Inversing Parameter Values Of Double Ellipsoid Source Model During Multiple Wires Submerged Arc Welding By Using Pattern Search Method

During the simulation of multiple wires submerged arc welding, it is very important to define parameters of double ellipsoid source model, and these parameters can make a direct effect on the weld shape, however,it is very hard to get them through practical experiments.The paper mainly discusses the whole process of inversing parameter values of double ellipsoid source model, and makes some conclusions below:1,Carry out butt welding of X70 steel by single wire submerged arc welding, and compared temperature field,weld width and weld depth acquired from experiment to those data acquired from simulation,finally parameter values of double ellipsoid source model are predicted by using Pattern Search Method,namely,C_f1=12mm, C_r1=25mm, Cd1=13mm, Ch1=13mm,and the whole error E=1.7893.2,during the double wires submerge welding, set conclusion 1 as the first double ellipsoid source parameter values, and use the same method to predict the second double ellipsoid source parameter values, namely, Cf2=8mm, Cr2=15mm, Cd2=10mm, Ch2=9mm,and the whole error E=0.9295.3,during the triple wires submerge welding, set conclusion 2 as the first and second double ellipsoid source parameter values, and use the same method to predict the third double ellipsoid source parameter values, namely, Cf3=6mm, Cr3=8mm, Cd3=6mm, Ch3 =10 mm,and the whole error E=1.3539.4,From experiments,simulation and discussion above,demonstrate the rationality and accuracy of inversing the parameter values of double ellipsoid source model in the multiple wires submerged arc welding by using Pattern Search Method.5,Carry out experiment of inversing source parameter values by using one double ellipsoid source model to replace two double ellipsoid source models in the double wires submerged arc welding. From the result we find the simplification of source model is not as well as the original one, because it leads to much more error than original one does.6,Carry out experiments of inversing source parameter values by using one or two double ellipsoid source models to replace three double ellipsoid source models in the triple wires submerged arc welding. From the result we find the simplification of source model is not as well as the original one, because it leads to much more error than original one does. Meanwhile, single source model makes the maximal error, and triple source model leads to minimal error.7,Conclusion 5 and 6 illustrate that less source models replace multiple source models will result in bigger error though it can simplify source model and reduce time consumption of simulation in the multiple wires submerged arc welding. If error is tolerant, the model simplification can be applicable.