FEDORKO, T. Řešení přenosu tepla tuhnoucí ocelové soustavy se změnou fáze při pohybujících se okrajových podmínkách [online]. Brno: Vysoké učení technické v Brně. Fakulta strojního inženýrství. 2019.

Posudek vedoucího

Štětina, Josef

The aim of this master’s thesis is to implement a numerical model for solution Heat transfer solution of solidifying steel system with phase change with moving edge conditions This theme is used to model the continuous casting of metals. As a test case was chosen the slab casting machine (Vitkovice Steel). The advantage of simplifying the 3D area to a 2D area shift with variable boundary conditions is, in particular, the reduction of computational time. The problem solved is strongly non-linear due to the dependence of the thermophysical properties of steel on the temperature, but especially the latent temperatures associated with the phase change. To solve this problem, the work selected three approaches are compared. The text of the thesis has 65 pages of text and attachments containing scripts in MATLAB. Work includes all required parts. Graphic design meets the technical text. The student used a wide range of resources, including the Internet. The difficulty of programming the whole issue for three different approaches was time-consuming, resulting in a lack of time to test and verify the program code. This has resulted in a lack of time to make a final comparison of methods and results. But work is a good basis for further developing methods based on variable boundary conditions. The student demonstrated the ability to work independently, fulfilled the conditions of the assignment, the thesis contains all the essentials, and therefore I recommend it for the final exam.

Posudek oponenta

Mauder, Tomáš

The master's thesis aim to develop a 2D numerical slice model with moving boundary conditions for continuous casting problem. Different solidification models are tested. Numerical model is created in MATLAB environment. The thesis has eight section including introduction and conclusion. The first parts describe continuous casting process. Section 4 describes mathematical model. Section 5 shows numerical formulation and section 6 implementation. Section 7 discussed the results and section 8 conclude results with future possible extensions. Graphical style is on good level, only some figures should be placed in better quality (see fig. 4, 6, 14 etc.). Text overflow in figure 22 does not look good. The work with literature references is fine. The content of the work fulfils the master's thesis goals. Only the part where the thesis should define moving boundary conditions is missing (section 5.2 is too short with no detail explanation). The results are clear, but from table 3 and table 4 the reader may feel that the finer mesh is more accurate than the finest one in case of Enthalpy method. The thesis is written clearly, graphically on a good level with a minimum of formal mistakes. I recommend the thesis.

eVSKP id 113000