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Flow structures beneath a moving disturbance along a water free surface in the weakly nonlinear weakly dispersive regime in a sheared channel with finite depth and constant vorticity are investigated. We compute the exact two branches of steady solutions in the disturbance moving frame. The velocity field in the bulk fluid is approximated which allows us to compute the flow structures beneath the free surface including stagnation points and Kelvin cat-eyes structures. We show that stagnation points exist only in one branch of solutions. The bifurcation of the flow is analyzed according to the intensity of the vorticity and the speed of the moving disturbance. Differently from the unforced problem, stagnation points can arise for small values of the vorticity as long as the moving disturbance travels sufficiently fast. [ABSTRACT FROM AUTHOR]

Understanding the navigation through semi-dense crowds at intersections poses a significant challenge in pedestrian dynamics, with implications for facility design and insights into emergent collective behavior. To tackle this problem, a system of cognitive active agents at a crowded three-way intersection is studied using Langevin simulations of intelligent active Brownian particles (iABPs) with directed visual perception (resulting in non-reciprocal interactions) and self-steering avoidance—without volume exclusion. We find that the emergent self-organization depends on agent maneuverability, goal fixation, and vision angle, and identify several forms of collective behavior, including localized flocking, jamming and percolation, and self-organized rotational flows. Additionally, we demonstrate that the motion of individual agents can be characterized by fractional Brownian motion and Lévy walk models across different parameter regimes. Moreover, despite the rich variety of collective behavior, the fundamental flow diagram shows a universal curve for different vision angles. Our research highlights the impact of collision avoidance, goal following, and vision angle on the individual and collective dynamics of interacting pedestrians. The study of self-organisation of pedestrian movement at crossing is important for the design of strategies facilitating pedestrian flow in crowded areas and the mitigation of crowd-related accidents. The authors study the motion of pedestrians using a model inspired from active matter systems finding interesting phases of three interacting streams of agents, including jamming, and the emergence of a vortex state. [ABSTRACT FROM AUTHOR]

There is a critical need to understand how aging visual systems contribute to age-related increases in vehicle accidents. We investigated the potential contribution of age-related detriments in steering based on optic flow, a source of information known to play a role in navigation control. Seventeen younger adults (mean age: 21.1 years) and thirteen older adults (mean age: 57.3 years) performed a virtual reality steering task. The virtual environment depicted movement at 19 m/s along a winding road. Participants were tasked with maintaining a central lane position while experiencing eight repetitions of each combination of optic flow density (low, medium, high), turn radius (35, 55, 75 m), and turn direction (left, right), presented in random order. All participants cut corners, but did so less on turns with rotational flow from distant landmarks and without proximal optic flow. We found no evidence of an interaction between age and optic flow density, although older adults cut corners more on all turns. An exploratory gaze analysis revealed no age-related differences in gaze behavior. The lack of age-related differences in steering or gaze behavior as a function of optic flow implies that processing of naturalistic optic flow stimuli when steering may be preserved with age. [ABSTRACT FROM AUTHOR]

The performance of three centrifugal pumps designed to operate at a rotational speed of 151.84 rad/s and flow rates of 1, 25, and 45 kg/s is being investigated for both water and non-Newtonian fluids at various rotational speeds and flow rates. The analyses are being conducted experimentally and numerically within the flow rate range of 0.25–55 kg/s and rotational speed values between 52.36 and 151.84 rad/s. Additionally, artificial neural networks (ANN) trained using experimental pump performance data are being tested with experimental and numerical values obtained at a new rotational speed of 130.9 rad/s. The non-Newtonian fluids being tested include CMC 0.2% and CMC 0.4%, comprising carboxy methyl cellulose (CMC) solution and water. The results indicate that the pump's performance when handling non-Newtonian fluids is significantly influenced by the pump's geometry, rotational speed, and flow rate. In design parameters, the head obtained with 0.2% CMC for pump 1 is 3.3% greater than that in water. For pump 2, the highest head is in water according to design parameters. Pump 3 exhibits the highest head at a CMC of 0.4 in design parameters, and this value is 0.81% higher than the value with water. Experimental and numerical results demonstrate good agreement, especially in design parameters. The head obtained from numerical analyses with the RNG k–ε turbulence model for pumps 1, 2, and 3 at design parameters is 3, 10, and 9.83 m, respectively. The corresponding experimental heads are 3, 10, and 9.84 m, respectively. However, discrepancies between these results increase with higher flow rates and the use of non-Newtonian fluids. The compatibility of ANN results with experimental results is better than with numerical results, particularly at higher flow rates than the design condition. Pump performance values estimated by ANNs are 2% lower than the experimental results. This study provides comprehensive experimental data on the use of non-Newtonian fluids in different centrifugal pumps, and it also offers important guidance for future research by comparing ANN and computational fluid dynamics. [ABSTRACT FROM AUTHOR]

In this paper, a parabolic trough solar collector with variable heat flux depending on various twisted tapes as a swirl generator with cerium oxide, copper oxide, and multi-walled carbon nanotubes nanofluids with different volume fractions is presented. First, the impact of different twisted tapes is discussed, and the next part analyzes the influence of different volume fractions of nanofluids on improving the outlet temperature and the heat transfer coefficient. Finally, the best volume fraction of these nanofluids is used to form the hybrid nanofluid, and its effect on the turbulence thermal efficiency is numerically assessed. The obtained outcomes indicate that using a quadruple twisted tape improves the rate of heat transfer because it induces more rotational flow compared to other cases. Moreover, hybrid nanofluids of cerium oxide/copper oxide with a 2% volume fraction demonstrated the most increased thermal efficiency. Furthermore, to facilitate a broader utilization of the results, a precise relationship for the pressure drop and heat transfer coefficient in relation to alterations in terms of geometry, fluid velocity, and thermophysical properties obtained through statistical analysis is provided. Additionally, the assessed parabolic trough solar collector and a water heater with a capacity of 18,000 kcal/h were compared to evaluate the reduction in greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

