Development of a multiphysics model to analyze the thermo-mechanical cutting fluid effects in the turning process

• Applicant: Professor Dr.-Ing. Thomas Bergs
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering
• Term: since 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 403801854

The goal of Phase 2 is to transfer the models and insights developed in Phase 1 for orthogonal cutting to the turning process. This aims to achieve a deeper understanding of the thermodynamic effects of coolants and to optimize coolant strategies in terms of nozzle geometry, positioning, and flow guidance efficiently, without requiring extensive empirical investigations. The objective is achieved by extending the numerical process simulation from Phase 1. The scientific challenge lies in the coupled simulation of various 3D models, particularly in the requirements for geometry meshing and model setup. A comprehensive model analysis, including the simplification of turbulence, is conducted to determine optimal model settings for the simulation of high-pressure coolant supply. Another step in the project is the development of a multiscale approach for the turning process based on orthogonal cutting. This approach enables an efficient and user-friendly analysis of the coolant effects on the turning tool. The cutting cross-section is divided into segments and approximated to the chip formation of an orthogonal cut. The effect of the coolant on the turning tool is determined by integrating the segmented cuts. The scientific insights of the project include a deeper understanding of the mechanisms of coolant effects during the turning process. The developed simulation approach enables, for the first time, the analysis of the thermo-mechanical tool load for complex processes considering the coolant. These insights provide a theoretical basis for the design of coolant supply and tool geometry. Additionally, the development of multiscale methods for coolant simulation creates the scientific foundation to extrapolate results from simple orthogonal cuts to complex machining processes. This model simplification could also be applied to other processes like milling in the future. The developed model approach allows predicting the coolant effect on the chip formation process and the transient temperature field in the tool for defined process parameters. This is fundamental for determining the process parameter limits. Furthermore, the approach can simulate the effect of coolant supply parameters on process state variables, enabling targeted adjustments to the coolant strategy without extensive empirical investigations. This reduces tool wear and thermo-mechanical stress on components, lowers development costs, and maximizes process performance.

• DFG Programme: Research Grants