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This paper presents an investigation of the boiling heat transfer of R141b in a mini-channel with a 2.42-mm inner diameter filled with metal foam. Investigations are performed at velocity of 0.01 m s−1 and temperature of 450 K. The coupled level set and volume-of-fluid method is applied to simulate flow boiling in metal foam. It considers that the bubble number and the average bubble area have influence on the heat transfer coefficient. The simulation model is verified by experimental data with an emphasis on the effect of boiling bubbles and turbulent kinetic energy on heat transfer. The simulation results show that even though the bubble motion range and vortices area is smaller, more vortices appear in the channel filled with foam metal, which increase the mixing frequency and improve the heat transfer performance. Meanwhile, the heat transfer coefficient is inversely proportional to the average bubble area but proportional to the bubble number. The relationship between turbulent kinetic energy and heat transfer coefficient is also compared. Results indicate that the differentiation of turbulent kinetic energy to time appears consistent with the heat transfer coefficient in the mini-channel filled with metal foam. [ABSTRACT FROM AUTHOR]

The grid adjustment is seriously affected by the instability of Pumped Hydro Energy Storage plants (PHES), one of which is the phenomenon of Positive Slope (PS) in pump turbine. In this paper, two positive slopes were experimentally captured on one curve of the discharge-head performance in a pump turbine while only one positive slope is observed on one pump performance curve in general pumps. The similarities and differences of two positive slopes are demonstrated using data obtained with this pump turbine model. It is found that two positive slopes are caused by two different stalls, respectively. For the first positive slope, the stall with five stall cells in the vane-less domain (between impeller and wicket gates) is induced to play a key role. On each pump performance curve, with the smaller opening of guide vanes, the discharge of the first PS is less, until the first PS and the second PS becomes one PS. For the second positive slope, significant complex vortexes in the impeller inlet, the variations of cavitations and a lower signal of pressure fluctuation are observed. The discharges of the second positive slopes almost keep stable with the different wicket gates' openings. For their common characteristics, hysteresis phenomena are observed in both PS and are influenced by cavitations. • Two different positive slopes are captured experimentally in several pump turbines. • The hysteresis phenomenon is found in both positive slopes. • The mechanisms of two positive slopes are different. • Both positive slopes are influenced by the cavitation. [ABSTRACT FROM AUTHOR]

In order to investigate the turbulence-induced acoustic characteristics of hydrofoils, the flow and sound field for a model NH-15-18-1 asymmetric hydrofoil were calculated based on the mixed method of large eddy simulation (LES) with Lighthill analogy theory. Unsteady fluid turbulent stress source around the hydrofoil were selected as the inducements of quadrupole sound. The average velocity along the mainstream direction was calculated for different Reynolds numbers (R e). Compared to experimental measurements, good agreement was seen over a range of R e. The results showed that the larger the R e , the larger the vortex intensity, the shorter the vortex initial shedding position to the leading edge of the hydrofoil, and the higher the vortex shedding frequency (f s). The maximum sound pressure level (SPL) of the hydrofoil was located at the trailing edge and wake of the hydrofoil, which coincided with the velocity curl (ω) distribution of the flow field. The maximum SPL of the sound field was consistent with the location of the vortex shedding. There were quadratic positive correlations between the total sound pressure level (TSPL) and the maximum value of the vortex intensity (Γ max) and velocity curl, which verified that shedding and diffusion of vortices are the fundamental cause of the generation of the quadrupole source noise. [ABSTRACT FROM AUTHOR]

Summary: It is generally assumed that population supplementation will improve the genetic diversity of the recipient populations. However, the genetic outcomes of supplementations are rarely tested. We used population modelling to predict how the supplementation programme in a translocated Woylie (Bettongia penicillata ogilbyi) population influences their genetic makeup. Our model projections were then compared against real genetic data collected before and after supplementation, to determine whether or not supplementation was effective at increasing genetic diversity and to test the accuracy of the model. Post‐supplementation genetic diversity parameters (heterozygosity and allelic richness) were significantly higher following supplementation, and there was no significant difference from those predicted by the model. These results are encouraging; however, many factors can influence supplementation outcomes and we recommend ongoing monitoring in translocated populations to ensure that population trends are on target. [ABSTRACT FROM AUTHOR]

Tip leakage vortex (TLV) can seriously deteriorate the flow pattern and energy performance of hydraulic machinery, which is the key component in tidal energy system. A novel method of T shape tip is proposed to improve energy performance and suppress TLV for a NACA0009 hydrofoil. The T shape tip is formed by increasing foil thickness near tip, and the effect of thickening type and control curve pattern are further evaluated by numerical simulation validated by experimental results. The T shape tip remarkably suppresses the flow separation around the pressure side tip corner and decreases the pressure gradient in the clearance, further weakening the entrainment effect of the PTLV. Three thickening types are developed. The results show that the maximum increase of energy performance is 1.76% by the half suction side T shape, and the maximum decrease of vorticity is 18.75% by the T shape, while the half pressure side T shape shows slight effect. Moreover, three curve patterns including the straight curve, arc curve and parabolic curve are evaluated. The maximum increase of energy performance is 1.41% by the arc curve T shape, and the maximum decrease of vorticity is 21.53% by the parabolic curve T shape. • A novel method of T shape tip on energy improvement and vortex suppression is proposed. • Three thickening types and control curve patterns of T shape tips are developed and evaluated. • The maximum energy improvement by T shape tip is 1.76%. • The maximum suppression of vorticity by T shape tip is 21.53%. [ABSTRACT FROM AUTHOR]

This is the transcript of a public conversation held by a medium with Peirce's spiritual consciousness following an excellent dinner in the Delmonico Room at the Hôtel Fauchères in the evening of April 19, 2019, the 105th anniversary of Peirce's death. The transcript testifies to the continued reality of metaphysics in the afterlife, where one encounters the ultimate community of inquiry. It provides a number of revelations soundly supported by intricate semiotic distinctions. It also sets the methodological ground for a new subdiscipline of metaphysics open to a wide range of creative applications. [ABSTRACT FROM AUTHOR]

