Modeling and Simulation
| BOOTH 49 In front of E 105 | Computational Photonics Engineering When dealing with laser radiation in the field of material processing, laser measurement applications or in developing laser sources one is always faced with the problem of beam guiding and shaping. For the proper design of optical components and systems the use of numerical tools is most often inevitable. In some cases it is sufficient to treat the laser radiation in the geometrical limit taking laser beams as light rays. But often the coherence and small transverse dimensions of the laser beams make it necessary to consider the wave nature of laser radiation. Basically this means to solve Maxwell equations in some approximate form. The most widely used approximation is the paraxial approximation that leads to the solution of the Fresnel integral or equivalently the SVE-approximation of the Helmholtz equation. For wide angle beam propagation as is for example the case with high NA focusing other numerical methods have to be employed. Contact Person Dr. Rolf Wester Phone +49 241 8906-401 rolf.wester@ilt.fraunhofer.de Fraunhofer Institute for Laser Technology ILT | |
| BOOTH 38 In front of E 100.MB1 | Interactive 3D-Process Simulation for Laser Cutting Laser cutting is an industrially established production technology. Nevertheless there is a great influence of dynamical processes on production quality regarding high cutting speeds assuring efficient facility utilization as well as for low cutting speeds, which are used to cut contures accurately. For finding suitable control directives experimental diagnosis is found to be crucial. Physical modeling is therefore always based on experimental evidence. Quality features such as surface roughness or adherent dross are caused by the dynamics of the process. The various process states and characteristic phenomena (e.g. evaporation, drop formation, gas flow) are visualized in a process simulation and have been experimentally validated. The process simulation reproduces experimental details, observed by the diagnostic system and makes it possible to retrieve possible strategies to avoid defects like adherent dross. Contact Person Dr. Jens Schüttler Phone +49 241 8906-680 jens.schuettler@ilt.fraunhofer.de Fraunhofer Institute for Laser Technology ILT | |
| BOOTH 42 In front of E 100.MB4 | Modeling and Simulation of Laser Keyhole Welding Laser welding is a well established production technology, which in the industrial application is rated by productivity and product quality. Nevertheless there seems to be still a certain potential for a design optimization based on physical modeling and numerical simulation. The extension of suitable process domains by a modified process control is therefore based on a fundamental understanding of the physical processes occurring in laser welding applications. An interactive process simulation for laser welding applications based on an approximative model has been developed, which resolves the form of the welding capillary and gives the dimensions of the weld pool in axial and azimuthal direction. Whereas commercial tools for laser welding model a fictitious heat source according to experimental data like metallographic cross-sections, the process simulation gets the weld pool dimensions from the underlying physical processes like the diffusion of heat and the fresnel absorption on the capillary surface. It has been validated against experimental data. Contact Person Dipl.-Phys. Ulrich Jansen Phone +49 241 8906-680 ulrich.jansen@ilt.fraunhofer.de Fraunhofer Institute for Laser Technology ILT |
