Plasma Flows in Solar Filaments as Electromagnetically Driven Vortical Flows

Electromagnetic expulsion acts on a body suspended in a conducting fluid or plasma, which is subject to the influence of electric and magnetic fields. Physically, the effect is a magnetohydrodynamic analogue of the buoyancy (Archimedean) force, which is caused by the nonequal electric conductivities inside and outside the body. It is suggested that electromagnetic expulsion can drive the observed plasma counter-streaming flows in solar filaments. Exact analytical solutions and scaling arguments for a characteristic plasma flow speed are reviewed, and their applicability in the limit of large magnetic Reynolds numbers, relevant in the solar corona, is discussed.

COMPUTER SIMULATION OF PARTICLE VELOCITY IN A CYCLONE

The article sets the goal of determining and calculating the speed of accelerated movement of particles in the gas-dust flow of an air cyclone, depending on the size of the cyclone, the physical properties of the particle and the gas-dust flow. A method for constructing a computer model of the motion of a particle in a roaring gas-dust flow of a cyclone is presented. The sequence of formalization of the computer model of the process of sedimentation of particles of a gas-dust flow of a cyclone unit is based on the theoretical foundations of aerodynamics and touches on the most significant aspects of the development of a cyclone. Attention paid to the analysis of the dynamics of particle motion in a centrifugal field, accelerated motion and a realistic estimate of the particle velocity. The mutual influences of five forces are considered. This is the centrifugal force, the force of resistance of the gas-dust flow, the forces of gravity, the Archimedean force and the force of inertia, acting on the accelerating motion of the particle in the flow. On the basis of the block principle, a general computer model of the cycloning process is built, which makes it possible to calculate the uneven velocity of a particle in a gas-dust flow. Analytical methods for evaluating the acceleration parameters and the main methods of numerical analysis of the dynamics of particle motion, shows that the main advantage of up to 0.8 seconds is the accelerated motion of a particle in a gas-dust flow under the given conditions. During this time, most of the particles reach the cyclone wall. This shows that the determination of the accelerating motion of a particle plays an important role in cyclones.

Numerical simulation of wave and wind effects on the anchoring system of a cage module for growing fish in marine areas

В представленной работе рассматриваются технические аспекты совершенствования конструкции садкового модуля для промышленного выращивания рыбы. Цель работы: уменьшение затрат на систему удержания положения садкового модуля на водоеме. Задача, которую необходимо решить для достижения данной цели заключается в разработке новой системы удержания садков с учетом их взаимодействия в едином модуле. Для решения данной задачи использован патентный поиск и анализ сильных и слабых сторон известных технических решений садков и их систем. Проанализированы недостатки так называемой «норвежской системы» удержания садковых модулей. Разработана система удержания садкового модуля, в которой не подразумевается использование круглозвенных цепей, а натяжение системы обеспечивается балансирами. Кроме того, в методику расчета введен учет вертикальной составляющей при расчете реакции опоры якоря, что позволило боле точно рассчитать необходимую массу якорей с учетом уменьшения силы трения и архимедовой силы. This paper discusses the technical aspects of improving the design of the cage module for industrial fish farming. Objective: to reduce the cost of the system for holding the position of the cage module on the reservoir. The task that needs to be solved to achieve this goal is to develop a new system for holding cages, taking into account their interaction in a single module. To solve this problem, we used patent search and analysis of the strengths and weaknesses of known technical solutions of cages and their systems. The disadvantages of the so-called "Norwegian system" for holding cage modules are analyzed. A system for holding the cage module has been developed, which does not imply the use of round-link chains, and the tension of the system is provided by balancers. In addition, the calculation method takes into account the vertical component when calculating the reaction of the anchor support, which made it possible to more accurately calculate the required mass of anchors, taking into account the reduction of the friction force and Archimedean force.

MATRIX CAGES HOLDING SYSTEM FOR INDUSTRIAL FISH FARMING

In the paper, the technical aspects of modeling the retention system of matrixtype cages for industrial fish farming in a pond is considered. To date, there is no developed calculation methodology that takes into account the layout features of each cage module. The layout of the modules can vary significantly: from 1 to 36 cages of various designs. The aim of the work is to substantiate the parameters of the holding ropes, the length of the pull chains and the required mass of anchors by calculating the tensile forces in the ropes and the reaction of the anchor supports when solving the dynamic task in an unsteady setting. To solve this problem, a dynamic system was developed considering wind, wave, and inertial loads acting on all elements of the system: cage, holding ropes, chains, anchors. The force acting on the surface of the cage from the wind is received. The values of tensile forces in the ropes, the reaction of the supports of the anchors in three planes are obtained. The lengths of the chains are identified, ensuring the absence of tearing forces acting on the anchors. The masses of anchors are calculated taking into account the Archimedean force, depending on the density of the anchors’ material. The simulation lasted for 60 s. At 37 seconds of calculation, a resonant phenomenon was revealed: a significant increase in the breaking strength in the rope.