## 5 Conclusions  
By appropriately selecting numerical simulation settings, it is possible to achieve a relatively good match between the measured and numerically calculated values of the areal density of the oil film deposited on the inner surface of the pipe. The basic problem of using numerical solutions is the considerable dependence of oil deposition over the length of the pipe from a large number of selected parameters. It is essential to correctly select the input speed, the roughness of the pipe and the resistance coefficients. Due to the fact that numerical calculation dealt with the flow of viscous fluid with oil particles, simultaneously taking into account turbulent flow, the pipe resistance is also accounted for in the calculation. However, the paper did not deal with pressure drops due to their irrelevance with respect to the resulting oil fraction layer on the pipe's surface. There is substantial adherence to the speed at the entrance into the pipe and the oil volume fraction (compliance with the margin conditions). The pipe's resistance to the flow of the fluid was causing a pressure drop ranging between 75 and 138 Pa subject to the pipe's diameter (at 5 m\(\cdot\)s\({}^{-1}\)). The deviation of the angle between the pipe axis and the speed at the inlet to the pipe during oil mist injection does not have a significant effect on the distribution of the areal density of the oil film due to the rapid stabilization of the current. As can be seen from Figures 2, 5 and 8, simulation and experimental measurement results are not always accurate. It is due to the imperfection of measurement and simulation. Despite the fact that a strong emphasis was placed on the best possible simulation, as can be seen in Figure 1, as the cross-linking of the elements with respect to the most serious object where the trapped oil micro particles are made, there is still a large amount of input variables into the simulation software. The simulations themselves were performed on a high-performance computer with 36 processor cores, one simulation lasting over 24 h. However, it can be said that the results of simulation, despite its imperfection, can be considered to be the same as experimental measurements, which we consider to be the starting point for further reflections on the investigated issue. Experimental measurement also involved a number of influential factors that had to be unified within the individual metering occurrences and eliminated as much as possible. The resulting graphs of the dispersion oil fraction plot for the different pipe diameters can be taken as the primary information for possible real use in practice. In general, it can be said a few important findings have been made and recommendations should be respected:  
* The pipes during the application of the dispersion oil fraction should be rotated to achieve a uniform distribution of the oil layer along their inner surface. * The entry of the dispersion oil fraction through the nozzle must be as accurate as possible, aligned with the pipe axis, and the angle between the axis of the pipe and the nozzle axis should be the same. * Ensure the texture of the dispersed oil fraction without dirt and air bubbles is consistent. * Ensure the ambient parameters, such as: temperature, flow rate of the dispersion oil fraction, air pressure in the compressor reservoir are stable, ensure that the opening for the dispersed oil fraction to escape the treated pipe is open. After observing the above parameters, the method can be used to coat steel (or other materials) pipes and thereby obtain the desired anticorrosive protection of the inner surface of slim pipes. [PERSON] suggested the concept of coating the inner surface of slim tubes with of a dispersed oil fraction; [PERSON]. ([PERSON]) and [PERSON] designed and performed experimental measurements in the laboratory; [PERSON] analyzed the data and suggested a calculation model for estimating the thickness of the oil layer; [PERSON] performed a numerical coating simulation; [PERSON].