Tidal energy was one of the renewable and sustainable energy forms under rapid development in the past decades. In tidal energy conversion, the hydraulic machinery is the key work component. However, the tip leakage vortex and cavitation have negative influence on the energy performance and operation stability of hydraulic machinery. In the present work, a C groove method is developed to improve the energy performance and suppress the tip leakage vortex and cavitation around a NACA0009 hydrofoil in tidal energy conversion. The optimization mechanism of the C groove on the energy improvement and vortex suppression is that the groove can suppress the primary tip leakage vortex (PTLV) by the groove jet impingement, and suppress the secondary tip leakage vortex (STLV) by the groove channel flow. The numerical simulations under non-cavitation and cavitation conditions are conducted to investigate the effect of C groove with different groove depths. The results demonstrate that the C groove can improve the lift coefficient by a maximum rise of 1.04% under 50% δ , and improve the lift-drag ratio by a maximum rise of 2.85% under 25% δ , respectively. The C groove most effectively reduces the TLV volume and swirling strength under 50% δ. Meanwhile, the C groove makes the vortex core shrink and far away from the foil surface, and most effectively suppresses the TLV cavitation under 50% δ. Therefore, the groove depth of 50% δ is recommended as the optimal depth on suppressing the TLV cavitation. • C groove is developed to suppress vortex and cavitation. • C groove effectively suppresses TLV cavitation and improves energy performance. • Influence of C groove depth from 25% δ (tip clearance size) to 100% δ is investigated. • 25% δ improves energy performance by a maximum of 2.85%. • 50% δ presents a comprehensive optimal effect on suppressing TLV and cavitation. [ABSTRACT FROM AUTHOR]

Superconducting magnetic hysteresis properties of the ABO3-type Perovskites are investigated by the effective field theory. It is found that the core (B) atom of the ABO3 exhibits type II superconducting hysteresis behaviors when it interacts antiferromagnetically with the shell (A and O) atoms. Therefore, the magnetic hysteresis curve of B atoms in the ABO3 has binary coercive field points (lower coercivity; Hc1, and upper coercivity; Hc2). B atoms have a Meissner state at HHc2. Our results indicate that the superconducting properties of the ABO3-type Perovskites result from the antiferromagnetic interaction between the shell (O) and core (B) atoms. [ABSTRACT FROM AUTHOR]

In the framework of two-dimensional ideal hydrodynamics, we define a vortex system as a smooth vorticity function with a few local positive maximums and negative minimums separated by curves of zero vorticity. We discuss the invariants of such structures that follow from the vorticity conservation law and the invertibility of Lagrangian motion. Introducing new functional variables diagonalizing the original noncanonical Poisson bracket, we develop a Hamiltonian formalism for vortex systems. [ABSTRACT FROM AUTHOR]

The paper examines the mechanics and physics of granular material responses at the macroscopic and microscopic levels during both monotonic and cyclic loadings. A numerical analysis referring to a long retaining wall is conducted using a two-dimensional discrete element model representing a granular system with a free top surface. On one of the lateral boundaries referring to the retaining wall, both active and passive loadings were applied monotonically as well as cyclically. First, the development of sheared zones and classic failure wedges resulting from active and passive monotonic displacements are discussed with respect to Rankine's and Roscoe's solution angles. Then, a series of loading cycles were performed using slow small-amplitude displacements at different stress states chosen before the occurrence of failure along the passive monotonic stress response curve. Particular interest is focused on the ultimate asymptotic cyclic response of the granular system, the occurrence of a high-mobility (convective) zone and a detailed macroscopic and microscopic analysis. Finally, major kinematical features that are displayed during cyclic loading from different starting stresses to eventually reach the same asymptotic state were elucidated through particle vortex-like flux formations, including contact rotations. The change in material stiffness was also investigated based on the evolution of strong and weak contact networks, together with the analysis of fabric anisotropy within the entire domain, including the high-mobility zone considered separately. [ABSTRACT FROM AUTHOR]

The formation of field‐aligned currents (FACs) of a substorm current wedge is a key element of substorms. Conjunctive observations of a downward FAC during a substorm on 20 December 2007 were made in space by THEMIS satellites and on the ground by geomagnetic field and aurora stations, which provides a unique opportunity to investigate the generation of downward FAC. On the ground, AL index decreased significantly at 04:17:00 UT, denoting the onset of the substorm. The geomagnetic perturbations observed at the postmidnight station KUUJ show that the FAC of the substorm current wedge flowed into the ionosphere. Meanwhile, in space, two THEMIS satellites, THC and THB, the magnetic footprints of which were close to the postmidnight station KUUJ, were located in the near‐Earth magnetotail and recorded the outside‐in signatures of the plasma sheet thinning first and then the large‐scale inside‐out propagating plasma flow vortex inferred from the rotation of the flow vector. The magnitude of the FAC was estimated by using the bipolar BY perturbations associated with the flow vortex. It is found that this FAC was so strong that it cannot be produced by the time derivative of the vorticity and that the pressure gradient may act in this event. The upward flowing low‐energy electrons are the possible carriers for this FAC.Key Points: Conjunctive observations of the downward FAC of a SCW in space and on the ground are reportedThe observing satellites recorded the outside‐in and the inside‐out signatures sequentially during the substorm in the near‐Earth tailThe downward FAC is observed to be associated with a flow vortex inferred from the rotation of the flow vector [ABSTRACT FROM AUTHOR]

We investigate the propagation of the first-order chirped Airy vortex (FCAiV) beams in a quadratic index media analytically by applying the Huygen-Fresnel integral. The intensity, the phase, the energy flow density, and the angular momentum density are investigated for different chirped parameters, decay factors and parameters related to the gradient refractive index. There is an inversion of the self-acceleration of the FCAiV beams during the propagation. The FCAiV beams propagating in the quadratic index media hold a periodic evolution. The focusing intensity, the intensity distribution, the centre of mass of the FCAiV beams can be controlled by choosing different parameters. [ABSTRACT FROM AUTHOR]

This paper is mainly to study the mixing efficiency and pressure drop of the Minkowski fractal obstacle micromixers. The mixing efficiency of primary Minkowski fractal obstacle (PMFO) micromixer and secondary Minkowski fractal obstacle (SMFO) micromixer are compared at five kinds of Reynolds numbers. With the increase of obstacle height and the decrease of distance, the chaotic convection in the microchannel is enhanced. Especially at obstacle height (h) = 0.2 mm, obstacle distance (D) = 0.15 mm, and Re = 100, the vortex caused by the Minkowski fractal obstacle structure is more obvious. In addition, vortex phenomenon increases the contact area of two fluids and enhances chaotic convection. It shows that the flow direction of the fluid in the microchannel varies significantly. [ABSTRACT FROM AUTHOR]

