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The mathematical model and numerical simulations of the mechanical phenomena in the gantry crane are presented in this paper. The design of modern mechanical constructions is a complex task that requires use of appropriate tools. Such a modern tool, that gives a broad opportunity to analyze strength parameters of designed structures, is numerical simulation which uses the various numerical methods. Here the problem was solved by the finite element method. The analysis of the stresses and strains of the structure of gantry crane was made using the advanced software with highly efficient possibilities of modeling. Motion of the crane trolley along the beam was also taken into account in the study. The research performed, allows the evaluation of the stress state, pointing out the critical areas and values which are made in order to increase the strength of the structure of the gantry crane. The results of numerical simulation are presented in the form of the fields of Huber-Misses stress for the selected location of the crane trolley. [ABSTRACT FROM AUTHOR]

The work concerns the numerical prediction of deformations in welding of two rectangular profiles using TIG method. Numerical analysis of thermomechanical phenomena are carried out in the Abaqus FEA software using finite element method. Geometry of the joint is numerically recreated on the basis of the real welded joint of rectangular profiles. For this geometry a discretization of the system and numerical simulations of welding deformations are performed. The calculations are performed for the rectangular profiles made of steel X5CrNi18-10. Numerical analysis takes into account thermomechanical properties of welded elements changing with temperature. DFLUX subroutine is used in Abaqus software, allowing the modeling of moveable welding heat source. Mathematical Goldak‘s description of the heat source is assumed to described the distribution of movable heat source power. Results of numerical analysis of the temperature distribution in the welded joint are presented in this study. The estimation of the shape and size of melted zone is performed as well as the prediction of stress state and welding deformations. Numerically predicted deformations are compared with results of the measurement. [ABSTRACT FROM AUTHOR]

Numerical prediction of deformations in laser-welded joints is important at the stage of construction design. The work concerns the modeling and numerical analysis of thermomechanical phenomena occurring in the laser welding process. Three dimensional discrete model of pipe-to-flat fillet weld is created in Abaqus FEA engineering software. Numerical analysis takes into account changing with temperature thermomechanical properties of welded plate made of austenitic steel. Additional numerical subroutine included into the solver takes into account a mathematical model of heat source power distribution. It is assumed that the heat source is moving in the polar system. The positioning of the source relative to the joined edge is taken into account in the analysis. [ABSTRACT FROM AUTHOR]

Numerical analysis of thermal treatment processes is an important issue to be considered by contemporary laboratories dealing with industrial designing in general. Phenomena associated with heat treatment are complex and not yet adequately explained. Improvement in this field of numerical solutions is particularly forced by industry which, striving for deployment of state of the art technologies and reduction of costs, is demanding continuous enhancement of tool thermal treatment. Phase transformations, in particular in cooling processes, involve considerable changes in kinetics that are not always associated with external thermal impact. Analyses of experimental data allowed developing many mathematical models to measure volume fractions of phase transformations in solid state. The Johnson-Mehl Avrami equation and generalised Kolmogorov equation are the two primary models applied in almost all tests evaluating transformation of austenite into ferrite, bainite and martensite. In order to calculate the martensitic phase volume fraction, usually the Koistinen-Marburger equation, or any of its modified formulas, are used. [ABSTRACT FROM AUTHOR]

The laser-arc hybrid welding is widely used in many industries through the combination of advantages found in welding technologies used in this single process. A significant issue is the determination of the influence of heat source power distribution on welding deformations generated at the interface of joined elements and adjacent zones. Numerical estimation of welding deformations is very important and allows for the proper selection of technological parameters as well as the prediction of welded joints quality. This work concerns numerical simulation of thermomechanical phenomena in hybrid welding of sheets made of X5CRNI18-10 steel using laser beam and electric arc heat sources. Three dimensional discrete model is created in Abaqus FEA in order to estimate welding deformations generated by temperature field in the joint. Additional numerical subroutine is created in Abaqus/Standard module in which the distribution of movable hybrid heat source is implemented. The shape and size of the fusion zone is determined on the basis of numerically obtained temperature field as well as welding deformations occurring in hybrid butt-welded joints. [ABSTRACT FROM AUTHOR]

This work concerns mathematical and numerical modelling of temperature field during hybrid welding process using Yb:YAG laser and electric arc in GMAW method. Numerical analysis is performed taking into account the motion of liquid steel in the fusion zone. Yb:YAG laser power distribution is determined on the basis of experimental research made on TruDisk 12002 laser. Geostatistical Kriging method is used in the interpolation of Yb:YAG laser power intensity distribution. Temperature field and melted material velocity field in the fusion zone of hybrid welded sheets made of S355 steel are obtained on the basis of numerical solution of continuum mechanics equations in Chorin's projection method and finite volume method. Experimental research of laser beam profile is performed in order to verify the correctness of developed heat source model. Fusion zone and heat affected zone geometry is predicted on the basis of calculated temperature field in the cross section of hybrid welded joint. [ABSTRACT FROM AUTHOR]