By considering the rotationality of shear flow, we distinguish between tube segments created by reptation before the inception of shear flow and those created during flow. Tube segments created before inception of shear flow experience both stretch and orientation, while tube segments created after inception of flow are not stretched, but are only aligned in the flow direction. Based on this idea, the Rotation Zero Stretch (RZS) model allows for a quantitative description of the start-up of shear flow and stress relaxation after step-shear strain experiments, in agreement with data of polystyrene long/short blends and corresponding polystyrene 3-arm star polymers investigated by Liu et al. (Polymer 2023, 281:126125), as well as the shear viscosity data of poly(propylene carbonate) melts reported by Yang et al. (Nihon Reoroji Gakkaishi 2022, 50:127–135). In the limit of steady-state shear flow, the RZS model converges to the Doi-Edwards IA model, which quantitatively describes the steady-state shear viscosity of linear polymer melts and long/short blends. The assumption of "non-stretching" of tube segments created during rotational flow is therefore in agreement with the available experimental evidence. Three-arm star polymers behave in a similar way as corresponding blends of long and short polymers confirming the solution effect of the short arm in asymmetric stars. The analysis of step-shear strain experiments reveals that stress relaxation is at first dominated by stretch relaxation, followed at times larger than the Rouse stretch relaxation time by relaxation of orientation as described by the damping function of the Doi-Edwards IA model. The RZS model does not require any nonlinear-viscoelastic parameter, but relies solely on the linear-viscoelastic relaxation modulus and the Rouse stretch relaxation time. [ABSTRACT FROM AUTHOR]

Objectives: Partial thrombosis of the false lumen (FL) in patients with chronic aortic dissection (AD) of the descending aorta has been associated with poor outcomes. Meanwhile, the fluid dynamic and biomechanical characteristics associated with partial thrombosis remain to be elucidated. This retrospective, single-center study tested the association between FL fluid dynamics and biomechanics and the presence and extent of FL thrombus. Methods: Patients with chronic non-thrombosed or partially thrombosed FLs in the descending aorta after an aortic dissection underwent computed tomography angiography, cardiovascular magnetic resonance (CMR) angiography, and a 4D flow CMR study. A comprehensive quantitative analysis was performed to test the association between FL thrombus presence and extent (percentage of FL with thrombus) and FL anatomy (diameter, entry tear location and size), fluid dynamics (inflow, rotational flow, wall shear stress, kinetic energy, and flow acceleration and stasis), and biomechanics (pulse wave velocity). Results: Sixty-eight patients were included. In multivariate logistic regression FL kinetic energy (p = 0.038) discriminated the 33 patients with partial FL thrombosis from the 35 patients with no thrombosis. Similarly, in separated multivariate linear correlations kinetic energy (p = 0.006) and FL inflow (p = 0.002) were independently related to the extent of the thrombus. FL vortexes, flow acceleration and stasis, wall shear stress, and pulse wave velocity showed limited associations with thrombus presence and extent. Conclusion: In patients with chronic descending aorta dissection, false lumen kinetic energy is related to the presence and extent of false lumen thrombus. Clinical relevance statement: In patients with chronic aortic dissection of the descending aorta, false lumen hemodynamic parameters are closely linked with the presence and extent of false lumen thrombosis, and these non-invasive measures might be important in patient management. Key Points: • Partial false lumen thrombosis has been associated with aortic growth in patients with chronic descending aortic dissection; therefore, the identification of prothrombotic flow conditions is desirable. • The presence of partial false lumen thrombosis as well as its extent was related with false lumen kinetic energy. • The assessment of false lumen hemodynamics may be important in the management of patients with chronic aortic dissection of the descending aorta. [ABSTRACT FROM AUTHOR]

Three-dimensional mathematical model was established to investigate the solidification behavior during the continuous casting of a round bloom with the diameter of 0.7 m, where a novel swirling flow submerged entry nozzle (SEN) combined with mold electromagnetic stirring (M-EMS) method was used. The results show that an impinging flow phenomenon, which was normally formed in conventional single-port SEN casting, was effectively eliminated by adopting the new method. Molten steel from the swirling flow SEN port uniformly moved to the solidification front, which improved the dissipation rate of molten steel super-heat. When the rotational direction of the swirling flow in SEN was in the same direction as M-EMS, the super-heat of molten steel in mold can be decreased by 5 K, compared to the use of a conventional SEN with M-EMS. As the current intensity decreased from 310 to 100 A, the super-heat of molten steel in the mold center region was reduced by 3 K. This is due to that the shielding effect of M-EMS on rotational flow momentum from the swirling flow SEN became weak as the stirring intensity decreased. In addition, molten steel temperature near the meniscus under the current intensity of 310 and 100 A was 1787 K and 1790 K, respectively. The solidified shell thickness obtained by using 100 A current intensity was about 1 × 10−3 m larger than that of 310 A current intensity. [ABSTRACT FROM AUTHOR]

Tunable Diode Laser Absorption Spectroscopy (TDLAS) measurements of nitric oxide (NO) using a Quantum Cascade Laser (QCL) in the vicinity of 5.26 μm were conducted in a hypervelocity flow generated in the Texas A&M Hypervelocity Expansion Tunnel (HXT). The nascent NO was produced downstream of symmetric Mach reflections generated in Mach 8.5 flows with stagnation enthalpies from 6.9 to 11.1 MJ/kg. Path-averaged flow parameters of rotational and vibrational temperatures and NO concentration at a measurement rate of 30 kHz were obtained. By probing the R-branch of the fundamental absorption band in NO, thermal nonequilibrium and NO concentration levels in the post-shock region were measured. Measurements are compared to equilibrium calculations. NO equilibrium values during the 1 ms test period differ from the experimental rotational and vibrational measurements across the same time period. The experimental measurements of the rotational temperature show a consistent value around 3000 K larger than the recovered vibrational temperature across any run. The NO concentrations in all runs are near to the reported equilibrium value; often beginning higher than, and over time decaying to, the equilibrium concentration value of the specific tunnel run. [ABSTRACT FROM AUTHOR]

We consider plane, steady, homogeneous, rotational shearing flows of a granular gas of identical, inelastic, frictionless spheres. We introduce the balance equation for the second moment of the particle velocity fluctuations, solve it in an approximate way for shearing flows with arbitrary amounts of rotation, and determine the stress tensor based on these solutions. We consider the stress determined in this way in the context of Material Frame Indifference. [ABSTRACT FROM AUTHOR]

A class of exact solutions to the Navier–Stokes equations for an axisymmetric rotational incompressible flow is obtained. Invariant manifolds of flows that are axisymmetric about a given axis in three-dimensional coordinate space are found, and the structure of solutions is described. It is established that typical invariant regions of such flows are figures of rotation homeomorphic to the torus, which form a topological stratification structure, for example, in a ball, cylinder, and general complexes made up of such figures. The results extend to similar solutions of the system of MHD equations and Maxwell's electrodynamic equations, which have analogous properties in . Examples are given of axisymmetric vorticity vector fields and topological stratifications they generate on manifolds in that are invariant under the dynamical systems specified by these fields. [ABSTRACT FROM AUTHOR]