By using the Stereo Particle Image Velocimetry (PIV) technique we observe the secondary flow of second kind in a corner of a channel of square cross-section. The boundary layer thickness is much lower than the channel size. Therefore, the flow is still developing, not filling the entire channel cross-section, which is the case more widely reported in literature studied in a very long channel. The non-linear secondary effects of interacting boundary layers are observed as a single stream-wise vortex close to the channel corner in case of laminar boundary layers. In the case of turbulent boundary layers, the secondary flow takes shape of a symmetric pair of counter-rotating vortices. This pattern is observable only in the average velocity field, while the instantaneous ones display large amount of vortices, whose spatial distribution close to the corner in dependence on their orientation leads to statistically emergent net vorticity. At the same time, this pattern is reproduced by using a numerical simulation. • Secondary flow of second kind in a short channel observed by Stereo PIV • For R e L ≤ 1. 0 ⋅ 1 0 5 , the secondary flow is laminar in shape of single vortex in the corner. • The size of laminar secondary flow vortex decreases with R e L as R ∼ R e L − 1 ∕ 2 . • At R e L ≥ 1. 3 ⋅ 1 0 5 , a pair of counter-rotating vortices appears in the averaged sense. • This pattern develops also in a "steady-state" numerical simulation. [ABSTRACT FROM AUTHOR]

To analyze the accuracy and differences of diverse turbulence models in predicting the flow around baffles of self-designed wet dust treatment system, several representative Reynolds Averaged Navier-Stokes (RANS) models of Standard κ-ε, RNG κ-ε, SST κ-ω and RSM were selected to simulate the vortex flow induced by arc baffles respectively, and the simulation result was also compared with experiment data. The simulation parameters mainly include the vortex structure, pressure distribution and velocity distribution, and the results show that all the simulations based on the four turbulence models can roughly describe the main characteristics of the vortex flow around baffles, while the Standard κ-ε and RNG κ-ε modes are more accurate. For the pressure drop and total pressure distribution, the results of Standard κ-ε model deviate from the other models, and the decreasing sequence of predicted values is Standard κ-ε，RNG κ-ε，RSM and SST κ-ω. The predicted results of RNG κ-ε model for longitudinal velocity are the closest to the experiment data, while the accuracy of SST κ-ω model for predicting near wall flow and lateral velocity is relatively high. [ABSTRACT FROM AUTHOR]

Jet in cross flow is an important issue in engineering practice, for example, it is used to improve turbine efficiency in film cooling. In this study, the large eddy simulation and the spectrum analysis are employed to analyze the vortices in a jet in cross flow. The results show that the Rortex method more accurately identifies the vortex structures than other methods. In the analysis of the evolution of the spatial vortex structures, it is affirmed that the spectrum analysis using the Rortex value can effectively identify the characteristic vortex structures in a jet in cross flow. [ABSTRACT FROM AUTHOR]

The structure of the wind concentrator will directly affect the performance of wind-concentrating turbine. In this paper, to optimize the structure, the CFD software was used. The structure was optimized by adding a new conical tube behind the diffuser of the original model, and the influence of both the generatrix length (d) and the deflection angle (β) of the conical tube on the concentrator was also analyzed. First, through the CAD software, the optimized model of a wind concentrator was built and a cylinder (diameter: 20 m; length: 30 m, coaxial with the model) was created. With the help of Boolean subtraction, the fluid field model was obtained by subtracting the optimized model from the cylinder. The patch conforming algorithm was used to mesh the fluid field and the mesh type was tetrahedral. Twenty inflation layers were divided in the thickness range of 1 cm marked on the optimization model. In the simulation, SST k-ω turbulence model was adopted, energy equation was used and heat exchange was considered. The air velocity, temperature, density, pressure, viscosity, thermal conductivity, constant pressure specific heat capacity, flow rate, turbulent kinetic energy k value and specific dissipation rate ω value were 10.83 m/s, 296.75 K, 1.044 kg/m³, 88 800 Pa, 1.85×10-5 kg/(m·s), 0.026 22 W/(m·K), 1 013 J/(kg·K), 3 552.048 kg/s, 0.165 382 m²/s², 11.786 s-1, respectively. The inlet boundary was the mass flow inlet, and the velocity direction was perpendicular to the inlet boundary. Both the thermal boundary conditions of the wall of the concentrator and the shell of the fluid field were at fixed temperature, with a value of 296.75 K. Pressure outlet was used as the outlet boundary. The results of flow field calculation show that the model was optimal when the generatrix length and the deflection angle of the conical tube were 0.4D and 50° respectively. The concentrating performance of the optimized model was determined by the vortex behind the conical tube and the flow separation on the inner surface of the tube. The existence of vortices rendered the optimized model better than the original one. However, if the intensity of the vortices was too high, the air ejected from the outer edge of the conical tube would be attracted to the inner wall of the tube and would affect the radial diffusion of the air up-flow at the outlet of the diffuser, thus reducing the originally superior concentrating performance. Meanwhile, the flow separation also reduced the concentration performance. Conversely, if a strong vortex appeared behind the conical tube, and the flow separation near the inner surface of the tube was not so strong, the optimal condition will be reached. At this time, the generatrix length was 0.4D and the deflection angle was 50°. Besides, when the deflection angle was 50° and the length of generatrix was extended, the vortex intensity behind the conical tube would increase, and the concentrating performance of the concentrator would improve. However, the flow separation was easy to occur near the inner wall of the conical tube, thus reducing the concentrating performance. But when the generatrix length was 0.3D, flow separation appeared. When the generatrix length was 0.4D, the flow separation was very slight. And when the generatrix length was extended to 0.5D, strong flow separation occurred, dampening the enhancement of the concentrating performance. Compared with 0.5D, When the generatrix length was 0.6D, the flow separation was slighter. So, for cost-effective consideration, when the deflection angle was 50°, 0.4D was the best generatrix length. [ABSTRACT FROM AUTHOR]

