Comparative strength analysis of two popular options of the radial centrifugal fan impeller design used in horizontal conveyor dryer for fine-grained raw materials is presented. Three types of materials for impeller manufacturing—ASTM A36 steel, Hardox 450 steel and aluminium alloy 6061-T6 are considered. The finite element method (FEM) has been used to investigate stresses and deformations of the impeller within the operational speed range. Analysis shows that the better design is the impeller made of Hardox 450 steel with a central disk. Although the maximum stress is slightly higher in the blades slot for central disk fitting for this design option, it has greatly reduced stresses in contact edges with two other disks (by 22–38%) and blades bending deformation (by 51%). For this design, the maximum operational rotation speed is 1135 min${}^{-1}$ according to the yield strength with a 15% safety factor, while for basic design, it is 1225 min${}^{-1}$. The rational choice of material depends on maximum value of the yield stress to density ratio as well as taking into account the operating conditions and required fan performance. Recommendations for manufacturing the centrifugal fan impeller related to chosen material are given.

The screw feeder design for the pre-compaction of bulk materials to be briquetted in a roll press is considered to increase the overall reliability. The relationship between the parameters of the screw feeder and its technological characteristics is investigated by the example of two fine-grained materials. A new mathematical model and design algorithm have been developed, which takes into account the properties of materials, the roller press parameters, the shape of the briquettes, and their deformation after compaction. The relationship between the pre-compaction pressure and the material stack height at the inlet is determined. The relations between the torque, the screw pitch, and the material stack height above the inlet, as well as the drive power and the screw pitch on productivity, are investigated. In experiments, using the proposed design, the compaction ratio of the peat increases by 22-27%, and hydrolyzed lignin – by 14-17%. The proposed approach allows for preventing drive overloading and ensures the reliable operation of pre-compaction devices for the roller presses.

The idea of this research is to develop a method of airflow velocity measurement in underground mines having a network of long-distance crossing tunnels, where inspections of the ventilation system are required. Currently, this time-consuming procedure is conducted manually, but it has great importance when the mine configuration is subjected to changes. The method is based on the measurements of UAV trajectory deviation when it crosses the lateral air streams while moving along the tunnel. The signals of the gyroscope from the Inertial Measurement Unit (IMU) are used as indicators. The calibration of the proposed method has been conducted in laboratory conditions similar to real conditions. The minimal sensitivity of 0.3 m/s required by regulations is achievable for small drones, and the error is less than 5%. The maximum measured airflow velocity depends on the UAV model and its stabilization system. Recommendations are formulated for method implementation in practice.

The development of efficient parallelization strategies for numerical simulation methods of fluid, gas and plasma mechanics remains one of the key technology challenges in modern scientific computing. The numerical models of gas and plasma dynamics based on the Navier-Stokes and electrodynamics equations require enormous computational efforts. For such cases, the use of parallel and distributed computing proved to be effective. The Grid computing environment could provide virtually unlimited computational resources and data storage, convenient task launch and monitoring tools, graphical user interfaces such as web portals and visualization systems. However, the deployment of traditional CFD solvers in the Grid environment remains very limited because basically it requires the cluster computing architecture. This study explores the applicability of distributed computing and Grid technologies for solving the weak-coupled problems of fluid, gas and plasma mechanics, including techniques of flow separation control like using plasma actuators to influence boundary layer structure. The adaptation techniques for the algorithms of coupled computational fluid dynamics and electrodynamics problems for distributed computations on grid and cloud infrastructure are presented. A parallel solver suitable for the Grid infrastructure has been developed and the test calculations in the distributed computing environment are performed. The simulation results for partially ionized separated flow behind the circular cylinder are analysed. Discussion includes some performance metrics and parallelization effectiveness estimation. The potential of the Grid infrastructure to provide a powerful and flexible computing environment for fast and efficient solution of weak-coupled problems of fluid, gas and plasma mechanics has been shown.

The challenges of improving the quality of the automatic control systems of autonomous vehicles are studied. The methodology of the adaptation of video compression technologies for networks with variable and unstable bandwidth is considered from the perspective of a systematic approach to the development of automatic control systems for self-driving vehicles. A modification of the MJPEG-based video stream compression and transmission algorithm is proposed, that allows transmitting up-to-date data and obtaining images of maximum quality in conditions of non-guaranteed network bandwidth. The performance and reliability of the proposed algorithm have been verified during the field tests.

The work proposes a technology for using a blockchain database to improve the quality of control systems for dynamic objects and technological processes in situations where the stability of communication systems is not ensured or loss of information and control signals is possible. The developed technology (hereinafter referred to as "reverse blockchain technology") involves the calculation of management signals based on a comparison of data from the blockchain database and forecast results obtained at the time of loss of the information signal. The description of the dynamics of the control object is considered in matrix form. Model experiments were carried out to select computational methods for processing signals and forming forecasts for the dynamics of an object. Recommendations are formulated to improve the reliability of control systems in conditions of instability of communication channels.