The evolutions of small and large compressive pulses are studied in a two-phase flow of gas and dust particles with a variable azimuthal velocity. The method of relatively undistorted waves is used to study the mechanical pulses of different types in a rotational, axisymmetric dusty gas. The results obtained are compared with that of nonrotating medium. Asymptotic expansion procedure is used to discuss the nonlinear theory of geometrical acoustics. The influence of the solid particles and the rotational effect of the medium on the distortion are investigated. In a rotational flow it is observed that with the increase in the value of rotational parameter, the steepening of the pulses also increases. The presence of dust in the rotational flow delays the onset of shock formation thereby increasing the distance where the shock is formed first. The rotational and the dust parameters are observed to have the same effect on the shock strength. [ABSTRACT FROM AUTHOR]

This paper is concerned with the well-posedness theory and geometric property of steady two-dimensional incompressible jet flow with vorticity and gravity. The main results show that for given incoming mass flux and atmospheric pressure at outlet, there exists a unique incompressible jet flow issuing from a semi-infinitely long nozzle, and the free boundary initiates smoothly at the separation point. Moreover, we obtain the single intersection property of the free boundary by under-over theorem. As a consequence, the monotonicity of the free boundary will be established. [ABSTRACT FROM AUTHOR]

In order to solve the problem of gap flow field divergence and poor forming accuracy in the electrochemical machining (ECM) titanium alloy inner helix, the pull reverse flow and pull downstream cathode physical models as well as the simulation models of machining gap flow field are established respectively in this paper. Different inclination angles of the liquid supply hole effected on the pull downstream cathode rotational flow field uniformity were explored. The results showed that the gap flow field distribution of the pull downstream cathode is better than pull reverse flow cathode, and the distribution of the rotational flow field formed when the inclination angle of the liquid supply hole achieves 40° is relatively uniform. Under the condition of voltage 12 V, cathode feed speed 15 mm/min, composite electrolyte 3%NaCl + 10%NaNO3 + 6%NaClO3, electrolyte temperature 30 °C, and electrolyte inlet pressure 2 MPa, the 800-mm length of titanium alloy inner helix sample was machined stably and reliably by the pull downstream cathode structure, which surface roughness is Ra0.8 μm. [ABSTRACT FROM AUTHOR]

With the help of Clebsch's potentials, we propose a Bateman–Luke-type variational principle for a boundary- value problem with a free (unknown) interface between two ideal compressible barotropic fluids (liquid and gas) admitting rotational flows. [ABSTRACT FROM AUTHOR]

Aging impacts human observer's performance in a wide range of visual tasks and notably in motion discrimination. Despite numerous studies, we still poorly understand how optic flow processing is impacted in healthy older adults. Here, we estimated motion coherence thresholds in two groups of younger (age: 18–30, n = 42) and older (70–90, n = 42) adult participants for the three components of optic flow (translational, radial and rotational patterns). Stimuli were dynamic random-dot kinematograms (RDKs) projected on a large screen. Participants had to report their perceived direction of motion (leftward versus rightward for translational, inward versus outward for radial and clockwise versus anti-clockwise for rotational patterns). Stimuli had an average speed of 7°/s (additional recordings were performed at 14°/s) and were either presented full-field or in peripheral vision. Statistical analyses showed that thresholds in older adults were similar to those measured in younger participants for translational patterns, thresholds for radial patterns were significantly increased in our slowest condition and thresholds for rotational patterns were significantly decreased. Altogether, these findings support the idea that aging does not lead to a general decline in visual perception but rather has specific effects on the processing of each optic flow component. [ABSTRACT FROM AUTHOR]

Due to enhanced heat transfer rate, the nanofluid and hybrid nanofluids have significant industrial uses. The principal objective of this exploration is to investigate how thermal radiation influences the velocity and temperature profile. A water-based rotational nanofluid flow with constant angular speed Ω is considered for this comparative study. A similarity conversion is applied to change the appearing equations into ODEs. Three different nanoparticles i.e., copper, aluminum, and titanium oxide are used to prepare different nanofluids for comparison. The numerical and graphical outputs are gained by employing the bvp-4c procedure in MATLAB. The results for different constraints are represented through graphs and tables. Higher heat transmission rate and minimized skin friction are noted for triple nanoparticle nanofluid. Skin coefficients in the x-direction and y-direction have reduced by 50% in trihybrid nanofluid by keeping mixed convection levels between the range 3 < ϵ ≤ 11 . The heat transmission coefficient with raising the levels of thermal radiation between 0.5 < π ≤ 0.9 and Prandlt number 7 < Pr ≤ 11 has shown a 60% increase. [ABSTRACT FROM AUTHOR]

In vertical contact control (VCC), a microdroplet array selectively contacts with an opposite microdroplet array. Generally, VCC is useful for the dispenser mechanism based on solute diffusion between microdroplet pairs. However, sedimentation due to gravity can cause an inhomogeneous distribution of solutes in microdroplets. Therefore, it is necessary to enhance solute diffusion to achieve the accurate dispensing of a large quantity of solute in the direction opposite to that of gravity. Herein, we applied a rotational magnetic field to the microrotors in microdroplets to enhance the solute diffusion in microdroplets. Driven by microrotors, the rotational flow can generate a homogeneous distribution of solutes in microdroplets. We analyzed the diffusion dynamics of solutes using a phenomenological model, and the results showed that the rotation of microrotors can increase the diffusion constant of solutes. [ABSTRACT FROM AUTHOR]

A class of exact solutions to the Navier–Stokes equations for rotational incompressible flows is obtained. A three-parameter family of solutions in a ball, spherical layers, and the entire space is constructed. [ABSTRACT FROM AUTHOR]