The deteriorating nature of severe functional tricuspid regurgitation (FTR) has led to the heightened interest in this pathology. However, therapies are heterogeneous and an ideal technique is uncertain. The hemodynamic impact on the cardiac chamber following therapeutic repairs has not been well studied, while its analysis could be used to predict the treatment success. In this study, the hemodynamics of the right ventricle (RV) after 1) clover edge-to-edge tricuspid repair, and 2) double orifice tricuspid repair was evaluated in three right heart models using an ex vivo pulsatile platform emulating severe FTR with the aid of stereoscopic particle image velocimetry. Although all repairs substantially reduced tricuspid regurgitant area, they resulted in a more than 50% reduction in diastolic tricuspid valve (TV) opening area. Splitting the TV orifice into multiple smaller orifices by both repairs eliminated the ring-shaped vortical structure inside the RV observed in FTR cases. Postrepair RV domain was mostly occupied with irregular vortical features and isolated vortex residuals. Moreover, vortical features varied among repair samples, indicating enhanced sensitivity of RV flow to postrepair TV morphology. Compared with clover repair, double orifice subjected the RV to enhanced swirling motions and exposed more regions to vortical motions, potentially indicating better rinsing and lower risk of mural thrombus formation. Double orifice repair increased the levels of RV mean kinetic energy and viscous energy loss than those observed in clover repair, although the impact of these on the cardiac efficiency remains unclear. These preliminary insights could be used to improve future treatment design and planning. NEW & NOTEWORTHY While clover and double orifice tricuspid repairs markedly improved leaflet coaptation, they substantially reduced diastolic tricuspid opening area. Postrepair right ventricle (RV) exhibited specific hemodynamic traits, including the loss of ring-shaped vortical structure and the enhanced sensitivity of RV flow to postrepair tricuspid valve morphology. Compared with clover technique, double orifice repair led to higher swirling motions in the RV domain, which could indicate lower risk of mural thrombus formation. [ABSTRACT FROM AUTHOR]

Drops loaded in calcium ions detach from stalactites and impact the underlying stalagmites, thereby allowing these latter to grow through calcite precipitation. Nevertheless, little is known about the influence of the drop free fall and splash dynamics on stalagmite shape and width. Through high-speed imaging of impacting drops on stalagmites from several caves, we observed that the impact point position of the drops is scattered, sometimes over several centimetres. We show that this dispersal has no external cause and must, therefore, be self-induced. Using a Langevin-like equation, we then propose a prediction of the impact point dispersal as a function of the falling height travelled by the drops. We finally show that measured stalagmite widths are correlated to the dispersal in the impact point position of the drop. [ABSTRACT FROM AUTHOR]

The testing of irradiated silicon detectors requires maintaining low (≤ -10 °C) temperatures, to simulate a realistic operating environment and prevent annealing effects from distorting the results of the measurement. Keeping a device cool and dry is challenging, particularly if the apparatus must be portable. This paper presents a solution for a providing a stable, cool and dry environment for testing an irradiated silicon detector, that is easy to transport and can be installed in charged particle beam areas and irradiation facilities. [ABSTRACT FROM AUTHOR]

In this work, large eddy simulation combined with volume of fluid method is performed to simulate the flow and the associated vortices in a pump sump. The numerical results are compared with experimental data. Particular interest is paid to discovering the temporal evolution of the free-surface and floor-attached vortices. Both vortices undergo periodic enhancement and attenuation due to the advection and stretching/tilting effects generated by the background flow. The primary vortex core is accompanied by spirally wrapped secondary vortex tubes, resulting in anisotropic turbulence structure around the vortex core regions. The findings provide a deep insight into the application of large eddy simulation in pump sump and the underlying mechanism of vortex formation and evolution in the sump. [ABSTRACT FROM AUTHOR]

Based on the unsteady viscous flow simulation, the flow characteristics inside the supersonic jet Element have been investigated numerically. The results have revealed that once the specific structures of the supersonic jet element are finalized, even if the boundary conditions remain unchanged, the corresponding internal flow will also shows strong unsteady in a certain range of primary gas source pressure. The instability of the main vortex center is a main reason to make the output thrust of the supersonic jet components fluctuate all the time in the attached wall condition. At the deflection of the jet stage, once the static pressure for the right side of the wedge exceeds the left side, the transverse expansion for the stripping zone near the right output channel entrance can play a significant role in making the primary jet deflect successfully. When the jet starts to attach the wall layer, due to the "Coanda" effect, the jet also can attach the layer successfully even though the corresponding control flow is totally closed. When the jet enters the adjustment stage, the thrust changes process for the left and right outputs will experience two typical stages: adjusting and adjusted stages. The corresponding vortex structures at different switching time together with the force variations etc. inside the jet Element have been obtained computationally and analyzed in details. • The instability of main vortex center is a main reason to make the output thrust fluctuate. • The transverse expansion for the stripping zone can make the primary jet deflect successfully. • Jet can attach the layer successfully due to "Coanda" effect even though control flow is totally closed. • The thrust changes process will experience two typical stages: adjusting and adjusted stages. [ABSTRACT FROM AUTHOR]

In this paper, for the first time, we developed the measurement method of the topological charge (TC) in millimeter wave with helical wavefront by a triangular aperture. The millimeter wave with helical wavefront was passively generated by conversion from a Gaussian beam using a spiral mirror, which we also developed. Each diffraction pattern depended on TC, and negative TC and positive TC were symmetric pairs under reflection. These diffraction patterns were perfectly compatible with the calculation results. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to assess the factors influencing the late diastolic vortex in normal and abnormal ventricles. Methods: Color Doppler data in left ventricle (LV) were acquired from apical long‐axis view and analyzed using vector flow mapping in 57 patients with coronary artery disease, 57 patients with dilated cardiomyopathy, and 53 healthy volunteers. Results: In normals, corrected area and flux of the end‐diastolic vortex were positively correlated with transmitral A velocity and heart rate. Subjects with E/A <1 had higher vortex flux than those with E/A >1. Heart rate was the only independent predictor of corrected vortex area (R2 = .170, P = .004), and transmitral A velocity and heart rate were the independent predictors of corrected vortex flux (R2 = .490, P < .001). Patients with various mitral filling patterns showed significant differences in vortex area and flux. The vortex area and flux were positively correlated with transmitral i velocity and a′. Transmitral A velocity was the only independent predictor of corrected vortex area (R2 = .180, P < .001), while transmitral A velocity, heart rate, LV end‐systolic short diameter, and end‐diastolic long diameter were the independent determinants of corrected vortex flux (R2 = .593, P < .001). Conclusions: The end‐diastolic vortex is formed and mainly affected by the late LV filling. The compensatory atrial contraction may enhance the end‐diastolic vortex that facilitates coupling between diastole and systole. LV size can influence the end‐diastolic vortex in patients with LV dysfunction and enlargement. [ABSTRACT FROM AUTHOR]

