Variable Magnetic Field Research Articles

A novel formula for calculating repulsive forces in horizontally aligned nonferrous cylindrical particles within an Eddy current separator

Eddy Current Separation (ECS) stands as a highly efficient recycling technology crucial for separating nonferrous particles from waste electrical and electronic equipment (WEEE). This process relies on repulsive forces induced by eddy currents as particles traverse the variable magnetic field of a rotating magnetic drum. Achieving optimal separation in this multifaceted process demands a careful selection of magnetic drum parameters. This study focuses on modeling the repulsive forces acting on diverse nonferrous particle shapes, with a particular emphasis on horizontally oriented cylindrical particles, and exploring their trajectories under various adjustable parameters. The effectiveness of the separator is intimately governed by these repellent magnetic forces. Our numerical model comprehensively accounts for the key magnetic and mechanical forces shaping particle movement. Through a dedicated Matlab program, simulations of trajectories are conducted, dissecting the influence of parameters such as separation angle, number of poles, electromagnetic drum velocity, and particle sizes. The findings, elucidated in detailed diagrams, offer a profound understanding of each parameter's impact, crucial for optimizing ECS processes.

Citizen science: Development of a low-cost magnetometer system for a coordinated space weather monitoring

As part of Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS) project, a low-cost, commercial off-the-shelf magnetometer has been developed to provide quantitative and qualitative measurements of the geospace environment from the ground for both scientific and operational purposes at a cost that will allow for crowd-sourced data contributions. The PSWS magnetometers employ a magneto-inductive sensor technology to record three-axis magnetic field variations with a field resolution of ∼3 nT at a 1 Hz sample rate. The measurement range of the sensor is ±1.1×106 nT) and is valid over a temperature range of −40 °C to +85 °C. Data from the PSWS network will combine these magnetometer measurements with high frequency (HF, 3–30 MHz) radio observations to monitor large-scale current systems and ionospheric disturbances due to drivers from both space and the atmosphere. A densely-spaced magnetometer array, once established, will demonstrate their space weather monitoring capability to an unprecedented spatial extent. Magnetic field data obtained by the magnetometers installed at various locations in the US are presented and compared with the existing magnetometers nearby, demonstrating that the performance is very adequate for scientific investigations.

Hydromagnetic Non-Newtonian Nanofluid Flow Past Linealy Stretching Convergent-Divergent Conduit with Chemical Reaction

This paper investigates hydromagnetic non-Newtonian nanofluid flow past linearly stretching convergent-divergent conduit with chemical reaction using spectral ralaxation method. The fluid considered here is electrically conducting and is subjected to a constant pressure gradient and variable magnetic field. The two non-parallel walls are assumed not to intersect and the angle between the inclined walls is <i>θ</i>. The governing equations are continuity equation, momentum equation, species concentration, induction equation and energy equation. On modelling, the resulting partial differential equations are non-linear and are first transformed into system of ordinary differential equations through similarity transformation. The resulting boundary value problem is solved numerically using Spectral Relaxation Method. The results obtained after varying Hartman number, Unsteadiness parameter, Reynolds number, Solutal and Thermal Grashof number on velocity, concentration, temperature and induction profiles are represented in form of graphs. Some of the application of this study are, when extracting the energy from earth crust that varies in length between five to ten kilometres and temperature in between 500° and 1000°, nano-fluids are employed to cool the machinery and equipment working under high friction and high temperature. This present study considers nanofluid acting as a coolant of such equipment as well as acting as a lubricant thus reducing the rate of wear and tear of the equipment. The copper-water increases the thermophysical properties thus increasing heat transfer coefficient and hence increasing cooling rate.

Full-Wave Simulation of a Helmholtz Radiofrequency Coil for Magnetic Resonance Applications

Magnetic resonance imaging (MRI) is a non-invasive diagnostic technique able to provide information about the anatomical, structural, and functional properties of different organs. A magnetic resonance (MR) scanner employs radiofrequency (RF) coils to generate a magnetic field to excite the nuclei in the sample (transmit coil) and pick up the signals emitted by the nuclei (receive coil). To avoid trial-and-error approaches and optimize the RF coil performance for a given application, accurate design and simulation processes must be performed. We describe the full-wave simulation of a Helmholtz coil for high-field MRI performed with the finite-difference time-domain (FDTD) method, investigating magnetic field pattern differences between loaded and unloaded conditions. Moreover, the self-inductance of the single loops constituting the Helmholtz coil was estimated, as well as the frequency splitting between loops due to inductive coupling and the sample-induced resistance. The result accuracy was verified with data acquired with a Helmholtz prototype for small phantom experiments with a 3T MR clinical scanner. Finally, the magnetic field variations and coil detuning after the insertion of the RF shield were evaluated.

