SIMULATIONS-OVERVIEW OF HYBRID SIMULATION MODELS
MSc Bojan Jovanovski * Ss. Cyril and Methodi University, Faculty of Mecahical Engineering, Skopje, Macedonia Dr Robert Minovski Ss. Cyril and Methodi University, Faculty of Mecahical Engineering, Skopje, Macedonia Dr Siegfried Voessner Institute of Engineering and Business Informatics, TU Graz, Austria Dr Gerald Lichtenegger Institute of Engineering and Business Informatics, TU Graz, Austria doi:10.5937/jaes10-2512
A comparison of system dynamics and discrete event simulation
Two popular simulation techniques are system dynamics and discrete-event simulation. However although widely used there is little guidance in the literature on which technique is appropriate to address a particular problem. This paper contains a review of the characteristics of these two techniques in order to provide guidance on their use. In many circumstances it may be that either technique is appropriate and the decision on which technique to use will be determined by the experience and preferences of the modeller for one or other approach. However there is a particular distinction in the techniques in terms of their approach to modelling. The system dynamics method maps a problem onto a generic structure that can help understanding of the underlying causes behind the behaviour of the system. The discrete-event simulation technique attempts to replicate the structure of the system and then allows performance to be measured under a number of scenarios. These approaches have thus different outcomes in that system dynamics can be used to learn the causes of problems and not just treat the symptoms. On the other hand discrete-event simulation is able to track individual resources through the system, show queuing behaviour and generate metrics of process performance.
Numerical Simulation of Induction Heating Process of Continuous Casting Slab
Compared with traditional blazing furnace, the Continuous Casting-Direct Rolling is an advanced manufacturing steel technology, which can reduce energy waste, decrease pollution and enhance efficiency. The characteristics of steels during induction heating are complex, the change of material properties with temperature makes exact analysis methods very difficult to implement. Therefore, a powerful computer aided numerical tool (i.e., finite difference analysis) is selected to numerically model the induction heating process in this paper. The mathematic model coupling with electromagnetic field and thermal field was established, and it was solved by finite difference method (FDM), thus the slab temperature distribution and its variation with time were obtained, and the characteristics in whole induction heating process were studied. To validate the program feasible, the results were evaluated and compared with experiment results, which showed that the simulation results are reliable and effective. The skin effect in heating process from the two results was studied and demonstrated, the temperature change caused by different parameters such as the induced power intensity and the corner radian were also presented, which indicate that the slab temperature can be heated uniformly through adjusting these parameters, thus the continuous casting slab can meet the rolling requirement.