Zusammenfassung Majorana‐Fermionen sind zugleich ihr eigenes Antiteilchen, folglich dürfen sie keine elektrische Ladung besitzen. Ob es sie in der Natur gibt, ist offen. Theoretisch sind sie aber als Quasiteilchen in Festkörpern erzeugbar. Topologische Supraleiter könnten ein dafür geeignetes System sein. Experimentell sind sie durch eine Art Feldeffekt‐Transistor‐Anordnung herstellbar. Dessen Kanal besteht aus einem Halbleiter‐Nanodraht, der teilweise mit einem Supraleiter beschichtet sein muss. An der Grenzfläche entsteht ein topologischer Supraleiter, in dem Majorana‐Zustände theoretisch realisierbar sind. Experimentell gibt es inzwischen starke Indizien dafür, doch eindeutig nachgewiesen ist ihre Existenz noch nicht. Diese Majorana‐Zustände sind nicht allein für die Grundlagenforschung interessant. Sie versprechen auch räumlich verteilte und damit gegen lokale Störungen besonders stabile Quantenbits für Quantencomputer. Deshalb ist die Quanten‐Informationstechnologie stark an den Majorana‐Zuständen interessiert. [ABSTRACT FROM AUTHOR]

Barotropic geostrophic flows are investigated using rectangular and polar coordinate systems. It is shown that, for the analysis of geostrophic flows with radial symmetry, the use of a polar coordinate system is preferable. Relations between the hydrodynamic characteristics, including the expressions of the fluid particle velocity components and vorticity through pressure, are obtained. It is established that, in the case of stationary barotropic flows, isobaths coincide with current lines. Stationary radially symmetric geostrophic flows are considered. [ABSTRACT FROM AUTHOR]

Abstract The ultra-small axial flow hydraulic turbine is a portable, palm-sized hydraulic turbine that can be applied to low head applications. By redesigning the original runner of this turbine using a method which uniformized the axial flow velocity, we succeeded in improving the performance of the runner. However, the mechanism of the improved performance of the optimized runner was not sufficiently clear; furthermore, the internal flow of the ultra-small axial hydraulic turbine had hardly been elucidated. This study aims to elucidate the internal flow structure of the ultra-small axial flow hydraulic turbine and to clarify the mechanism behind the improved performance of the optimized runner. To this end, we investigated in detail the internal flow structure of the original and optimized runners using PIV measurements and numerical analysis, focusing on the vortex structures. As a result, it was found that losses due to the tip leakage vortex and vortices near the hub at the blade outlet were smaller for the optimized runner than for the original runner. In particular, it was found that the turbine efficiency was greatly improved because vortices due to the swirling flow downstream of the runner were suppressed, and losses resulting from these vortices were thus reduced. Highlights • Ultra-small axial flow hydraulic turbine is palm-sized. • The internal flow structure of the turbine was revealed. • Vortexes that cause losses were identified. • The mechanism behind the improved performance of the optimized runner was clarified. [ABSTRACT FROM AUTHOR]

Dye liquid visualization and PIV experiments were conducted to reveal the influence of the Reynolds number (Re) and the presence of an end plate at the upper boundary on the annular flow dynamics characteristics of coaxial cones. The key flow information, such as the vorticity and velocity distributions, time-averaged flow field, and Reynolds stresses, were obtained by processing the velocity field. The Taylor vortex dynamics mechanism was studied based on the quantitative evaluation of the periodic vortex transformations. The experimental results showed that there was upward flow in the annulus at very low Reynolds numbers (Re = 107 and 160), and the annular flow transitioned from an upward to a downward pattern as Re (Re ≥ 214) increased. The first vortex was always separated by a negative vortex, B2, generated in the top right corner for Re = 214–642. A counterclockwise vortex under the free water surface always formed because the centrifugal force dominated at the water level, and there was always a fixed clockwise vortex under the upper cap because the dynamic pressure dominated at the non-slip wall surface for Re = 214–1925. The dominant convex outward or concave inward flow reflected the dominant motive source force. The total Reynolds stress increased with the increase in Re, and the magnitudes of the stresses were in the following order: radial normal stress > axial normal stress > shear stress. [ABSTRACT FROM AUTHOR]

We investigate spatiotemporal vortex rings with phase dislocation both in space and time. It is demonstrated that these structures naturally appear as a periodical in time edge phase dislocation at the low-density region of a perturbed atomic Bose–Einstein condensate. The condition of formation, dynamics and stability of the spatiotemporal vortex rings are investigated for repulsive and attractive interatomic interactions. These theoretical findings open up a perspective for experimental observation of novel type of topological coherent structures in ultracold gases. [ABSTRACT FROM AUTHOR]

Connecting storm-sewers located at rather different elevations may be made with vortex drop shafts in which the energy dissipation is made by the friction between the vertical shaft and the flow and downstream by the impinging jet in a dissipation chamber. Following the first model design in the 1940s, different types of vortex drop shafts have been developed. One of the most used type is the so-called spiral vortex drop shaft developed to work in supercritical flow with good performance in both energy dissipation and space constrains. In this paper, an experimental flow characterization in a spiral vortex drop shaft is conducted covering the three main components of these structures, namely the inlet channel, the vertical shaft and the dissipation chamber. The results include measurement of water depths, pressure and velocity. [ABSTRACT FROM AUTHOR]

A micro-electromechanical plate resonator suspended 2 μ m above a substrate was immersed in 4 He at 14 mK at saturated vapor pressure. At these temperatures, four vibrational modes of the device are observed. The corresponding motion of these modes is identified by comparing the observed modes with computer simulations. Owing to its large surface area and small mass, the resonator is sensitive to remnant vortices. The behavior of the modes is studied in the presence of remnant vortices and also in the presence of fully developed turbulence generated by a quartz tuning fork. [ABSTRACT FROM AUTHOR]

This study was aimed to develop a self‐nanoemulsifying drug delivery system (SNEDDS) for amphotericin B (AmB) potential use in leishmaniasis through topical and oral routes. Two formulations, formulation A and formulation B (FA and FB) of AmB loaded SNEDDS were developed by mixing their excipients through vortex and sonication. The SNEDDS formulation FA and FB displayed a mean droplet size of 27.70 ± 0.5 and 30.17 ± 0.7 nm and zeta potential −11.4 ± 3.25 and −13.6 ± 2.75 mV, respectively. The mucus permeation study showed that formulation FA and FB diffused 1.45 and 1.37%, respectively in up to 8 mm of mucus. The cell permeation across Caco‐2 cells monolayer was 10 and 11%, respectively. Viability of Caco‐2 cells was 89% for FA and 86.9% for FB. The anti‐leishmanial activities of FA in terms of IC50 were 0.017 µg/ml against promastigotes and 0.025 µg/ml against amastigotes, while IC50 values of FB were 0.031 and 0.056 µg/ml, respectively. FA and FB killed macrophage harboured Leishmania parasites in a dose‐dependent manner and a concentration of 0.1 µg/ml killed 100% of the parasites. These formulations have the potential to provide a promising tool for AmB use through oral and topical routes in leishmaniasis therapy. [ABSTRACT FROM AUTHOR]