Helioseismic Properties of Dynamo Waves in the Variation of Solar Differential Rotation

Solar differential rotation exhibits a prominent feature: its cyclic variations over the solar cycle, referred to as zonal flows or torsional oscillations, are observed throughout the convection zone. Given the challenge of measuring magnetic fields in subsurface layers, understanding deep torsional oscillations becomes pivotal in deciphering the underlying solar dynamo mechanism. In this study, we address the critical question of identifying specific signatures within helioseismic frequency-splitting data associated with the torsional oscillations. To achieve this, a comprehensive forward modeling approach is employed to simulate the helioseismic data for a dynamo model that, to some extent, reproduces solar-cycle variations of magnetic fields and flows. We provide a comprehensive derivation of the forward modeling process utilizing generalized spherical harmonics, as it involves intricate algebraic computations. All estimated frequency-splitting coefficients from the model display an 11 yr periodicity. Using the simulated splitting coefficients and realistic noise, we show that it is possible to identify the dynamo wave signal present in the solar zonal flow from the tachocline to the solar surface. By analyzing observed data, we find similar dynamo wave patterns in the observational data from the Michelson Doppler Imager, Helioseismic Magnetic Imager, and Global Oscillation Network Group. This validates the earlier detection of dynamo waves and holds potential implications for the solar dynamo theory models.

Magnetic Field Mapping-Based Battery Management System (BMS) for Lead Acid Application

Lead Acid Batteries (LAB) are a widely used technology in Energy Storage Systems (ESS) due to their abundant and low-cost materials, non-flammable water-based electrolyte, and high recyclability rate. The main applications for LABs are in mobility, data centers, and telecommunications. According to the Consortium of Battery Innovation (CBI), the market for lead acid batteries is projected to increase 150 GWh between 2025 and 2030. Therefore, it is fundamental to identify emerging failure modes in LABs in ESS systems to reduce battery degradation and to extend the use life.An important failure mode in flooded LABs is acid stratification. This research explores H+ concentration changes in H2SO4 (sulfuric acid) electrolyte as a correlation of acid stratification. The objective is to develop a non-invasive, non-destructive, and accurate real-time battery monitoring system. The Magnetic Field Probing (MFP) technique, popular in the medical imaging field, shows a promising solution for ESS performance evaluation. This technique can measure induced magnetic field changes based on variation in H+ concentration in the cell during cycling. See Figure. 1 (a). MFP provides early onset notification of stratification in flooded LABs with capability to discern other failure modes in non-flooded lead batteries.A set of experimental trials measured pH and magnetic field variation of H2SO4 electrolyte. See Figure. 1 (a). The preliminary results demonstrated changes in electrolyte pH due to possible stratification. See Figure. 1 (b). A correlation between the output voltage resulting from the interaction of the induced magnetic field and the changes in the electrolyte concentration was found. See Figure 1(c) The optimal AC input frequency maximizes the induced magnetic field response. The value found for optimal AC input frequency was 32kHz, which depends on the physical properties of the magnetic field inductors (air core solenoid coils). The experimental results showed and concluded that the induced magnetic field across the tested cell is also inversely proportional to the distance between coils attached to the cell.Further research involves the use of magneto-resistors to establish a magnetic field mapping in lead acid cells as they are being cycled. Magnetic field response is measured while lead acid cells are cycled from 100% to 20% state of charge range. In the future, this study will provide insights and findings to model and predict cell stratification in lead acid cells with electrochemical computational simulations.Keywords: Energy storage systems, lead acid batteries, acid stratification, magnetic field, non-invasive method Figure 1

Analyzing the 3D-MHD flow of a sodium alginate-based nanofluid flow containing alumina nanoparticles over a bi-directional extending sheet using variable porous medium and slip conditions

