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The aim of this paper is to calculate the heat loss and annual energy demand for heating of an administrative building for three variants of thermal-technical design and their evaluation. The heat losses were determined according to the legislation in force and in accordance with the normative requirements. The calculations made can be used in the next phase for the design of the heat source and heating system for heating and for the design of forced ventilation with heat recovery. Based on the optimum choice of technical equipment, it is also possible to evaluate the investment and operating costs for the installation of the different heating and ventilation concepts. Given the current significant increase in energy prices, the present topic is very topical.

The present paper is focused on the mathematical and graphical determination of temperature and thermal parameters depending on the heat dissipation from solidifying steel in the mould, respectively in the primary cooling zone of continuous casting of steel (CCS). The main task of the primary cooling is mainly to remove heat from the solidifying steel, therefore knowledge of the temperature fields in the precast and mould is important. As part of the present research to evaluate the thermal performance of the mould, the heat flux density dependencies q between the steel and the cooling water in the mould were expressed in the primary cooling region. The cooling water parameters and temperature gradients along the height and perimeter of the working surface of a copper mould insert of square cross-section of 150 x 150 mm and 1 m long were used to determine the heat removal rate from the solidifying steel. The temperature and thermal parameters were determined for the solidification and precooling tasks for two grades of steel with carbon contents of 0.18 wt.% and 0.83 wt.%. Casting speeds were chosen to range from 2.1 m•min -1 to 2.7 m•min -1 and casting temperatures from 1500 °C to 1550 °C. The obtained dependencies were used for numerical simulation in the ProCAST environment.

The continuous steel casting process must simultaneously meet the requirements for production performance, quality and safety against breakouts. Knowing the thickness of the solidified shell, particularly at the exit of the mould, is useful for the casting process control and breakout prevention. Shell thickness is difficult to measure during casting; in practice, it is predicted by indirect methods and models. But after undesired rupture of the shell and leakage of the liquid steel, it is possible to measure the shell thickness directly. This article is focused on the problem of the growth and measurement of the solid shell obtained after the breakout of a round block with a diameter of 410 mm. An original methodology was developed in which a surface mesh of points was created from the individual scanned parts of the block using a 3D laser scanner. Research has shown differences of up to 6 mm between the maximum and minimum shell thickness at the mould exit. A regression function of the average shell thickness on time was found. The results of the real shell growth were further used for the verification of the original numerical model of cooling and solidification of the round block.