Determination and Application of Double Ellipsoid Heat Source Model Parameters

In this paper the technique of parameter identification is investigated to reconstruct the 3D transient temperature field for the simulation of laser beam welding. The reconstruction bases on volume heat source models and makes use of experimental data. The parameter identification leads to an inverse heat conduction problem which cannot be solved exactly but in terms of an optimal alignment of the simulation and experimental data. To solve the inverse problem, methods of nonlinear optimization are applied to minimize a problem dependent objective function.In particular the objective function is generated based on the Response Surface Model (RSM) technique. Sampling points on the RSM are determined by means of Finite-Element-Analysis (FEA). The scope of this research paper is the evaluation and comparison of gradient based and stochastic optimization algorithms. The proposed parameter identification makes it possible to determine the heat source model parameters in an automated way. The methodology is applied on welds of dissimilar material joints.

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Heat source model for electron beam welding of nickel-based superalloys

Materials Testing ◽

10.1515/mt-2020-0002 ◽

2021 ◽

Vol 63 (1) ◽

pp. 17-28

Author(s):

Torsten Jokisch ◽

Nikolay Doynov ◽

Ralf Ossenbrink ◽

Vesselin Georgiev Michailov

Keyword(s):

Electron Beam ◽

Heat Source ◽

Electron Beam Welding ◽

Experimental Studies ◽

Theoretical Models ◽

Source Model ◽

Beam Deflection ◽

Prediction Algorithm ◽

Model Parameters ◽

Heat Source Model

Abstract An adapted heat source model is developed for transient thermal numerical analysis of electron beam welded nickel-based alloy with increased susceptibility to hot cracking. The model enables the consideration of heat redistribution due to beam deflection phenomena. The modeling concept is validated by the appropriate theoretical models and in addition, experimental studies especially performed for this purpose. Special attention is given to the calibration of heat source model parameters. The calibration procedure is based on a statistical approach involving a combination of novel analytical solutions and quasi-steady state finite element models. The model parameter field is statistically analyzed, and a prediction algorithm is developed using optimization algorithms from the six sigma theory. The reliability and practicability of the model is demonstrated by validation weldments. The work is dedicated to precisely calculating the temperature field in the high temperature region around the weld pool and thus to provide a more detailed explanation of the formation of hot cracks when welding turbine materials commonly used in industry and aircraft constructions.

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Estimation of heat source model parameters for twin-wire submerged arc welding

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-009-2046-3 ◽

2009 ◽

Vol 45 (11-12) ◽

pp. 1096-1103 ◽

Cited By ~ 28

Author(s):

Abhay Sharma ◽

Ajay Kumar Chaudhary ◽

Navneet Arora ◽

Bhanu K. Mishra

Keyword(s):

Heat Source ◽

Arc Welding ◽

Source Model ◽

Submerged Arc Welding ◽

Model Parameters ◽

Heat Source Model ◽

Submerged Arc

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Numerical Simulation and Experimental Research on Temperature Distribution of Fillet Welds

Materials ◽

10.3390/ma13051222 ◽

2020 ◽

Vol 13 (5) ◽

pp. 1222 ◽

Cited By ~ 1

Author(s):

Shanchao Zuo ◽

Ziran Wang ◽

Decheng Wang ◽

Bing Du ◽

Peng Cheng ◽

...

Keyword(s):

Numerical Simulation ◽

Temperature Distribution ◽

Heat Source ◽

Matrix Equation ◽

Source Model ◽

Fillet Welds ◽

Model Parameters ◽

Heat Source Model ◽

Fillet Weld ◽

The Matrix

In this paper, a matrix equation for the welding heat source model was proposed to calculate the fillet welds temperature distribution based on the penetration depth and molten width. A double ellipsoid heat source model of fillet weld was established firstly by physical experiment and simulation calculation, and then the orthogonal experiment was constructed based on the previous calculation methods and experimentally measured data. Finally, the matrix equation of the heat source model parameters was obtained by regression analysis based on the joint penetration and width. The experimental and numerical simulation of the temperature distribution had been performed for the fillet weld and the results show that (1) the heat flux increases in one direction, while, oppositely, it decreased in another direction; (2) simulation results were highly in accordance with experiments results. The results indicated that the double ellipsoidal heat source model calculated by the matrix equation is quite appropriate for predicting the transient temperature distribution on the fillet welds for the gas metal arc welding process.

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