Optical centrifuges are laser-based molecular traps that can rotationally accelerate molecules to energies rivalling or exceeding molecular bond energies. Here we report time and frequency-resolved ultrafast coherent Raman measurements of optically centrifuged CO2 at 380 Torr spun to energies beyond its bond dissociation energy of 5.5 eV (Jmax = 364, Erot = 6.14 eV, Erot/kB = 71, 200 K). The entire rotational ladder from J = 24 to J = 364 was resolved simultaneously which enabled a more accurate measurement of the centrifugal distortion constants for CO2. Remarkably, coherence transfer was directly observed, and time-resolved, during the field-free relaxation of the trap as rotational energy flowed into bending-mode vibrational excitation. Vibrationally excited CO2 (ν2 > 3) was observed in the time-resolved spectra to populate after 3 mean collision times as a result of rotational-to-vibrational (R-V) energy transfer. Trajectory simulations show an optimal range of J for R-V energy transfer. Dephasing rates for molecules rotating up to 5.5 times during one collision were quantified. Very slow decays of the vibrational hot band rotational coherences suggest that they are sustained by coherence transfer and line mixing. In this work the authors use coherent anti-Stokes Raman scattering to study collisional vibrational excitation in highly rotationally excited CO2 molecules prepared in an optical centrifuge. [ABSTRACT FROM AUTHOR]

The response characteristics of large-diameter monopiles under lateral loads obviously differ from those of traditional small-diameter piles. To investigate the failure mechanism and soil resistance of laterally-loaded large-diameter monopiles, a series of finite element analyses of monopiles in soft clay were conducted. From the analysis results, an additional rotational soil flow can be observed in the large-diameter soil-monopile system, but there is only a slight difference (approximately 2–6%) in the bearing capacity of monopiles when the p–y method is utilized with and without rotational soil flow. Consequently, the consideration of the wedge-full-flow mechanism is sufficiently accurate for the monopile design of offshore wind turbines. Moreover, the base shear force and bending moment have an important influence on the lateral behaviour of large-diameter monopiles, and ignoring these additional base resistance components can greatly underestimate (even up to − 30%) the lateral bearing capability and lateral stiffness of semi-rigid and rigid large-diameter monopiles. Modal analysis of the 5 MW wind turbine also shows that this ignorance can lead to an underestimation (nearly 13.0%) of the structure's natural frequency. To consider the contributions of the additional base resistances to the lateral stiffness and bearing capacity, we developed two new T–u and M–φ springs to expand the current p–y method. [ABSTRACT FROM AUTHOR]

A novel laboratory platform has been designed and built for the irradiation of a plasma crystal (PC) with an electron beam (e-beam) having an energy around 10 keV and a current of tens of milliamperes. The pulsed e-beam collimated to a few millimeter-size spot is aimed at a crystal made of dust particles levitated in a radio-frequency (RF) plasma. The platform consists of three vacuum chambers connected in-line, each with different utility: one for generating free electrons in a pulsed hollow-anode Penning discharge, another for the extraction and acceleration of electrons at ∼ 10 kV and for focusing the e-beam in the magnetic field of a pair of circular coils, and the last one for producing PCs above a RF-driven electrode. The main challenge is to obtain both a stable e-beam and PC by insuring appropriate gas pressures, given that the e-beam is formed in high vacuum ( ≲ 10 - 4 Torr), while the PC is produced at much higher pressures ( ≳ 10 - 1 Torr). The main diagnostics include a high speed camera, a Faraday cup and a Langmuir probe. Two applications concerned with the creation of a pair of dust flow vortices and the rotation of a PC by the drag force of the e-beam acting on the strongly coupled dust particles are presented. The dust flow can become turbulent as demonstrated by the energy spectrum, featuring vortices at different space scales. [ABSTRACT FROM AUTHOR]

The response characteristics of large-diameter monopiles under lateral loads greatly differ from those of traditional small-diameter piles. By means of transparent soil and centrifuge tests, as well as numerical analyses, the soil flow mechanism and lateral behavior of large-diameter monopiles in soft clay were investigated. The study result reveals that a rotational failure mechanism, different from wedge-full-flow mechanisms, exists in the large-diameter monopile–soil system. For stubby large-diameter monopiles, using the classic wedge-full-flow mechanisms can lead to an overestimation of lateral capability due to its absence in considering the rotational mechanism. In addition, the normalized p–y curves in the rotational soil flow zone are also observed to have larger initial stiffness and attain yield plateau earlier than those in wedge-full-flow zone. Differences in Np values among different centrifuge tests are partly attributed to the different means of obtaining the clay’s undrained shear strength. When the undrained strength from consolidated undrained triaxial tests is taken, consistent values of Np originating from different test results are observed. Finally, based on the results from centrifuge tests and well-calibrated numerical analyses, an empirical formulation of Np for large-diameter monopiles in soft clay is proposed. [ABSTRACT FROM AUTHOR]

The intrusion of sea saltwater has destructive effects on freshwater resources as well as hydraulic structures. The first disastrous effect is reducing the volume of available freshwater storage and reducing available surface water quality. Various methods are used to prevent salinity intrusion into upstream river. One of the applied systems in reducing salinity intrusion in the mouth of rivers and especially in the shipping locks is the air bubbles curtain. For proper use of the air bubbles curtain system, it is necessary to determine the effect of different parameters on its performance. Therefore, in the present study, the effect of seawater density and air bubbles discharge on the performance of the air bubbles curtain was studied using a numerical model. The results show that the air bubbles curtain can prevent salinity intrusion by forming a vertical flow. Indeed, the air bubbles curtain's proper performance depends on the air bubbles discharge and the difference between saltwater and freshwater density. In other words, an increase in the density of seawater raises the salinity intrusion force and thus leads to the formation of a clockwise rotational flow upstream of the air bubbles curtain, which in turn intensifies the salinity intrusion into upstream of the air bubbles curtain and reduces the efficiency of the air bubbles curtain. Increasing air bubbles discharge culminates in preventing saltwater intrusion, although there is an optimal discharge that discharges greater than it has insignificant effects on air bubbles curtain performance. [ABSTRACT FROM AUTHOR]

Biological microorganisms overcome the Brownian motion at low Reynolds numbers by utilizing symmetry-breaking mechanisms. Inspired by them, various microrobot locomotion methods have been developed at the microscale by breaking the hydrodynamic symmetry. Although the boundary effects have been extensively studied for microswimmers and employed for surface-rolling microrobots, the behavior of microrobots in the proximity of multiple wall-based "confinement" is yet to be elucidated. Here, we study the confinement effect on the motion of surface-rolling microrobots. Our experiments demonstrate that the locomotion efficiency of spherical microrollers drastically decreases in confined spaces due to out-of-plane rotational flows generated during locomotion. Hence, a slender microroller design, generating smaller rotational flows, is shown to outperform spherical microrollers in confined spaces. Our results elucidate the underlying physics of surface rolling-based locomotion in confined spaces and present a design strategy with optimal flow generation for efficient propulsion in such areas, including blood vessels and microchannels. The effect of geometrical confinement on the locomotion of microrobots is crucial to operating them in real-world applications. Bozuyuk et al. show that the locomotion efficiency of microrollers decreases in confined spaces at high rotation frequencies and propose a slender geometry to overcome this problem. [ABSTRACT FROM AUTHOR]

