On a two-speed mathematical model of two-fluid medium with one pressure

An overdetermined stationary system of second-order differential equations is obtained. For the two-dimensional system, a variational statement of the problem is established. It is shown that the variational problem for the system of equations of two-speed hydrodynamics is well-posed in the corresponding Sobolev spac

About one mathematical model of swelling of the clay shay around cylindrical well

A thermodynamically mathematically matched model of the linear theory of poroelasticity is proposed for describing shale swelling with an aqueous electrolyte. In this case, it is assumed that shale behaves as an isotropic, ideal ionic membrane, and in this case, the swelling depends only on the full stress tensor and on the chemical potential of water in the pores of the rock. The diffusion equation for pressure was obtained from the equation of poroelasticity, in the presence of chemical effects. It is shown that the diffusion coefficient is inversely proportional to the porosity

Cauchy Problem for System of the Burgers Equations Arising in the Two-velocity Hydrodynamics

A system of the Burgers equations of the two-velocity hydrodynamics is derived. We consider the Cauchy problem in the case of a one-dimensional system and the estimate of the stability of the solution is obtained. We have obtained a formula for the Cauchy problem for the one-dimensional system of equations that arises in the two-velocity hydrodynamics. It is shown that with disappearance of the kinetic friction coefficient, which is responsible for the energy dissipation, this formula turns to the famous Cauchy problem for the one-dimensional Burgers equation

Simulation of linear asynchronous electric drive of slow-speed mechanisms of agricultural complex

Abstract The agro-industrial complex includes a system of enterprises - the production of means of production for agricultural enterprises and various industries, as well as the sphere of processing, transportation and marketing of raw materials and finished products. The development of rational electric drives corresponding to the drive characteristics of production machines solves the problem of energy and resource saving. The methods are determined by the tasks to be solved in the study of an asynchronous electric drive motor.</jats:p

Electromagnetic quality of a linear asynchronous motor with different designs of the secondary element

Linear asynchronous electric motors drive the working bodies of the mechanisms directly and quite fully fulfill their drive characteristics, allow eliminating mechanical converters and increase performance. This solves the problem of maximum articulation, splicing of a source of mechanical energy - an electric motor and an executive technological mechanism. Linear electric motors with a massive ferromagnetic secondary are the most cost-effective, taking into account the operating modes - when operating in starting modes and on stop, therefore, in practice, it often becomes necessary to calculate them in a short circuit mode. With a simplified calculation, it is convenient to use correction factors for increasing magnetic fluxes in the yoke, secondary losses and efforts of linear induction motors compared to the same values in a circular analogue. The dependences of such coefficients on the quality factor, the number of pairs of poles and the relative magnetic resistance of shunting. In the general case, the comparison and selection of the design of a linear induction motor is carried out at the stage of preliminary design using the optimality criteria - the quality factor