Tomáš Mauder – PhD thesis on Optimisation of continuous steel slab casting with the use of the temperature field numerical model
The thesis concerns with optimisation of operation of continuous steel slab casting facility. It summarises fundamental analytical and empirical findings about the solidification process, numerical modelling and selected optimisation techniques. It also states the physical conditions and factors influencing the final quality of steel, including their mutual interactions. The solution is based on an original off-line numerical model of the temperature field and its validation against real operation data. The model is extended by an optimisation fuzzy logic based model which is applied to optimisation of the process control. Its versatility is demonstrated by several cases e.g. finding the right casting parameters to produce high quality steel, reaction to emergency situations, finding the optimum relationship between individual casting parameters etc. Within the frame of the optimisation results, the thesis analyse recommended changes to the casting line of a particular continuous casting facility with the aim to reach higher surface temperature of the blank around straightener rolls. The entire concept of the numerical and optimisation model is general to such extent that it is applicable to any slab or billet steel casting.