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Magnetohydrodynamics angular regular sensor (MHD ARS) has been used in many applications for its low noise in wide bandwidth, impact resistance and low power consumption; however, it is unable to estimate the angular velocity at low frequencies such as below 1 Hz. It is difficult to design compensation methods without an exact model. The aim of this study is to investigate a more exact analytical model characterization of the sensor’s frequency response, especially at a low-frequency zone.

A correction coefficient of electromagnetic force in simplified MHD ARS model was introduced according to the theoretical analysis of MHD flow and it was obtained by numerical simulation of electromagnetic force varying with time, space structure and frequency.

To make comparison, the transfer function of the designed MHD ARS in the experiment was identified using Gauss–Newton method with reasonable weights. The identification results confirmed the analytical model. Furthermore, a digital filter was designed based on the analytical model, and the compensation results showed that the frequency limit at low-frequency side was extended from 1 to 0.01 Hz.

The modified analytical model can describe the MHD ARS’s frequency response exactly and may be applied in its low-frequency compensation.

This paper aims to demonstrate the impact of interstellar (IS) magnetic field on stellar shocks existence, shape and size in the stellar wind (SW) vs interstellar medium (ISM) numerical models.

Comparison of hydrodynamics (HD) and magnetohydrodynamic (MHD) models results with or without ISM magnetic field, its intensity and ISM parameters.

ISM magnetic field facilitates formation and stabilises bow shocks around all astrophysical objects. ISM magnetic field may also be one of the reasons for a bow shock existence around the Sun.

ISM magnetic field should be implemented in MHD and future kinetic numerical models of the SW interaction with ISM plasma.

This paper presents the results of HD and MHD models of bow shocks and the importance of ISM magnetic field implementation, according to astronomical bow shock observations. The study also presents a review of the most important papers showing the numerical results of bow shock formation.

The purpose of this paper is to investigate a reliable evaluator of arc re-ignition and to develop a numerical tool for accurate prediction of arc behaviour of low-voltage switching devices (LVSDs) prior to empirical laboratory testing of real products.

Two types of interruption tests have been carried out in the investigation of re-ignition evaluators. Arc modelling tool coupled with the load circuit has been developed to predict arc characteristics based on conventional magnetohydrodynamics theory, with special attention given to Lorentz force acting on the arc column and surface phenomena on the splitter plate. The model assumptions have been validated by experimental observation of arc motion and current and voltage waveforms.

It is found that the exit-voltage across the switching device and the ratio of system to exit-voltage at the current zero point are reliable evaluators for prediction of re-ignition. Where the voltage ratio is positive, instantaneous re-ignition does not occur. Further, the probability of re-ignition is very low if the voltage ratio is in the rage of −1.3 to 0.

It is observed that the voltage ratio can be considered as a reliable global evaluator of re-ignition, which can be used for various types of LVSD test conditions. In addition, it is shown that arc modelling allows a good prediction of the current and voltage waveforms, arc motion as well as the exit-voltage, which can be used to obtain the evaluator of re-ignition.

The purpose of the paper is to give a brief description of the new topic introduced for the first time at the EASN Conferences.

The topic concerns the heliosphere, the nearest surrounding of the Sun and thus the nearest vicinity of the Earth. The heliosphere is created due to the interaction between the solar wind and the local interstellar medium.

This paper does not include any new information about the heliosphere and only introduces a new topic to this journal. It is briefly shown how heliospheric structures are formed, what factors affect a shape of the heliosphere, what measurements are made by Ulysses, Voyager and IBEX space missions (important for the heliosphere modeling) and how obtained data are used to validate theoretical results.

To categorize the paper under one of these classifications, research paper, viewpoint, technical paper, conceptual paper, case study, literature review or general review, the authors chose a paper type, general review, as the closest category to this paper. However, it is not a purpose of this paper to provide an extensive review of the community efforts to investigate the physical processes in the vicinity of the heliosphere interface. This is mostly a status report.

As the new topic in this journal, the article introduces in detail only a small number of aspects connected with heliosphere models. Interplanetary and interstellar magnetic field structures are primarily described. Other factors are only mentioned.

An electrospinning process is a multi-phase and multi-physics process. The purpose of this paper is to numerically simulate the two-phase flow in the electrospinning process. The numerical results can offer in-depth insight into physical understanding of many complex phenomena which cannot be fully explained experimentally.

The two-phase flow can be calculated by solving the modified Navier-Stokes equations under the influence of electric field and the interface between the two fluids has been determined by using the Volume of Fluids (VOF) method. A realizable k-e model is used to model the turbulent viscosity. The numerical results can be obtained using Computational Fluid Dynamics (CFD) techniques.

The numerical simulation is a powerful tool to controlling over electrospinning parameters such as voltage, flow rate, and others.

The numerical simulation of two-phase flow model will take into account solvent evaporation and solidification of the jet, which play pivotal roles in determining the internal fiber morphology of the jet to be described here.

This paper deals with studying numerically the two-phase flow in the electrospinning process by applying CFD techniques. And the flow is modeled by ANSYS(FLUENT) using the VOF model.

