Analysis of the deep rolling process on turbine blades using the FEM/BEM-coupling

• Published in: IOP conference series. Materials Science and Engineering Vol. 10; no. 1; p. 012134
• Main Authors: Bäcker, V, Klocke, F, Wegner, H, Timmer, A, Grzhibovskis, R, Rjasanow, S
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.06.2010
• Subjects: Accuracy; Aircraft engines; Boundary element method; Compressive properties; Computational efficiency; Computer simulation; Computing costs; Computing time; Coupling; Fatigue strength; Finite element method; Mathematical analysis; Mathematical models; Process parameters; Scale models; Strain hardening; Surface layer; Surface layers; Turbine blades
• ISSN: 1757-899X; 1757-8981; 1757-899X
• DOI: 10.1088/1757-899X/10/1/012134

Highly stressed components of aircraft engines, like turbine blades, have to satisfy stringent requirements regarding durability and reliability. The induction of compressive stresses and strain hardening in their surface layer has proven as a promising method to significantly increase their fatigue resistance. The required surface layer properties can be achieved by deep rolling. The determination of optimal process parameters still requires elaborate experimental set-up and subsequent time- and cost-extensive measurements. In previous works the application of the Finite Element Method (FEM) was proposed as an effective and cost reducing alternative to predict the surface layer state for given process parameters. However, FEM requires very fine mesh in the surface layer to resolve the high stress gradients with sufficient accuracy. The hereby caused high time and memory requirements render an efficient simulation of complete turbine components as impossible. In this article a solution is offered by coupling the FEM with the Boundary Elements Method (BEM). It enables the computing of large scale models at low computational cost and high result accuracy. Different approaches of the FEM/BEM-coupling for the simulation of deep rolling are examined with regard to their stability and required computing time.