математична модель

Passenger transportation by rail is an important component of ensuring cross-border cooperation between our country and neighboring EU countries. Transport transformations are being carried out on both sides of the border, and directives are being developed and implemented to establish uniform rules and standards for the successful operation of transport and passenger movement. At the same time, the organization of traffic is being improved, taking into account the features of the infrastructure, as well as changes in traffic flows, in particular passenger flows at border areas.

Single-phase commutator motors (SPCM) with sequential excitation have a simple design and low cost, and therefore promising for use in the drive of household appliances and electric hand tools. This necessitates the creation of mathematical models of SPCM, which would allow both the development of new and modernization of existing models of such motors. The aim of the article is to create an engineering mathematical model of the magnetic state of SPCM using circular methods.

The results of mathematical modelling of the turbine unit with the K-325-23.5 steam turbine are presented. The mathematical model of the turbine is a system of equations for the components of the heat-balance diagram and the main dependencies of its operating characteristics obtained through the thermal full-scale tests. The developed mathematical model allows adjusting the results of the full-scale tests, creating normative characteristics and conducting research of the intermediate modes of the turbine operation.

The deviation of density and viscosity values of oil mixtures from those calculated according to the additivity rule has been examined. Mathematical models have been developed for determining the properties of mixtures with different compositions taking into account the group composition of the source components. Mixtures containing components with a high content of alkanes and a low content of arenes have been found to be characterized by extreme deviations of density towards the maximum and kinematic viscosity towards the minimum.

Aim. The aim is to construct the mathematical model of the movement of loose material in a vibrating separator. Method. The calculation scheme of the vibration separator with two eccentric vibrators with an independent drive was built. Based on the scheme, it is assumed that the vibration separator performs only vertical oscillations in the plane of rotation of the eccentric vibrators.

Modern high-torque low-speed internal combustion engines (ICEs) generate torsional vibrations close in disturbance frequency to gearboxes natural oscillation frequencies. Effective absorption of such oscillations requires a new torsional vibration damper between the internal combustion engine and gearbox design, which is implemented in the form of a dual-mass flywheel (DMF). One of the main reasons for DMF failure is its spring components destruction.

The dynamics of the adsorption process in the fixed-bed column was experimentally studied on the example of the system natural zeolite - water solution of copper salt with low concentrations, which are characteristic for wastewater treatment processes from toxic contaminants. The initial curves of the adsorption process for the height of the sorbent layer of 5 and 7 cm were constructed. The equilibrium of such processes can be described by Henry's linear equation. The adsorption process in the layer consists of two stages, which are examined in the study.

The extraction of the solid component from the rectilinear capillary has been investigated. The presence of two extraction zones (convective and molecular diffusion) was confirmed. The effect of the system vacuumizing on the extraction rate has been studied. The convection zone during vacuumizing was found to be increased due to the appearance of the vapor phase bubbles. The mass transfer coefficients for the convective zone have been determined.

The article proposes a solution of the forward kinematics problem for a welding manipulator with six degrees of freedom. Solving this problem is the first necessary step in creating a control system for this manipulator. This will make it possible to determine the displacement, accelerations and moments in each of the manipulator parts and will ensure accurate positioning of the welding tool.

The arc overvoltages during the single phase to earth faults in electrical distribution grids of 6-35 kV are the object of the research in this paper. The development of 35 kV distribution electrical grids is accompanied by the construction of new overhead and cable power lines. It causes a change of the capacitive earth fault current in the grids and also affects the multiplicity of overvoltages in electrical distribution grids during the single phase to earth faults.