Electrostatic precipitators (ESPs) separate particles from flue gas by corona discharge and accompany by the generation of ionic wind. In this work, a Computational Fluid Dynamics model was presented to investigate the effects of ionic wind on flow field and particle precipitation in a honeycomb ESP in terms of the coupled processes among corona discharge, gas flow, particle charging and transport. Results indicated that the electric field and ion charge density around the needle tips were highest and respectively reach 2.5 × 106 V/m and 0.164 C/m3 in the gas without suspended particles, which played a key role in corona-electrostatic field. The maximum velocity of ionic wind could reach 13.81, 11.74 and 9.42 m/s under the applied voltage of 27, 21 and 15 kV, and ionic wind velocity sharply decreased away from the needle tip. Meanwhile, the flow field could be divided into three regions (ionic wind affected region, vortex and back flow region) according to the direction of gas flow velocity. When the electrically neutral particles with a spherical shape were injected into ESP at the entrance, the charged particles were transported by drag force and electric force, and inhomogeneous distribution of the deposited particle has occurred because of ionic wind. More intense vortices were formed with the increase in applied voltage, and promoting the particle precipitation process. Moreover, higher applied voltage enhanced the aggregation of particles in the upstream, and reduced the dead zone of deposited particles in the downstream. The ionic wind generated by corona discharge strongly disturbed the flow field and particle precipitation process. Image 1 • A 3D spike-honeycomb ESP model was established to study the role of ionic wind. • The distributed pattern of the electric field and ion charge were investigated. • High velocity ionic wind was generated near the tips and could reach 13.81 m/s. • The flow field of gas phase was divided into three regions because of ionic wind. • The correlation between the ionic wind and particle precipitation were analyzed. [ABSTRACT FROM AUTHOR]

Background: A vortex is a rotational fluid structure formed by shearing of fluid layers. It forms during diastole in the left ventricle (LV) and helps redirect flow to the LV outflow tract for ejection, optimizing energy conservation. The aim of this study was to demonstrate the feasibility of detecting and analyzing LV vortices using a new ultrasound technique known as blood speckle imaging (BSI). Methods: Conventional and BSI parameters were acquired in preterm infants referred for echocardiography. BSI feasibility and reliability were explored using highest frequency settings and optimized Nyquist limits. Vortex area was determined by tracing the outer vortex ring at maximum area. Peak vortex formation time (PVFT) was determined at time of maximum vortex area relative to the R‐wave, and vortex duration from frame‐by‐frame analysis of first appearance to vortex degradation. Results: Left ventricle vortices were detected in 49 of the 50 preterm infants (weight 500–2020 g) with excellent intra‐ and inter‐observer reliability. Mean vortex area indexed to LV area was 0.19 (0.08). Peak vortex formation time was at 87 (7)% of the cardiac cycle, and vortex duration lasted 13 (4)% of the cardiac cycle. Vortex area correlated positively with LV length, end‐diastolic dimension, end‐diastolic volume, mitral annular (R +0.42, +0.50, +0.47, +0.50, all P < 0.01), and transmitral Vti (R +0.37, P < 0.01). PVFT correlated negatively with E, EA, and Ee' (R −0.42, −0.47, −0.47, all P < 0.01). Conclusion: Left ventricle vortex formation can be analyzed with two‐dimensional BSI and has the potential to complement existing parameters of cardiac health. [ABSTRACT FROM AUTHOR]

• Rarefied gas flow in a microchannel with backward facing step is simulated by LBM. • Mach number, pressure, and mass flow rate are studied in slip and transient regimes. • Results obtained by LBM have a good agreement with the results of DSMC method. • Mach numbers in transient regime are lower than Mach numbers of slip one. • Slip regime has lower values of Knudsen number as compared with transient one. In this paper, the rarefied gas flow in a microchannel with backward facing step is simulated by Lattice Boltzmann method. A model with two relaxation times in slip and transient flow regimes is used. The slip velocity in the walls of the microchannel is improved by using the wall operation function, known as power-law analytical function. The advantage of this model in comparison with a single relaxation time model is the accuracy of the slip velocity and its advantage over a model with a multiple relaxation times is the low cost and running time along with simplicity of programing. The boundary conditions used in the inlet and outlet sections of this geometry are Zou-He condition and the bounce back and Specular Reflection boundary condition is considered on the walls. The profiles of Mach number, pressure, and mass flow rate are studied in the slip and transient flow regimes at Reynolds numbers of 6.43 and 0.052, respectively. The effects of Knudsen number on the velocity and vortex formation are also discussed. The results are also compared with the results obtained by the Direct Simulation Monte Carlo method and a good agreement between two results is observed, which shows the accuracy of the model. [ABSTRACT FROM AUTHOR]

This paper presents a numerical simulation investigation of the hydrodynamic and acoustic characteristics of ventilated supercavities that operate at various ventilation rates. The large eddy simulation (LES) and Ffowcs Williams–Hawkings (FW-H) methods are used to solve the unsteady flow field and noise. The results show that the ventilation rate plays an important role in cavity closure forms and can improve hydrodynamic performance. There is a transition from re-entrant flow closure to a stable double-vortex tube closure form at the supercavity tail as the ventilation rate increases. Meanwhile, under the condition of a high ventilation rate, the re-entrant flow region in the cavity gradually shrinks and hairpin vortices appear, the body length of the cavity increases,and the unsteadiness at the supercavity tail is weakened. However, the turbulence intensity and integral scale both increase with the ventilation rate. Moreover, it is found that the noise is closely related to supercavity closure form. Ventilated supercavities with closure forms of double-vortex tubes have better noise performance. Interestingly, as the ventilation rate increases, the total sound pressure levels are improved. The wavenumber-frequency spectra of supercavity turbulent pulsating pressures under studied ventilation rates are similar, but there are some differences in some local areas. • The effects of ventilation rates on the closure forms of cavity tail are investigated. • The evolution of vortex structure in ventilated cavitation flow is analyzed. • The supercavity noise, turbulence intensity and wavenumber-frequency spectrum are evaluated. [ABSTRACT FROM AUTHOR]