Three-dimensional computational fluid dynamics simulations were carried out to investigate the multiphase flow and heat transfer in a round mold, when using swirling flow generator (SFG) designs in a tundish. The results show that an impinging flow in the mold is significantly suppressed by using a SFG design, compared to when using a conventional tundish. This is due to the rotational flow momentum, which forces the steel to move toward the mold wall. When using SFG designs, the whole flow field shows periodic characteristics in transient simulations. At a given casting speed, the velocity fluctuation period and fluctuation range in the submerged entry nozzle depend on the SFG inlet area as well as the inlet velocity. As the inlet velocity increases from 0.185 to 0.37 m/s (inlet area decreases from 0.0048 to 0.0024 m2), the velocity fluctuation period decreases from 3 to 2 seconds and the fluctuation range increases from ± 10.5 to ± 18.2 pct. However, a symmetrical distribution of the flow field is obtained in the time-averaged results of 9 and 6 seconds intervals for SFG inlet velocities of 0.185 and 0.37 m/s, respectively. In addition, within one velocity fluctuation period, the time-averaged temperature field generally has a uniform distribution. As the SFG inlet velocity increases from 0.185 to 0.37 m/s, the steel super-heat further decreases in the mold and the temperature is increased by around 2 K near the meniscus. Finally, in the current mold with a diameter of only 150 mm, the removal ratio of inclusions to the mold top surface is low by using both SFG designs. The removal ratio of 10 μm spherical inclusions is 10 pct lower compared to when using a conventional tundish. [ABSTRACT FROM AUTHOR]

In the manufacturing process of polyvinyl chloride (PVC) tubes, the required thickness and weight depend on the extruder flow rate. The extruder setup can be very time-consuming and inefficient since it requires adjusting the screw rotational speed by trial and error, as the relation between the flow rate and the rotational speed is not known a priori. Furthermore, it is also affected by the material properties, the melt temperature, and the pressure drop in the die. Direct measuring the flow rate or the tube thickness would require expensive gravimetric dosers or X-ray systems, respectively. Therefore, a soft sensor was developed to monitor tube thickness and its weight per unit length. Two alternative approaches are proposed to predict the extruder flow rate under wall slip conditions: one is based on a developed analytical model and one on data-driven algorithms. Results show that machine learning regression models can achieve high predictive performance (a relative error of 1.2% using a support vector regressor). [ABSTRACT FROM AUTHOR]

Rheological modeling of special concretes such as ultra-high performance concretes (UHPCs), self-compacting concretes (SCCs), or environmentally friendly concretes with low clinker contents but containing many fine particles increases model complexity because high amounts of colloidal and fine particles and complex chemistry result in strongly non-Newtonian rheological behavior. Straight-forward viscoplastic rheological models such as the well-known Bingham- or Herschel-Bulkley approach do not fit the flow behavior on a large scale at and lead to boundary value problems in numerical flow simulations. Increased viscoelastic properties due to chemical admixtures are not described by pure viscoplasticity analysis methods. To fill this gap, our research presents viscoplastic and viscoelastic linear and non-linear rheological characterization methods for common and strongly non-Newtonian cement pastes and combines the methods for a comprehensive viscoelastoplastic modeling of cementitious building materials. We illustrate and discuss the benefits and boundaries of each measurement technique in dependence of cementitious paste complexity. Three solid volume fractions from ϕ = 0.45 to 0.55 and three different flowability ranges, adjusted through varying superplasticizer amounts, were investigated in respect of steady-state and transient yield stress, viscosity, and non-linear viscoelastic material properties. Our results reveal that with increasing solid volume fraction and polymer amount, viscoelastoplastic modeling describes rheological flow on a large flow scale more appropriately than common viscoplastic methods. The results show a new approach for a full quantitative and qualitative rheological classification of cementitious building materials and thus improve the understanding of densely packed colloidal cementitious suspensions. The findings serve as prospective guideline to model complex cementitious building materials both at low and high shear rates, and to find an appropriate rheological description at the boundaries of flow. [ABSTRACT FROM AUTHOR]

Electrochemical grinding (ECG) is processed by the combination of dissolution and grinding. It is very suitable for the processing of difficult-to-cut stainless steel, but its processing performance is restricted by the matching effect of dissolution and grinding. In this work, the processing of the torus surfaces of the stainless steel shaver cap was taken as the research object. A flow field model including the through-hole structure and the rotation of the grinding head was proposed to optimize the flow field distribution and promote the uniform dissolution of materials. The flow field simulation results showed that the rotational flow formed by the high-speed rotation prolonged the electrolyte flow path and was not conducive to the discharge of electrolytic products, and the reasonable selection of the diameter and distribution of the through-hole could reduce the velocity difference. The effects of rotational speed, feed rate, and inlet pressure on the flatness and surface roughness of the torus surfaces were experimentally investigated, and a better matching effect of dissolution and grinding was obtained. Moreover, the experimental results showed that the inner-jet ECG had a good prospect in the batch processing of high-hardness stainless steel parts. [ABSTRACT FROM AUTHOR]

Influences of dispersing hybrid nanoparticles and imposing permeable media on cooling performance of tube have been demonstrated in this investigation. The behavior of system with reporting entropy generation has been analyzed. To grow the rotational flow, turbulator within the test section has been mounted and pip experiences constant heat flux in this section. For simulating three dimensional laminar steady flow, finite volume method was operated and for applying porous terms, UDF according to Darcy model has been applied to enforce the source terms. Comparing the outputs with previous article proves the existence of good accommodation. Dispersing hybrid nano-powders, not only enhance the cooling rate but also decrease the total irreversibility of system. The heating term of Sgen is much greater than other components and it decreases about 7.72% when Da = 10, Re = 1e2. As Da goes up, the heating term augments around 8.11% while the frictional term declines around 28.34%. As speed of inlet augments, the amount of Sgen,th declines around 19%. [ABSTRACT FROM AUTHOR]