Abstract The sodium alginate (SA)-based nanofluid flow comprising alumina nanoparticles on a bi-directional extending sheet has many applications, which include thermal management, automotive radiators, industrial heat exchangers, conductive coatings, flexible electronics, electromagnetic shielding, solar panels, etc. A numerical study based on the SA-based nanofluid flow containing alumina nanoparticles over a bi-directional extending sheet in the presence of variable Darcy porous media has not yet been examined. Therefore, this study focuses on numerically investigating the flow behavior of a nanofluid of SA containing nanoparticles of alumina (Al2O3) over a bi-directional extending sheet. The variable Darcy porous media, magnetic field, thermal radiation, and thermal-dependent and space-dependent heat sources are applied to examine heat transfer flow. The velocity and thermal slip conditions have been used in the present model. The model is first shown as partial differential equations and is then converted to ordinary differential equations (ODEs). A numerical technique called bvp4c MATLAB function is applied to solve the modeled ODEs. The model is validated with previously published results. From the obtained results, it is found that high magnetic factor increases the thermal distribution, skin frictions, and heat transfer rate and reduces the velocity profiles along both directions. The Casson factor reduces the skin friction, heat transfer rate, and velocity profiles along both directions while increasing the thermal distribution. High velocities and temperature distributions of a SA-based nanofluid flow containing alumina nanoparticles are found for the scenario of no-slip condition when matched to the slip condition. It is concluded from the observed results that the percentage increase is higher for the no-slip conditions compared to the slip conditions.

Visual inertial localization method assisted by pedestrian motion features

Visual-inertial SLAM (Simultaneous Localization and Mapping) is a reliable and effective positioning method in indoor and outdoor environments. However, low-cost sensors and extreme environments (such as low light and weak textures) severely impact the nonlinear optimization within the sliding window, loop closure detection, and graph optimization. To address this, the Pedestrian Dead Reckoning (PDR) algorithm, capable of providing robust pose estimation over a certain time period, is introduced as an auxiliary to enhance overall performance. However, its heading is susceptible to inaccurate readings due to variations in magnetic field anomalies.The paper proposes integrating the velocity, attitude, and stride information provided by PDR into the visual-inertial SLAM optimization, which can improve the localization accuracy by 60%. In extreme scenarios, incorporating the PDR pose information into loop closure detection and graph optimization can improve the localization accuracy by over 30%. Furthermore, utilizing the heading information from visual-inertial SLAM to correct the PDR heading offset caused by magnetic anomalies can improve the localization accuracy by over 20%.

In-situ magnetic fields monitoring and compensation for zero-field atomic magnetometers

Zero-field atomic magnetometers (AMs) offer high sensitivity in compact size, making them versatile for various applications. However, magnetic field variations within shielded environments, especially in challenging conditions, can disrupt the zero-field, exceeding the AM’s linear range and reducing its accuracy and sensitivity. Conventional solutions rely on auxiliary sensors or an in-situ close-loop mode, leading to increased financial and spatial costs or interference among sensors. This study proposes an in-situ monitoring and compensation method, thereby establishing a monitoring-compensation loop mode for zero-field AMs without additional sensors. The proposed mode enhances conventional AMs by integrating not only the first but also the second harmonic of the longitudinal polarization, enabling real-time monitoring and rapid online compensation of triaxial magnetic fields. The high sensitivity is maintained and sensor interference is suppressed as AMs operate similarly to conventional ones near the zero-field. When field variations arise, rapid online compensation is triggered to restore the zero-field, covering a range of up to 120 nT with an accuracy of 8pT. Particularly, artificial intelligence algorithms are introduced to achieve simultaneous triaxial online compensation, enhancing the efficiency. This study supports the cost-effective and highly sensitive use of zero-field AMs in space-limited or challenging magnetic environments.

ОБЛАДНАННЯ ВХІДНОЇ МАГНІТНО-КАВІТАЦІЙНОЇ ПІДГОТОВКИ ВОДИ ДЛЯ ТЕПЛОМЕРЕЖ

If high-quality water treatment for boilers is not organized, the impurities present in untreated water lead to a number of problems: large colloidal and mechanical impurities in the form of scale, rust, clay or sand quickly clog the pipes, significantly reducing their internal diameter. This causes the failure of shut-off valves and pumping equipment: hardness salts and other poorly soluble salts (carbonates, magnesium and calcium sulfates, silicates, various compounds of copper and manganese) settle, creating a crust on the metal walls of the equipment, which reduces its heat output. This contributes to a reduction in boiler power, increases energy costs, and significantly shortens the life of the equipment. Based on the analysis of the latest research, it is proposed to improve the quality and composition of water that comes from municipal water supply, artesian wells and reservoirs, before filtering and deaerating water, it is proposed to pre-treat it with hydrocavitation and a magnetic field in order to soften and change its properties. The essence of the operation of the proposed equipment is that the effect of sound hydrocavitation and a variable magnetic field on water is reduced to a single process - the splitting of water molecules in the cavitation cavity into active radicals. The essence of various processes, namely hydrocavitation and magnetic influence on the passage of chemical reactions, breaking of hydrogen bonds in water molecules, is considered. The design of the equipment for the incoming magnetic cavitation preparation of water with an additional hydrocavitation effect on water during the reciprocating movement of the liquid through the nozzle is proposed, which combines the effects of breaking hydrogen bonds in water molecules, oxidation of iron and calcium ions, increasing the Рn indicator, and after its after settling, it is fed to the ion exchange and deaeration units, and later to the heating mains.

