Investigation of a Temperature Field of the Steel Billet 150x150 mm Continuously Cast

The solidification and cooling of a continuously cast billet and the simultaneous heating of the mold is a very complicated problem of three-dimensional (3D) transient heat and mass transfer. The solving ofuch a problem is impossible without numerical models of the temperature field of the concasting itself which it is being processed through the concasting machine (caster). The application of the numerical model requires systematic experimentation and measurement of operational parameters on a real caster as well as in the laboratory. The measurement results, especially temperatures, serve not only for the verification of the exactness of the model, but mainly for optimization of the process procedure. The most important part of the investigation is the measurement of the temperatures in the walls of the mold and the surface of the slab in the zones of secondary and tertiary cooling

Importance of the experimental investigation of a concasting technology

The solidification and cooling of a continuously cast billet, slab cylinder, generally of a concasting and the simultaneous heating of the mold is a very complicated problem of three-dimensional (3D) transient heat and mass transfer. The solving of such a problem is impossible without numerical models of the temperature field of the concasting itself hich it is being processed through the concasting machine (caster). The application of the numerical model requires systematic experimentation and measurement of operational parameters on a real caster as well as in the laboratory. The measurement results, especially temperatures, serve not only for the verification of the exactness of the model, but mainly for optímization of the process procedure: real process input data numerical analyses optimization correction of real process. The most important part of the investigation is the measurement of the temperatures in the walls of the mold and the surface of the slab in the zones of secondary and tertiary cooling

Analýza možností zavedení standardu blended learning v akreditovaných bakalářských a navazujících magisterských studijních programech FSI

Popis konceptu blended learningu, popis současného vzdělávacího modelu na FSI VUT v Brně, popis možností implementace blended learningu do výuky vybraných předmět

Aerosol deposition in human airways during breathing cycle

A numerical model of the aerosol transport and deposition in human airways is presented. The model was acquired from a CT scan a living person and consist of 6-9 bifurcations giving around 100 terminations of the tree. The oral/nasal cavity was not modelled in the presented work. The deposition of the particles is given for two breathing regimes, the resting conditions with a tidal volume of 0.5 liter and 15l/min ventilation with period of 4sec/cycle and full exercise conditions with 3.33 liter tidal volume and 120l/min minute ventilation with cycle period of 1.25sec/cycle. The aerosol concentration was assumed 50μg/m3 distributed in the three size classes PM10, PM 5 and PM 1. The results shows deposition in different segments of the tracheo-bronchial tree as well as velocity profiles at different time steps of the breathing cycle

CFD analysis of coolant flow in the nuclear reactor VVER440

The paper introduces results of computational fluid dynamics (CFD) simulations of water flow at the reactor pressure vessel (RPV) outlet and under the RPV head. Several CFD calculations of the steady-state and dynamic processes involving forced and natural circulation of coolant are presented in the paper. In the steady-state regime, several calculations were performed for various number of the reactor coolant system (RCS) loops connected to the reactor and the results have been used to analyse the effect of the RCS configuration to the coolant flow at the reactor outlet and under the reactor vessel head. General flow patterns are described in the outlet part of the reactor and under the reactor vessel head and, also, the influence of a lower flow rate through the reactor on thermal homogeneity of coolant under the vessel head. Simultaneously, we discuss the influence of the coolant flow rate at the core outlet on the heat transfer from the under-head space. Unsteady calculation was also done for a reactor cool-down in the regime of natural circulation. The calculation conditions correspond with the data obtained from the experiments led in the frame of the cool-down process of VVER440 reactor at Mochovce nuclear power plant in 2003. In the calculations, the main attention was applied to establishing the basic trends in the cool-down of water content at the outlet part of the reactor and under the head of the reactor vessel

Analysis of the Influence of Boundary Condition on Simulation Accuracy of Solidification Thermokinetics Model

For a sample steel casting of a cylindrical shape that was cast in a metallic cylindrical mould, the analysis of influence and importance of the main boundary condition on the simulation accuracy of the temperature field in the system of casting-mould-environment was performed. For this system, the influence of the boundary condition on the frame of the mould, on the bottom of the mould, on the top of the casting, and on the casting-mould interface was analysed. As a comparing quantity for accuracy, the time-dependent temperature field (by means of isotherms) of the casting and of the mould and the total solidification time were selected. When the simulation considers the boundary conditions of one of these boundaries of the system, the heat transfer coefficient on the remaining three boundaries of the system is equal zero. The resultant heat flow along the axis is zero always. The conclusions can be used for fine-tuning of solidification models as well as for other applications; e.g. analysis and solution of inverse heat transfer problems