Intravascular ultrasound (IVUS) can provide useful information in patients undergoing complex percutaneous coronary intervention with rotational atherectomy (RA). The association between IVUS findings and slow flow following rotational atherectomy (RA) has not been investigated, although slow flow has been shown to be an unfavorable sign with worse outcomes. The aim of this study was to determine the IVUS-factors associated with slow flow just after RA. We retrospectively enrolled 290 lesions (5316 IVUS-frames) with RA, which were divided into the slow flow group (n = 43 with 1029 IVUS-frames) and the non-slow flow group (n = 247 with 4287 IVUS-frames) based on the presence of slow flow. Multivariate regression analysis assessed the IVUS-factors associated with slow flow. Slow flow was significantly associated with long lesion length, the maximum number of reverberations [odds ratio (OR) 1.49; 95% confidence interval (CI) 1.07–2.07, p = 0.02] and nearly circumferential calcification at minimal lumen area (MLA) (≥ 300°) (OR, 2.21; 95% CI 1.13–4.32; p = 0.02). According to the maximum number of reverberations, the incidence of slow flow was 2.2% (n = 0), 11.9% (n = 1), 19.5% (n = 2), 22.5% (n = 3), and 44.4% (n = 4). In conclusion, IVUS findings such as longer lesion length, the maximum number of reverberations, and the greater arc of calcification at MLA may predict slow flow after RA. The operators need to pay more attention to the presence of reverberations to enhance the procedure safety. [ABSTRACT FROM AUTHOR]

The Bateman–Luke-type variational formulation of the free-boundary "sloshing" problem is generalized to the case of irrotational flows and unprescribed tank motions, i.e., to the case where the motions both of the tank and of the liquid should be found simultaneously for a given set of external forces applied to fixed points of the rigid tank body. We prove that the variational equation corresponding to the formulated problem implies both the dynamic (force and moment) equations of the rigid body and the free-boundary problem that describes sloshing in terms of the Clebsch potentials. [ABSTRACT FROM AUTHOR]

Fluid flow and mixing phenomena were investigated in a cylindrical-shaped, mechanically agitated water model ladle (D = 0.30 m) both computationally and experimentally. Embodying the dynamic/sliding mesh approach in ANSYS Fluent (version 18.0), appropriate flow models were formulated via the realizable k–ε turbulence model as well as LES (large eddy simulation) and, based on this, flow and mixing times were predicted in the water model system as a function of impeller speed. In parallel, while distributions of axial and rotational components of flow at different locations in the system were mapped via a Laser Doppler Velocimeter (LDV), electrical conductivity measurement technique was adopted to determine 95 pct bulk mixing times experimentally. Reproducible measurements, obtained under different experimental conditions, were applied to directly assess the relative adequacy of the two flow calculation procedures. Comparison between numerical predictions and experimental measurements indicates that LES provides considerably more accurate estimates and thus outperforms the realizable k–ε turbulence model. In general, the realizable k–ε model is found to overestimate flow recirculation rate leading to expeditious mixing or shorter mixing times in the system. The implications of the present findings, with reference to industrial-scale simulation of mechanically agitated, high-temperature systems, such as the Kanabara (KR)™ reactor, are also briefly addressed in the text. [ABSTRACT FROM AUTHOR]

A liquid film that is under the action of two electric forces, an external electric field parallel to the film and a lateral voltage difference applied to both edges of the film, exhibits a universal rotational flow. In this article, we revisit this phenomena by considering an idealized so-called liquid-film motor and provide a theoretical description of the underlying physical mechanism that is responsible for the rotation. Based on this theory, the external electric field induces a non-uniform distribution of freely moving charges on the film. Then the internal field that is mainly resulted from the lateral voltage difference, will exert forces on induced charges and subsequently will result the rotational flow. We show, how the fields contribute in developing a universal flow pattern. [ABSTRACT FROM AUTHOR]

Recently, the fine dust produced by automobile non-exhaust systems has drastically increased. Brakes are a major source of fine dust, along with tires. Therefore, this study investigated the pressure drop characteristics of a filter for collecting fine brake dust using only disk rotational flow without a fan or pump. In addition, the effect of the gap between the filter and the disc on the particle behavior and the pressure change inside the filter housing was investigated. Finally, the change in collection efficiency according to filter pressure drop characteristics was examined in a particle collection experiment. As a result, it was found that the build-up in pressure inside the filter housing from the disk rotational flow was insufficient. This meant the brake filter requires a pressure drop as low as possible, as in Filter 1. The pressure drop performance of these filters had a profound effect on the leakage of particles through the housing gap, and the rate of particle concentration reduction inside the housing. Lastly, it was found that to increase particle collection efficiency, it is important to control the particles that rotate in close contact with the disc, which escape through the rear end gap. [ABSTRACT FROM AUTHOR]

An automatic feeder for fish feeding was manufactured and evaluated successively. Feed pellet size, air flow rate and feeder screw speed were the most important factors affecting the performance and efficiency of the automatic feeder. It was tested at 3 sizes of pellets (1, 2 and 3 mm), 3 air flow rates (10, 15 and 20 m3 min−1) and 5 screw speeds (180, 360, 540, 720 and 900 rpm). The automatic feeder productivity, efficiency, specific energy consumption and costs were determined. The obtained results indicated that the automatic feeder productivity increases with increasing feed pellets size, air flow rate and rotational speed of screw treatments under study, the automatic feeder efficiency increased with increasing rotational speed of screw until it reached the highest value at 540 rpm and then remain constant at 720–900 rpm and after that decreased with increasing speed. Meanwhile, the specific energy consumption of automatic feeder decreased with increasing feed pellets size, air flow rate and rotational speed of screw treatments under study. The total cost of using automatic feeder ranged from 0.09 to 0.16 EGP kg−1 ($ = 15.63 EGP) for all treatments under study. This feeder will save time, effort and cost for fish industry. [ABSTRACT FROM AUTHOR]

In the current study, a three-dimensional semi-coupling macrosegregation model was established for a curved bloom continuous casting strand. The fluid flow, heat transfer, and solidification were calculated firstly with the effect of the mold electromagnetic stirring (M-EMS) and final electromagnetic stirring (F-EMS). Then, the transport of the solute was solved after the fluid flow reached a steady state. Predicted values of the magnetic induction intensity, temperature, and content of carbon agreed well with the measured ones, respectively. The negative segregation in the subsurface of the bloom was generated due to the rotational flow induced by M-EMS. The rotational flow pattern was formed along the cross section of the F-EMS zone. The maximum tangential velocity 0.012 m/s was located near the solidification front. The distribution of the carbon was uniform and the concentration of the carbon was about 0.205 pct in the molten steel. From the position 11.1 to 20.1 m beneath the meniscus, the liquid fraction at the centerline of the bloom decreased gradually to 50 pct and the concentration of carbon increased from 0.2 to 0.24 pct. The concentration of the carbon at the centerline of bloom increased sharply to 0.29 pct at the solidification end. [ABSTRACT FROM AUTHOR]

