Now showing 1 - 4 of 4
  • Publication
    Cooling Capacity of Oil-in-Water Emulsion under wet Machining Conditions
    ( 2023)
    Nabbout, Kaissar
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    Sommerfeld, Martin
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    Barth, Enrico
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    Bock-Marbach, Benjamin
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    Many industrial machining operations are carried out under wet machining conditions. Modelling and simulating fluid-structure-interactions and conjugate heat transfer are still a challenge nowadays. In this paper, temperature dependent heat transfer coefficients (HTC) h(T) are experimentally estimated for wet machining-like conditions in a jet cooling experiment. The transient temperature is thereby used to solve an Inverse Heat Transfer Problem for HTC function estimation. Determined HTC are applied as input in related jet cooling simulation using the Finite-Pointset-Method (FPM) to validate the modeling approach. Additionally, wet cutting simulations numerically highlight the influence of determined HTC h(T) on turning.
  • Publication
    The Influence of Electrode Indentation Rate on LME Formation during RSW
    ( 2022)
    Böhne, Christoph
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    Meschut, Gerson
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    During resistance spot welding of zinc-coated advanced high-strength steels (AHSSs) for automotive production, liquid metal embrittlement (LME) cracking may occur in the event of a combination of various unfavorable influences. In this study, the interactions of different welding current levels and weld times on the tendency for LME cracking in third-generation AHSSs were investigated. LME manifested itself as highpenetration cracks around the circumference of the spot welds for welding currents closely below the expulsion limit. At the same time, the observed tendency for LME cracking showed no direct correlation with the overall heat input of the investigated welding processes. To identify a reliable indicator of the tendency for LME cracking, the local strain rate at the origin of the observed cracks was analyzed over the course of the welding process via finite element simulation. While the local strain rate showed a good correlation with the process-specific LME cracking tendency, it was difficult to interpret due to its discontinuous course. Therefore, based on the experimental measurement of electrode displacement during welding, electrode indentation velocity was proposed as a descriptive indicator for quantifying cracking tendency.
  • Publication
    Fully coupled wet cylindrical turning simulation using the Finite-Pointset-Method
    ( 2021) ;
    Barth, Enrico
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    Quellhorst, Alexander
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    Seifarth, Tobias
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    Nabbout, Kaissar
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    Sommerfeld, Martin
    In industrial machining operations, many turning processes are carried out under wet conditions. In contrast, most simulation tools are only suitable for dry cutting processes due to challenges of modeling fluid-structure-interactions (FSI). In this paper, a wet, fully coupled cutting simulation using the Finite-Pointset-Method (FPM) is presented and validated for industrially relevant cylindrical turning. To facilitate the required reduction of the calculation effort, different routines like adaptive numerical discretization are applied. The results indicate different cutting fluid effects like evaporation areas around the chip.
  • Publication
    Data for a simulation of metal cutting with cutting fluid using the Finite-Pointset-Method
    ( 2021) ;
    Barth, Enrico
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    Seifarth, Tobias
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    Höchel, Maximilian
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    Eisenträger, Almut
    The measurement and simulation data, their preparation and the simulation setup published in this co-submission are related to the article ""Simulation of metal cutting with cutting fluid using the Finite-Pointset-Method"". Wet and dry turning experiments were conducted at the Institute for Machine Tools and Factory Management(IWF), Berlin, Germany. Required adaptions of the used software MESHFREE were performed at Fraunhofer ITWM, Kaiserslautern, Germany. Both institutes collaboratively developed and validated the orthogonal cutting simulation model using the Finite-Pointset-Method (FPM). In this paper all measurement and simulation data and their preparation methods are presented in detail. This includes the preparation methods of process forces, analysis of chip morphology images as well as measured contact lengths on tool rake faces. Moreover, the experimental and simulation data are provided at the Mendeley Data repository. Hence the reader can use the data for own validations and analysis. Furthermore, the used simulation model files are completely published at the Mendeley Data repository. It allows the reader to retrace all settings. In addition, this enables to repeat the simulations and to simulate other process parameter combinations according to own interests.