Caring for a person with a substance use disorder (SUD) and/or mental health disorder (MHD) represents a significant burden for family members. The features of “carers/family members” experiences reflect trauma signatures. Consequently, working through this trauma for carers corresponds with psychological recovery, empowerment processes and intrapersonal/interpersonal needs. The purpose of this paper is to outline a framework called the “personal and relational empowerment (PRE)” framework which enables family support practitioners to help family members to be able to take control of their own lives, develop meaningful relationships and live purposeful and fulfilling lives, regardless of whether the person with the SUD and/or MHD is in recovery or not.

This paper critically reviews existing frameworks for carer recovery, through a systematic literature search, and proposes a “PRE” alternative to redress the shortfalls in these existing frameworks.

The PRE framework takes a multi-level needs-based approach to understand carer recovery. This framework links the concepts – psychological recovery, empowerment processes and intrapersonal/interpersonal needs.

The PRE framework recognises the importance of recovery support practitioners being able to balance the immediate carer crisis intervention needs responses with personal growth and well-being supporting interventions.

The PRE framework of family recovery attempts to answer the need to broaden the focus on the family journey to better reflect the principles and practices of contemporary SUD and/or MHD recovery-based support.

The evaluations of the magnetohydrodynamics angular rate sensor (MHD ARS) in its applications necessitate further improvements in the sensor’s dynamic measurement ability. The magnetic field of the MHD ARS is a key factor in the sensor’s modeling and error analysis. The aim of this study is to illustrate the influence of a non-uniform magnetic field on the sensor.

Numerical simulation is made using ANSYS FLUNET with the magnetic field calculated by 3D-Magnetostatic. The comparison of the simulation results between uniform and non-uniform magnetic fields is made to reveal and explain the effects of magnetic field inhomogeneity (MFI) on the flow and electric field in detail. Two different structures with different MFIs are designed to confirm the MFI effect on the sensor’s output in simulation and experiment. A cross-correlation experiment and an adaptive filter are carried out to extract the signal to identify the error of the sensor output caused by MFI.

The MFI effect on the flow field in MHD ARS is found to be insignificant, while its effect on the electric potential is considerable. The comparisons between two kinds of MHD ARS in numerical simulation and experiment show that the MFI effect on the sensor error can be identified by fitting the sensor output. The deviation is mainly generated at the peaks and valleys of an angular vibration.

The study of the MHD ARS under the influence of a non-uniform magnetic field can offer an understanding of the MFI effect on the sensor and an evaluation method of the sensor error caused by the MFI effect.

This paper aims to address the performance of different subgrid-scale models (SGS) for hydro- (HD) and magnetohydrodynamic (MHD) channel flows within a collocated finite-volume scheme.

First, the SGS energy transfer is analyzed by a priori tests using fully resolved DNS data. Here, the focus lies on the influence of the magnetic field on the SGS energy transport. Second, the authors performed a series of 18 a posteriori model tests, using different grid resolutions and SGS models for HD and MHD channel flows.

From the a priori analysis, the authors observe a quantitative reduction of the SGS energy transport because of the action of the magnetic field depending on its orientation. The a posteriori model tests show a clear improvement because of the use of mixed-models within the numerical scheme.

This study demonstrates the necessity of improved SGS modeling strategies for magnetohydrodynamic channel flows within a collocated finite-volume scheme.

The purpose of this paper is to review previous research studies on mathematical models for entropy generation in the magnetohydrodynamics (MHD) flow of nanofluids. In addition, the influence of various parameters on the velocity profiles, temperature profiles and entropy generation was studied. Furthermore, the numerical methods used to solve the model equations were summarized. The underlying purpose was to understand the research gap and develop a research agenda.

This paper reviews 141 journal articles published between 2010 and 2022 on topics related to mathematical models used to assess the impacts of various parameters on the entropy generation, heat transfer and velocity of the MHD flow of nanofluids.

This review clarifies the application of entropy generation mathematical models, identifies areas for future research and provides necessary information for future research in the development of efficient thermodynamic systems. It is hoped that this review paper can provide a basis for further research on the irreversibility of nanofluids flowing through different channels in the development of efficient thermodynamic systems.

Entropy generation analysis and minimization constitute effective approaches for improving the performance of thermodynamic systems. A comprehensive review of the effects of various parameters on entropy generation was performed in this study.

The purpose of current flow configuration is to spotlights the thermophysical aspects of magnetohydrodynamics (MHD) viscoinelastic fluid flow over a stretching surface.

The fluid momentum problem is mathematically formulated by using the Prandtl–Eyring constitutive law. Also, the non-Fourier heat flux model is considered to disclose the heat transfer characteristics. The governing problem contains the nonlinear partial differential equations with appropriate boundary conditions. To facilitate the computation process, the governing problem is transmuted into dimensionless form via appropriate group of scaling transforms. The numerical technique shooting method is used to solve dimensionless boundary value problem.

The expressions for dimensionless velocity and temperature are found and investigated under different parametric conditions. The important features of fluid flow near the wall, i.e. wall friction factor and wall heat flux, are deliberated by altering the pertinent parameters. The impacts of governing parameters are highlighted in graphical as well as tabular manner against focused physical quantities (velocity, temperature, wall friction factor and wall heat flux). A comparison is presented to justify the computed results, it can be noticed that present results have quite resemblance with previous literature which led to confidence on the present computations.

The computed results are quite useful for researchers working in theoretical physics. Additionally, computed results are very useful in industry and daily-use processes.