Probing intrinsic magnetic domain in bare CrI3 bulk with a magnetic force microscope

Two-dimensional magnetism in CrI3 links to its stacking structural order. In bulk CrI3, coexistence of monoclinic and rhombohedral phases has been observed across wide temperature range. Direct characterization of the magnetic textures on the exposed surface of bulk CrI3 has been challenging but meaningful. Here, we have employed a custom glovebox-assisted magnetic force microscope to observe the evolution of magnetic domains on the bare CrI3 surface under variable temperatures and magnetic fields for the first time. Below the Curie temperature, robust parallel stripe magnetic domains spontaneously emerge. The root mean square values of the localized weak pinning domain images at various temperatures indicate a critical transition behavior consistent with 3D Ising model with Tc ∼ 59 K. Images obtained by varying the magnetic field at low temperatures, showing magnetization saturation-reentry cycles, reveal larger hysteresis and stronger disorder compared to the VSM measurement, indicating local structural phase inhomogeneity. ​Two in-plane stripe magnetic domains oriented locally at an angle of 51-degrees compete under an out-of-plane magnetic field, presumably due to different sliding orientations induced by the magnetic field during the transition from a monoclinic to a rhombohedral phase. This study provides an experimental reference for future spin density wave manipulation in CrI3.

Third-order nonlinear Hall effect in a quantum Hall system.

In two-dimensional systems, perpendicular magnetic fields can induce a bulk band gap and chiral edge states, which gives rise to the quantum Hall effect. The quantum Hall effect is characterized by zero longitudinal resistance (Rxx) and Hall resistance (Rxy) plateaus quantized to h/(υe2) in the linear response regime, where υ is the Landau level filling factor, e is the elementary charge and h is Planck's constant. Here we explore the nonlinear response of monolayer graphene when tuned to a quantum Hall state. We observe a third-order Hall effect that exhibits a nonzero voltage plateau scaling cubically with the probe current. By contrast, the third-order longitudinal voltage remains zero. The magnitude of the third-order response is insensitive to variations in magnetic field (down to ~5 T) and in temperature (up to ~60 K). Moreover, the third-order response emerges in graphene devices with a variety of geometries, different substrates and stacking configurations. We term the effect third-order nonlinear response of the quantum Hall state and propose that electron-electron interaction between the quantum Hall edge states is the origin of the nonlinear response of the quantum Hall state.

Stimuli-Responsive Liposomes of 5-Fluorouracil: Progressive Steps for Safe and Effective Treatment of Colorectal Cancer.

5-Fluorouracil (5-FU) has become one of the most widely employed antimetabolite chemotherapeutic agents in recent decades to treat various types of cancer. It is considered the standard first-line treatment for patients with metastatic colorectal cancer. Unfortunately, traditional chemotherapy with 5-FU presents many limitations, such as a short half-life, a low bioavailability, and a high cytotoxicity, affecting both tumor tissue and healthy tissue. In order to overcome the drawbacks of 5-FU and enhance its therapeutic effectiveness against colorectal cancer, many studies have focused on designing new delivery systems to successfully deliver 5-FU to tumor sites. Liposomes have gained attention as a well-accepted nanocarrier for several chemotherapeutic agents. These amphipathic spherical vesicles consist of one or more phospholipid bilayers, showing promise for the drug delivery of both hydrophobic and hydrophilic components in addition to distinctive properties, such as biodegradability, biocompatibility, a low toxicity, and non-immunogenicity. Recent progress in liposomes has mainly focused on chemical and structural modifications to specifically target and activate therapeutic actions against cancer within the proximity of tumors. This review provides a comprehensive overview of both internal-stimuli-responsive liposomes, such as those activated by enzymes or pH, and external-stimuli-responsive liposomes, such as those activated by the application of a magnetic field, light, or temperature variations, for the site-specific delivery of 5-FU in colorectal cancer therapy, along with the future perspectives of these smart-delivery liposomes in colorectal cancer. In addition, this review critically highlights recent innovations in the literature on various types of stimuli-responsive liposomal formulations designed to be applied either exogenously or endogenously and that have great potential in delivering 5-FU to colorectal cancer sites.

