TY - JOUR
T1 - A heat-transfer and fluid-flow-based model to obtain a specific weld geometry using various combinations of welding variables
AU - Mishra, S.
AU - Debroy, T.
N1 - Funding Information:
This research was supported by a grant from the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences, under Grant No. DE-FGO2-01ER45900. The authors thank Dr. Todd A. Palmer and Dr. John W. Elmer of LLNL for providing welded samples. The authors thank Mr. Amit Kumar for his comments during the preparation of this manuscript.
PY - 2005/8/15
Y1 - 2005/8/15
N2 - Numerical heat transfer and fluid flow models have provided significant insight into welding processes and welded materials that could not have been achieved otherwise. However, the use of these models has been limited by two major problems. First, the model predictions do not always agree with the experimental results because some input parameters such as the arc efficiency cannot be accurately prescribed. Second, and more important, these models cannot determine multiple pathways or sets of welding variables that can lead to a particular weld attribute such as the weld pool geometry, which is defined by an equilibrium temperature surface. Here we show that the computational heat transfer and fluid flow models of fusion welding can overcome the aforementioned difficulties by combining with a genetic algorithm. The reliability of the convective heat transfer model can be significantly improved by optimizing the values of the uncertain input parameters from a limited volume of the experimental data. Furthermore, the procedure can calculate multiple sets of welding variables, each leading to the same weld geometry. These multiple paths were obtained via a global search using a genetic algorithm within the phenomenological framework of the equations of conservation of mass, momentum, and energy. This computational procedure was applied to the gas tungsten arc welding of Ti-6Al-4V alloy to calculate various sets of welding variables to achieve a specified weld geometry. The calculated sets of welding parameters showed wide variations of values. However, each set of welding parameters resulted in a specified geometry showing the effectiveness of the computational procedure.
AB - Numerical heat transfer and fluid flow models have provided significant insight into welding processes and welded materials that could not have been achieved otherwise. However, the use of these models has been limited by two major problems. First, the model predictions do not always agree with the experimental results because some input parameters such as the arc efficiency cannot be accurately prescribed. Second, and more important, these models cannot determine multiple pathways or sets of welding variables that can lead to a particular weld attribute such as the weld pool geometry, which is defined by an equilibrium temperature surface. Here we show that the computational heat transfer and fluid flow models of fusion welding can overcome the aforementioned difficulties by combining with a genetic algorithm. The reliability of the convective heat transfer model can be significantly improved by optimizing the values of the uncertain input parameters from a limited volume of the experimental data. Furthermore, the procedure can calculate multiple sets of welding variables, each leading to the same weld geometry. These multiple paths were obtained via a global search using a genetic algorithm within the phenomenological framework of the equations of conservation of mass, momentum, and energy. This computational procedure was applied to the gas tungsten arc welding of Ti-6Al-4V alloy to calculate various sets of welding variables to achieve a specified weld geometry. The calculated sets of welding parameters showed wide variations of values. However, each set of welding parameters resulted in a specified geometry showing the effectiveness of the computational procedure.
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U2 - 10.1063/1.2001153
DO - 10.1063/1.2001153
M3 - Article
AN - SCOPUS:25144488096
SN - 0021-8979
VL - 98
JO - Journal of Applied Physics
JF - Journal of Applied Physics
IS - 4
M1 - 044902
ER -