Seasonal prediction of South China April to May rainfall is examined based on forecasts by the European Centre for Medium-Range Weather Forecasts (ECMWF) operational model. El-Niño Southern Oscillation (ENSO) is a major source of predictability, conveyed by the lower tropospheric anomalous western Pacific anticyclone and cyclone for El-Niño and La-Niña respectively. By separating ENSO into its diversity of eastern Pacific (EP) and central Pacific (CP) ENSO, different effects on South China rainfall are revealed. From observations, while rainfall is enhanced following EP El-Niño and reduced following EP La-Niña, rainfall remains close to climatology following CP ENSO. However, the seasonal forecast model predicts CP ENSO effect on South China rainfall to be similar to EP ENSO. The model develops excessive westward extension of the eastern Pacific cold tongue within seasonal timescale. While model predicts tropical central Pacific anomalous sea surface temperature (SST) following CP ENSO realistically, the colder mean state is proposed to weaken the anomalous convection, which subsequently induces bias in the western Pacific anomalous rotational flow and hinders South China rainfall prediction. Meanwhile following EP ENSO, the colder mean state is proposed to strengthen the thermocline feedback, inducing stronger tropical eastern Pacific anomalous SST. While bias in the western Pacific anomalous rotational flow is also induced, the bias is far away from South China so rainfall prediction is still realistic. This study highlights the importance of model mean state in the fidelity of model ENSO diversity teleconnections on seasonal timescale. [ABSTRACT FROM AUTHOR]

In the present study, a two-dimensional phase field model coupled with Lattice Boltzmann method (PF-LBM) is proposed to predict the dendritic growth and motion in the melt of Fe-C binary alloy, where the phase field method (PF) is used to calculate the dendritic growth, including the phase field and the concentration field, and the lattice Boltzmann method (LBM) is used to calculate the flow field. The dendrite motion is determined by Newton's Second Law and tracked by Lagrangian point in a Cartesian coordinate system. Later, the model validations were performed with the benchmark of a solid particle settlement in a stagnant fluid and particle motion in a shear flow, and the results show that the present model is capable of predicting the solid particle motion in the fluid flow. Finally, the model is adopted to investigate the dendritic growth and motion in a forced fluid flow (laminar flow or rotational flow), and the dendrite settlement in a terrestrial environment. The results show that when the forced fluid flow is a laminar flow, the free dendrite would be driven to translate, and the relative velocity between the dendrite and flow fluid decreases, resulting in weak influence of fluid flow on the dendritic growth. When the forced fluid flow is a rotational fluid flow, the dendrite would centrifugally rotate on the domain center with a counterclockwise self-spinning, and the rotation radius becomes larger and larger. For the case of dendrite settlement in a terrestrial environment, the relative movement between the dendrite and melt promotes the downward branch growth, but inhibits the upward branch growth, and two vortices form at the wake region of dendrite. Therefore, the settling dendrite shows a significant asymmetrical morphology. [ABSTRACT FROM AUTHOR]

Radial inflow turbine and nozzle among the other components of the cryogenic turboexpander has a significant effect on the efficiency of the system. This study proposes an effective one-dimensional design approach of a radial turbine by introducing different loss correlations. The methodology also describes the effect of non-dimensional design variables on the performance of the turbine. These variables (blade speed ratio, pressure ratio, hub and shroud to turbine inlet radius ratio) undergo artificial intelligence-based model to predict their optimal range for better efficiency and power output of the turbine. Based on these optimal ranges, two turbine and nozzle models are generated. The results of the optimized configuration show that the turbine total-to-static efficiency and power output are higher by 4% and 18.9% respectively as compared to the existing literature. Thereafter, the three-dimensional computational fluid dynamics (CFD) analysis is carried out to visualize the fluid flow and thermal characteristics at different inlet temperatures in the flow passage using ANSYS CFX®. The study also focuses to identify the flow separation zone, tip leakage flow, vortex formation, secondary losses and its reasons at different spans of the turbine. An experimental platform is also established to validate the CFD results of a case study. The experimental results show that the mass flow rate and rotational speed has major effect on temperature drop and isentropic efficiency of the turboexpander. The study highlights the importance of the design methodology, the estimation capability of artificial intelligence models, the experimental techniques and benchmarking model for numerical analysis at different cryogenic temperature. [ABSTRACT FROM AUTHOR]

The present discussion is about the unsteady two-dimensional flow of mixed convection and nonlinear thermal radiation in the presence of water-based carbon nanotubes over the vertically convected stretched sheet embedded in a Darcy' Forchheimer porous media. Saffman's proposed model is used for the suspension of fine dust particles in the nanofluid. A strong magnetic field (MHD) is applied normal to the flow which governs the Hall current effects. Khanafer Vafai Lightstone model estimated the effect of thermal conductivity and viscosity of the carbon nanotubes. Boundary layer approximation is utilized to built the nonlinear partial differential equations (PDEs). Similarity transformation is applied to convert these PDEs into the system of ordinary differential equations. Problem is solved numerically by bvp4c, using MATLAB software. It is observed through the analysis that the thermal field of nanofluid and the temperature boundary layer are much more higher than that of the dust phase, and these are further enhanced for the higher radiation parameter. [ABSTRACT FROM AUTHOR]

The analytical solution is derived for rotational frictional flow in a shallow layer of fluid in which the top and bottom Ekman layers join without leaving a frictionless interior. This vertical structure has significant implications for the horizontal flow. In particular, for a layer of water subjected to both a surface wind stress and bottom friction, the vorticity of the horizontal flow is a function not only of the curl of the wind stress (the classical result for deep water known as Ekman pumping) but also of its divergence. The importance of this divergence term peaks for a water depth around 3 times the Ekman layer thickness. This means that a curl-free but non-uniform wind stress on a shallow sea or lake can, through the dual action of rotation and friction, generate vorticity in the wind-driven currents. We also find that the reduction of three-dimensional dynamics to a two-dimensional model is more subtle than one could have anticipated and needs to be approached with utmost care. Taking the bottom stress as dependent solely on the depth-averaged flow, even with some veering, is not appropriate. The bottom stress ought to include a component proportional to the surface stress, which is negligible for large depths but increases with decreasing water depth. [ABSTRACT FROM AUTHOR]