Detection of Underground Utility Pole Base for Distribution Transmission Network Based on Transient Electromagnetic Method

In the construction of overhead distribution network lines, ensuring the stability and construction quality of utility pole foundations is crucial. Traditionally, this process may involve excavation and direct inspection, which is not only time-consuming but may also cause environmental damage. The non-destructive detection scheme proposed in this paper, based on the transient electromagnetic method (TEM), offers an efficient and non-intrusive method for detecting the burial conditions of utility pole bases, pulls, and chucks. The transient electromagnetic method is a geophysical exploration technique that uses the principle of electromagnetic induction to detect the distribution of underground materials. When detecting utility pole bases, this method analyzes the electromagnetic response generated by underground metallic structures to obtain information. However, traditional TEM has a blind zone problem in shallow metal detection, which limits its application in utility pole base inspection. To address this issue, the scheme proposed in this paper introduces a decoupling coil to eliminate interference caused by the primary magnetic field. This decoupling technology significantly improves the detection discrimination, allowing for a more accurate determination of the burial depth and condition of bases, pulls, and chucks. Finite element numerical analysis using COMSOL 5.4 is adopted to examine the underground magnetic field distribution and optimize coil parameters. This analysis helps to understand the interaction between the electromagnetic field and underground structures, guiding the design of coils and the development of detection strategies. The prototype experimental platform built further validates the effectiveness of the scheme. Experimental results include measured data of magnetic field variations, assessments of detection depth and resolution. These experimental results are crucial for verifying the practical application potential of the non-destructive detection scheme.

Influence of rotating magnetic field on thermal field and entropy generation of a tube containing the nanofluid using mixture model

The thermo-fluidic properties and entropy generation in a tube comprising nanofluid under variable rotational magnetic field have not been studied earlier. In the current study, the influence of a rotating magnetic field is evaluated by using mixture model at four different pump power for three cases. A steady-state, Newtonian Ag/water nanofluid, incompressible, and 3D model have been supposed. The influence of pump power variation and using nanofluid are studied. Results indicated that by raising the pump power for three cases, the Nusselt number enhances, and Bejan number, the friction factor, and dimensionless temperature decreases. The rotating magnetic field for the Case III in comparison to the Case Ⅰ and Case Ⅱ at 60 W and 0.5 % volume fraction of nanofluid, enhanced the Nusselt number by 356.3 % and 12.42 %, respectively. In the presence of 0.5 % nanofluid at 60 W pump power, the friction factor increases by 103.5 % compared to Case Ⅰ, with the same fluctuations observed in Cases Ⅱ and Ⅲ. The maximum dimensionless temperature reached 0.575 for Case Ⅲ at a power of 30 W using water. A rotating magnetic field of 60 W raised PEC by 219.44 % and 261.11 % for Cases Ⅱ and Ⅲ, respectively, compared to Case Ⅰ.

Impact of dimensionality on the magnetocaloric effect in two-dimensional magnets

Magnetocaloric materials, which exploit reversible temperature changes induced by magnetic field variations, are promising for advancing energy-efficient cooling technologies. The potential integration of two-dimensional materials into magnetocaloric systems represents an emerging opportunity to enhance the magnetocaloric cooling efficiency. In this study, we use atomistic spin dynamics simulations based on first-principles parameters to systematically evaluate how magnetocaloric properties transition from three-dimensional (3D) to two-dimensional (2D) ferromagnetic materials. We find that 2D features such as reduced Curie temperature, sharper magnetic transition, and higher magnetic susceptibility are beneficial for magnetocaloric applications, while the relatively higher lattice heat capacity in 2D can compromise achievable adiabatic temperature changes. We further propose GdSi2 as a promising 2D magnetocaloric material. Our calculation predicts that GdSi2 exhibits an isothermal entropy change ΔSM of 22.5 J kg−1 K−1 and an adiabatic temperature change ΔTad of 6.2 K, near the hydrogen liquefaction temperature (TC≈25 K). Our analysis offers valuable theoretical insights into the magnetocaloric effect in 2D ferromagnets and demonstrates that 2D ferromagnets hold promise for cooling and thermal management applications in compact and miniaturized nanodevices.