Magnetic nanodisks and nanorings have been focus of attention for quite some time due to their applicability in magnetic memory devices. In this paper, static and dynamic magnetic properties of Permalloy concentric thin ring nanostructures are reported as a function of the number of rings by using micromagnetic simulations. The maximum outer radius (R) and thickness (t) of the concentric rings are fixed at 100 nm and 20 nm respectively. The distance between any two neighbouring rings is always maintained equal to the width of each ring while the number of nanorings is increased starting from one to five. In-plane magnetic hysteresis loops show that in all cases, the remanence and coercivity values are found to be almost zero while vortex state is exhibited with opposite helicity in adjacent nanorings. When the number of nanorings reach five, the narrowest hysteresis loop is observed with almost no hysteresis at all. Dynamic susceptibility spectra was computed by relaxing the system from a out of plane saturated state followed by an in-plane excitation using a small field pulse. In most of the cases, the in plane magnetic field pulse excites azimuthal spin wave modes. The resonance frequency corresponding to these excitation modes depends on the remanent configuration and the number of peaks increase with increment in the number of rings. The ferromagnetic resonance mode that is common for all the samples considered, moves towards lower frequency with increase in number of concentric rings. • In plane hysteresis of concentric nanorings yield vortex states at remanence. • Frequency response of concentric nanoring system is explored. • In-plane field pulse excites azimuthal modes of order 1. • New modes prop up with increased number of nanorings. • Frequency of most intense mode decreases with more concentric rings. [ABSTRACT FROM AUTHOR]

Vacuum pump is widely used in aviation, chemical, semiconductor and other fields because of its superior performance. In order to study the internal flow characteristics and pump performance, 1-D Chamber Model method and the CFD modelling method based on static grid are commonly used, such methods ignore many important three-dimensional transient flow details. However, in numerical modelling of three-dimensional transient flow field for hook and claw-type vacuum pump with cusps in the rotor profile, the generation of flow field grid is always a challenge. The body-fitted mesh method is difficult to generate effective dynamic grid for such kind of fluid domain, which usually leads to the divergence of calculation. In order to solve these problems, the cut cell Cartesian method is proposed to simulate the three-dimensional transient flow field in hook and claw-type vacuum pump. Firstly, the mathematical basis of the cut cell Cartesian method was introduced in detail, in which the immersed boundary method (IBM) was combined with the generation process of adaptive Cartesian volume mesh. Aiming at modelling the hook and claw-type vacuum pump, firstly, the profile design method of hook and claw-type vacuum pump was derived, and the geometric model of the calculation domain was established. The transient flow field characteristics of the vacuum pump with different inter-lobe clearance sizes were analyzed, and the velocity, pressure, vortices and temperature characteristics inside the vacuum pump were obtained. The influence of clearance variation on the performance of the vacuum pump was discussed. The feasibility and accuracy of the method were verified by a study case of a two-stroke reciprocating piston pump. The research provides a good reference for dynamic grid generation and precise numerical simulation of hook and claw-type vacuum pump. • The cut cell cartesian method is used to grid generation of hook and claw-type vacuum pumps with cusps. • A gap model is used to simulate the flow field at the gap. • The feasibility and accuracy of the cut cell cartesian method are verified by the case of a piston pump. • The flow characteristics of vacuum pump with different inter-lobe clearance sizes are analyzed by 3-D numerical modelling. [ABSTRACT FROM AUTHOR]

• 1A transient model is used to simulate gas carrying liquid flow in different inclination pipeline. • The critical velocity of gas carrying liquid at 10°, 20° and 30° inclination angles are identified. • When gas velocity reaches the critical velocity, the vortex is the smallest and flow accelerated corrosion is the weakest. • The flow accelerated corrosion sensitive areas and the main reason of the flow accelerated corrosion are determined. Shale gas reserves are abundant and widely distributed. As a green and clean energy source, it has tremendous development potential. Nonetheless, the shale gas transmission process is often accompanied by liquids. The gas transmission will transform to liquid-carrying gas transmission and liquid will accumulate in low-lying areas. These will accelerate pipeline corrosion and perforation, threatening pipeline safety and causing significant economic losses. In this paper, computational fluid dynamics (CFD) can be used to establish a transient model of liquid-carrying gas flow. The flow characteristics of liquid-carrying gas in the up-dip shale gas gathering pipelines are studied. The critical flow velocities at 10°, 20°, 30° can be determined 8.25 m/s, 9.5 m/s, 11 m/s. The critical flow velocity can provide a reference for discharging liquid efficiently in engineering. Combining the flow process with corrosion studies, we identified the main cause and the sensitive areas of flow-accelerated corrosion. Finally, we proposed recommendations to prevent pipeline accelerated corrosion. Thus, the flow-accelerated corrosion of shale gas pipelines can be minimized. [ABSTRACT FROM AUTHOR]

Nonequilibrium many-body transient dynamics play an important role in the adaptation of active matter systems to environmental changes. However, the generic universal behavior of such dynamics is usually elusive and left as open questions. Here, we investigate the transient dynamics of vortex-like states in a two-dimensional active matter system that consists of self-propelled particles with alignment interactions subjected to extrinsic environmental noise. We identify a universal power-law scaling for the average lifetime of vortex-like states with respect to the speed of the self-propelled particles. This universal scaling behavior manifests strong robustness against the noise, up to the level where influences from environmental fluctuations are large enough to directly randomize the moving directions of particles. Direct experimental observations can be readily performed by related experimental setups operated at a decently low noise level. • A power-law scaling behavior exists for vortex-like states in active matters. • The scaling behavior manifests robustness against the environmental fluctuations. • This scaling behavior originates from the occurrence of "separated particles". [ABSTRACT FROM AUTHOR]

Abstract The self-accelerating Airy–Hermite–Gaussian (AiHG) and Airy–helical–Hermite–Gaussian (AiHHG) wave packets in strongly nonlocal nonlinear media (SNNM) are obtained analytically and numerically. The complex amplitudes of the AiHG and AiHHG wave packets are obtained by multiplying the self-accelerating Airy functions, the Hermite Polynomials and Gaussian functions. Furthermore, the different 3D spatiotemporal profiles and the photoelasticity can be obtained by selecting different values of the mode number, the chirp factor, the initial velocity, and the degree of the nonlocality. [ABSTRACT FROM AUTHOR]

