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.

This article presents a description of a novel method for the identification of a decrease in the temperature of a liquid medium transported by railroad tank cars. No exact analytical solution exists for this phenomenon; therefore, the authors of this article have prepared a mathematical expression for the cooling process of the transported fluid by applying a dimensional analysis, which facilitated the identification of the dimensionless criteria using the relevant dimensional parameters. A functional dependence between the criteria can be identified through a physical or numerical experiment. In this case, a database of the results from a detailed numerical model was used; however, its disadvantage is that the calculation takes much longer than in a simpler similarity model. The output of the similarity model was a function of the average temperature of the fluid at a time applicable to various alternatives in the geometrical, physical, and boundary conditions. The standard deviation of the difference between the temperatures predicted by the similarity model and those calculated by the numerical simulation T_mod − T_sim represented 4.8% relative to the simulated fluid temperature.

The paper describes the methodology for determination of the heat exchanger output for mobile container device designed to supply stationary stations with natural gas. Expansion of the gas in the device is considered in two stages. In the first stage from over-pressure of 22 MPa down to over-pressure of 0.4 MPa and then in the second stage to over-pressure of 2.2 kPa or 170 kPa. The overall temperature drop during gas throttling, which depends not only on the initial and final pressure but also on the temperature, was calculated by numerical integration of the Joule-Thomson differential coefficient. For the throttling temperature between 0 and 55 °C, the total temperature drop in the first stage varies between 53.8 and 67.4 K, and in the second stage then up to 2 K. The heat exchanger output was determined by an iterative process. Smooth supply of 600 m3 of natural gas per hour requires a heat exchanger with an output of approx. 26 kW. Gas combustion micro-turbine consumption is of the order of m3 of natural gas per hour.