The capabilities of controlling turbulence in a spherical Couette flow have been experimentally investigated. It is shown that, with increasing modulation amplitude of the outer sphere rotation velocity, the turbulence may be suppressed with a transition to laminar flow. The reverse process—the recovery of turbulence—is possible under decreasing amplitude. The destruction and reconstruction of turbulence are established to be accompanied by hysteresis. It is shown that, for small modulation amplitudes, suppression of turbulence is possible only within a narrow frequency band. [ABSTRACT FROM AUTHOR]

The swirling motion of blood flow is a widespread physiological flow phenomenon in the human body. The probability of cardiovascular and cerebrovascular diseases could be effectively reduced by swirling blood flow. In this study, first we proposed a new integrated vascular model with spiral folds on the inner wall. Based on the model, fluid-solid coupling simulation analyses of blood and blood vessels were performed. The results indicate that the spiral folds cause the swirling flow. This model provides new insights that may be of use for developing methods to generate swirling flow. Second, we discussed the specific effects of different fold parameters' characteristics on swirling flow. We found that increasing the pitch or cross-sectional area enhanced the swirling flow, specifically increasing cross-sectional diameter by 0.2 mm, wall shear stress by about 2 mm Hg, and deformation by about 0.2 µm. Finally, we proposed a new method to prepare an integrated artificial blood vessel based on the heteromorphic channel co-extrusion method; the inner wall of this blood vessel had a spiral fold structure and was micron scale in width. This study offers important guidance for the design of interventional treatments involving swirling flow. [ABSTRACT FROM AUTHOR]

Abrasive flow finishing (AFF) is one of the advanced finishing processes and rotational AFF (R-AFF) is one of its variant wherein workpiece is provided with additional rotational motion. Polymer rheological abrasive medium used in R-AFF process perform an important role in reducing the workpiece surface roughness. In the present paper, different types of in-house medium are prepared by varying composition of the silicon-based polymer, rheological additives, and abrasive particles. Later rheological characterization (static and dynamic) medium is carried out to understand the flow and deformation properties. Fourier transform infrared spectroscopic analysis of the medium is performed to find the new functional groups in the medium. To study the effect of various medium constituents on its rheological properties and finishing abilities, experiments are designed as per central composite rotatable design and analyzed using response surface methodology. The rheological study shows that, as the wt.% of silicon polymer and abrasive particles increases, maximum shear stress as well as complex viscosity also increases. Increase in wt.% of plasticizer and abrasive particles increases medium % viscous component. Viscous properties are dominant in soft silicone based medium and ΔRa increases with an increase in wt.% of silicone polymer. ANOVA analysis shows that wt.% of abrasive particles has highest effect on ΔRa and followed by wt.% of plasticizer. Better surface finish is achieved when 43.75% of silicone polymer, 36% SiC, 5% plasticizer, and remaining rheological additives-based medium are used. Among three workpiece materials, the best surface roughness is achieved on Al alloy/SiC (10%) metal matrix composite. [ABSTRACT FROM AUTHOR]

A model for the formation of rotationally nonequilibrated ensembles of gaseous molecular complexes is developed taking into account the vector dynamics of translational-rotational exchange and its manifestation as anisotropic light absorption and emission. The proposed model is used to calculate the optical anisotropy of an ensemble of molecular complexes as a function of the change of partial angular momenta and the ratio of moments of inertia of the starting fragments and the resulting complexes. The increase of additional angular momentum due to moments induced during rotational-translational exchange is shown to be capable of causing both a decrease and increase of anisotropy depending on the shape of the complex inertia ellipsoids. [ABSTRACT FROM AUTHOR]

We define general rotational surfaces of elliptic and hyperbolic type in the pseudo-Euclidean 4-space with neutral metric which are analogous to the general rotational surfaces of C. Moore in the Euclidean 4-space. We study Lorentz general rotational surfaces with plane meridian curves and give the complete classification of minimal general rotational surfaces of elliptic and hyperbolic type, general rotational surfaces with parallel normalized mean curvature vector field, flat general rotational surfaces, and general rotational surfaces with flat normal connection. [ABSTRACT FROM AUTHOR]

The drawback of steel fluid flow phenomena for a continuous casting mold under an electromagnetic stirrer with a traveling magnetic field is the resulting severe meniscus fluctuations due to the high-velocity and excessive downward flow in the casting direction. This can result in slab surface defects due to mold flux or inclusion entrainment. To inhibit these defects in the as-cast steel products, the implementation of braking forces using static magnetic fields in combination with a traveling magnetic field was studied in the current study. The numerical results of the fluid flow in the mold under a combined traveling and static magnetic field operation show not only 50 pct lower downward flow speed, but also more enhanced rotational flow to improve washing effects. The numerical results were validated in commercial-scale operations. The results suggest the optimized range of the ratio between the traveling and static magnetic flux densities is 65 to 75 pct to ensure steel quality improvements; this range maintains a balance between the fluid forces from the jet flow and the magnetic forces in the mold. [ABSTRACT FROM AUTHOR]

Having knowledge of fluid flows within the mold region of a billet continuous caster is of paramount importance to reduce a product’s internal and external defects. In this regard, a three-dimensional numerical model was developed to simulate the influence of the orientation of a five-port submerged entry nozzle (SEN) on the flow field of liquid steel within the mold region of a curved, square billet, continuous caster. The realizable k-ϵ turbulence model, together with the volume of fluid multiphase model, was used to simulate the effects of turbulence on these fluid flows, and their impact on the liquefied mold powder layer sitting on top of the liquid steel within the mold. The behavior of flows generated in the mold cavity was validated against previous experimental work. The numerical results showed that the modified SEN’s horizontal angle of rotation can significantly change the flow pattern within the billet mold. These changes can stabilize the liquid steel meniscus, which is expected to improve the quality of continuously cast products by decreasing mold powder entrainment. [ABSTRACT FROM AUTHOR]

We consider the problem of a rigid elliptical inclusion bonded to an infinite Kirchhoff isotropic laminated plate through a coating layer with two confocal elliptical interfaces. The rigid inclusion is subjected to a rotational moment, while the infinite (plate) matrix surrounding the coated inclusion is subjected to uniform remote membrane stress moments and bending moments. We find that the interfacial and hoop stress resultants are uniformly distributed along the inclusion-coating interface provided a set of four conditions on the rotational moment and remote loading are satisfied for specified material and geometric parameters characterizing the three-phase composite plate. [ABSTRACT FROM AUTHOR]