Long-term Variation of the Solar Polar Magnetic Fields at Different Latitudes

The polar magnetic fields of the Sun play an important role in governing solar activity and powering fast solar wind. However, because our view of the Sun is limited in the ecliptic plane, the polar regions remain largely uncharted. Using the high spatial resolution and polarimetric precision vector magnetograms observed by Hinode from 2012 to 2021, we investigate the long-term variation of the magnetic fields in polar caps at different latitudes. The Hinode magnetic measurements show that the polarity reversal processes in the north and south polar caps are non-simultaneous. The variation of the averaged radial magnetic flux density reveals that, in each polar cap, the polarity reversal is completed successively from the 70° latitude to the pole, reflecting a poleward magnetic flux migration therein. These results clarify the polar magnetic polarity reversal process at different latitudes.

Similarity solution for the magnetogasdynamic shock wave in a self-gravitating and rotating ideal gas under the influence of radiation heat flux

The Lie invariance method is used to analyze the one-dimensional, unsteady flow of a cylindrical shock wave in a rotating, self-gravitating, radiating ideal gas under the influence of an axial or azimuthal magnetic field, with an emphasis on adiabatic conditions. The analysis assumes a stationary environment just ahead of the shock wave and considers variations in fluid velocity, magnetic field, and density within the perturbed medium just behind the shock front. In the governing equations, the impact of thermal radiation under an optically thin limit is integrated into the energy equation. Utilizing the Lie invariance method, the set of partial differential equations governing the flow in this medium is transformed into a system of nonlinear ordinary differential equations (ODEs) using similarity variables. Two distinct cases of similarity solutions are obtained by selecting different values for the arbitrary constants associated with the generators. Among these cases, one yields similarity solutions assuming a power-law shock path and the other an exponential-law shock path. For both cases, the resulting set of nonlinear ODEs are numerically solved using the 4th-order Runge–Kutta method in MATLAB software. The article thoroughly explores the influence of various parameters, including γ (adiabatic index of the gas), Ma−2 (Alfvén–Mach number), σ (ambient density exponent), l1 (rotational parameter), and G0 (gravitational parameter) on the flow properties. The findings are visually presented to offer a comprehensive insight into the effects of these parameters.

Local lattice distortions and electronic phases in perovskite manganite Pr0.5Sr0.5MnO3

We use variable temperature and magnetic field total x-ray scattering to study the crystal structure of the strongly correlated Pr0.5Sr0.5MnO3 perovskite, which is a paramagnetic insulator at room temperature, becomes a ferromagnetic metal at 272 K and, upon further decreasing the temperature, turns into an antiferromagnetic insulator at 105 K. We find that a model featuring a monoclinic symmetry captures the structure and its temperature and field evolution well, eliminating the need to evoke a phase segregation scenario as done in prior studies. It appears that coupled variations in Mn–oxygen bonding distances and angles from their values in an undistorted perovskite lattice, i.e., coupled local lattice distortions, assist the phase transitions in Pr0.5Sr0.5MnO3, contributing to its unique physical properties. Local structural distortions thus emerge as an important degree of freedom in strongly correlated systems, in particular perovskite manganates, and, therefore, they should be fully accounted for when their fascinating physics is considered.

Hydrodynamic mechanism for dynamical structure formation of a system of rotating particles

Based on the hydrodynamic mechanism, which takes into account the interaction of all particles, a numerical simulation of the formation of a dynamical structure in a viscous fluid was carried out. This structure is a result of the collective dynamics of rotating particles in the fluid. It is supposed that the particles have a magnetic moment and are driven into rotation by an external variable uniform magnetic field. The results of numerical modeling of collective dynamics are presented for three initial structures that can be formed by interacting dipole particles in the absence of an external magnetic field. Such equilibrium structures are a straight chain, a closed chain, and a periodic structure in the form of a flat system of particle chains. The rotation of particles sets the surrounding fluid in motion, whose flow creates hydrodynamic forces and moments that move the particles. The collective dynamics of a system of rotating particles leads to the formation of a new dynamical structure from the original one, and this new structure has its own characteristic features for each case considered. A qualitative comparison of the results of the dynamics for a particles’ system set in motion due to the action of an external moment or an external force is carried out. The proposed hydrodynamic mechanism for the formation of a dynamical structure as a result of the collective dynamics of a rotating particles’ system can be used to control structure formation in a liquid-particle system.