Taking advantage of alternative expressions for potential vorticity (PV) in divergence forms, we derive balances between volume integral of PV and boundary conditions, that are then applied to practical computations of PV: • We propose a new method for diagnosing the Ertel potential vorticity from model output, that preserves the balances; • We show how the expression of PV can be derived in general coordinate systems. This is here emphasised with isopycnic coordinates by generalising the PV expression to the general Navier-Stokes equations; • We propose a generalised derivation for the Haynes-McIntyre impermeability theorem, which highlights the role of the bottom boundary condition choice (e.g. no-slip vs free-slip) and mixing near the bottom boundary for the volume integral of PV. The implications of balances between volume integral of PV and boundary conditions are then analysed for specific processes at various scales: • At large scale, we show how an integral involving surface observations (derived from satellite observations) is linked to the integral of PV within a layer (between two isopycnals). This surface integral can be calculated for models and observations and can be used for validation; • At mesoscale or sub-mesoscale, we analyse the relationship between net PV anomalies and net surface density anomalies for idealised vortices and 2D fronts. This can help determining vortex or jet structures for idealised studies or empirical methodologies; • We also confirm and integrate previous results on the modification of PV within a bottom boundary layer into a single diagnostic taking into account the effect of density and velocity modifications by diabatic processes along the topography and diapycnal mixing within the boundary layer. • Ertel potential vorticity (PV) expressions in divergence form improve PV diagnostics in models. • Balances are derived between volume integral of PV and boundary conditions. • Practical numerical computations of PV, preserving balances, are proposed. • The implications of balances are examined for selected processes. [ABSTRACT FROM AUTHOR]

Highlight • Sudden contraction into the inlets of two parallel jets was investigated with PIV. • Velocity vectors evolve with a position in the contraction. • The size and shape and position of vortices change with Reynolds number. • Turbulence started at the fast and slow flow partitions and intensifies with Reynolds number. Abstract The inlets to parallel rectangular jets are unique and a critical component of its design. A sudden contraction (contraction ratio = 4.2) of a vertically upward entry flow into two inlets has been investigated experimentally. Changes in velocity profile close to the inlets were measured, while the corner vortices, fluid separation and the development of axial and lateral turbulent intensities were observed from the result of particle image velocimetry analysis. The velocity profiles in the fluid adjacent to the inlets are independent of the Reynolds number, generally the same for similar geometries, concave but changes rapidly before finally adapting to the positions of the inlets. The radii of the corner vortices decreased and became elliptical with an increase in Re. Also, the detachment length shrunk by 60% when the Re was doubled. Lateral and axial turbulence increased and more fluid flowed parallel to the wall as Re increased. The trend and magnitude of the lateral to axial velocity agree with those of similar works. [ABSTRACT FROM AUTHOR]

Highlights • The three-dimensional dune wake are investigated by PIV. • The large-scale structure is responsible for the formation of separation region. • The intermediate-scale structure is more active near the separation region. • The intermediate-scale structure makes more contribution to Reynolds stresses. • The small-scale vortical structures decay quickly at the downstream. Abstract The three-dimensional wake structures behind a barchan dune model are investigated by the high-speed particle image velocimetry (PIV) at the Reynolds number of 5530. The measured velocity fields are first evaluated by time-averaged flow patterns and power spectra analysis. Then the one-dimensional orthogonal wavelet analysis is applied to reveal multi-scale turbulent structures and their corresponding second order statistics in the dune wake. The instantaneous multi-scale structures suggest that the large-scale structure is responsible for the formation of separation region. The intermediate-scale structure tends to be more active at the boundary of separation region, which may be due to the secondary vortex movement caused by the interactions between the wake and main flow. The appearance of small-scale vortices at the downstream of separation region indicates the breakdown process of large-scale vortices. The Reynolds stress and kinetic energy distribution suggest that the large-scale structures dominate the generation of turbulence in the dune wake. The lower kinetic energy contained in intermediate- and small- scale structures is considered to be related to smaller-scale interactions that reflect energy cascading phenomenon. The Reynolds shear stresses distributions suggest that the intermediate-scale structures also make significance in the separated boundary layer. As for small-scale structure, it is worthy to note that a region of high Reynolds shear stresses with an opposite sign is observed around the dune crest. The cross-correlation function of multi-scale structures suggest the quasi-periodicity of large-scale structure. The intermediate-scale structures also show a certain periodicity, however, such structures tend to be more unstable and the strength of them reduces as they travel downstream. When decreasing to small-scale, the vortical structures decays quickly at the downstream with larger convective velocity. This may indicate the breakdown process of large-scale vortices and the quick dissipation of small-scale vortices. [ABSTRACT FROM AUTHOR]

Stable and metastable vortex states in two-dimensional three-component Bose–Einstein condensates are studied in the presence of spin–orbit coupling. The ground states exhibit two skyrmion structures which respectively correspond to the d-skyrmion in antiferromagnetic or the F-skyrmion in ferromagnetic condensates. The half skyrmion and full skyrmion can be controlled by changing the strength of the spin–orbit coupling. We also find a stable composite vortex state which is associated to mixing of the ferromagnetic and antiferromagnetic manifolds. [ABSTRACT FROM AUTHOR]

Abstract A Czochralski melt flow encounters the effects of anisotropic body forces owing to the system rotation as well as significant streamline curvature due to inherent vortical structures and flow past curved surfaces. Two-equation eddy-viscosity models lack the ability to capture the flow anisotropy and curvature effects. Here we present the first study on the thermo-fluid characteristics of Czochralski melt using rotation and streamline curvature corrected Partially-Averaged Navier-Stokes (PANS) adaptations of the low- Re k-ε and SST k-ω models. The paper presents physical insights to the new PANS turbulence modelling approach highlighting improvements in the predicting capability of PANS models with the incorporation of rotation and curvature corrections. The PANS models showed good agreement with the results available in the literature (both experimental and computational). In addition for the PANS low- Re k-ε model it was observed that the prediction of the typical Czochralski melt flow structure in terms of shape, relative size and orientation of the characteristic cells improved with rotation and curvature corrections. Further thermal fluctuations and vortex cores also reduced in the melt in the case of the PANS low- Re k-ε model showing stabilization of flow. The corresponding rotation and curvature modification to the PANS SST k-ω model corrected the flow dynamics from a buoyancy dominated to rotationally driven along with an increase in the thermal fluctuations and vortex cores in the Czochralski melt resulting in a destabilization of the melt flow. Highlights • Rotation and Curvature corrections applied to low- Re k-ε and SST k-ω PANS models. • Similar thermal characteristics were observed in CZ melt for both PANS models. • Flow dynamics in PANS SST k-ω model corrected to rotation driven with correction. • For PANS low- Re k-ε model the typical CZ flow structure improved with correction. • Correction stabilized flow in low- Re k-ε and destabilized in SST k-ω PANS models. [ABSTRACT FROM AUTHOR]