in the degree of simplification. The results were compared with the experimental data. From the result, the following conclusions were obtained: 1.A method for developing and optimizing the turbine workflow using numerical simulation based on the RANS approach is proposed. The optimal turbine configuration search is carried out using light computational models based on the simplified channel geometry and the finite volume mesh. Their application makes it possible to reliably find the optimal turbine configuration 2.8 times faster. The characteristics of the selected variants are verified by verification models with real geometry of the channels and a minimum error. 2.Recommendations are given on the parameter selection for finite volume meshes and the turbulence models selection for numerical models of the axial turbines workflow designed to perform optimization and verification calculations.