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Copyright of China Petroleum Machinery is the property of China Petroleum Machinery Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The issue of uncertain roll angle and large angle of attack during the initial stage of launch has a significant impact on the initial attitude and control of canard‐controlled missiles. In this study, canard‐controlled missiles are employed to study the influence of multivortex structure present in the head under different roll angles at high angles of attack. The turbulence model was verified and used for simulation. The evolution of the multivortex structures behind the canard and their impact on the flow field and lateral force was investigated. The results show that the multivortex structure at the head forms a flow field structure dominated by two main vortices through vortices merging. When the geometry is symmetric, the symmetric vortices maintain a long symmetry region on the flow field, and the "X" shape shows higher flow field stability than the "+" shape. The asymmetric geometric structure produces two asymmetric main vortices, causing alternating steady separation and shedding of downstream vortices. This leads to alternating pressure fluctuations on the surface of the body, which are reflected in the lateral force through the integration of the pressure along the lateral direction. In contrast to the alternating shedding of separation vortices observed in a wingless configuration due to natural asymmetry, the asymmetrical main vortices induced by the asymmetry of canard cause alternant vortex shedding to occur earlier. With the increase of the angle of attack, the pressure difference of the head gradually dominated the lateral force, resulting in a drastic decrease in the lateral force coefficient. [ABSTRACT FROM AUTHOR]

A high-fidelity computational fluid dynamics and rigid-body dynamics coupling platform suitable for virtual flight simulation of dual-spin projectile is developed. Based on this platform, the influence of rotating canards on the trajectory following stability of the dual-spin projectile is studied. To accurately characterize the differential rotation effect of the dual-spin projectile’s fore and aft bodies, a slidingmesh algorithm is introduced into the in-house unstructured mixed grid flow field numerical simulation program HUND3D. By conducting axisymmetric rotational unsteady simulations of the dual-spin projectile and investigating the flow characteristics and aerodynamic properties under different canard rotation speeds, the dynamics mechanism of the trajectory following process is analyzed. Through the coupled solution of unsteady Reynolds-averaged Navier-Stokes equations and seven-degree-of-freedom rigid-body dynamics equations, virtual flight simulations of the dual-spin projectile with different curvature trajectories are realized. The dynamic mechanism of the trajectory tracking process is analyzed, and strategies for improving trajectory following stability by controlling the canard rotation speed based on the analysis of aerodynamic characteristics are studied. The research results indicate that the aerodynamic disturbances generated by canard rotation can significantly affect the lateral force and yawing moment of the projectile. By controlling the rotation speed of the fore canards to produce a yawing moment favorable for trajectory tracking, the trajectory following stability can be improved to a certain extent.

Copyright of Aero Weaponry is the property of Aero Weaponry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The rotary energy recovery device (RERD) plays an important role in reverse osmosis (RO) desalination; however, few investigations on the formation and influence of lateral force on the RERD rotor have been published. The transient characteristics of lateral force and its relationship with pressure distribution and fluctuation in the clearance were analyzed via computational fluid dynamics (CFD) simulation. The clearance pressure distribution and lateral force were quantified under different working conditions. The eccentricity of the rotor, resistance torque and decrease in the rotary speed due to the lateral force were simulated and they were found to change with flow rate and pressure of high-pressure outlet (PHO). A new rotary speed prediction method including the effect of PHO was developed. With the increasing flow rate or PHO, the stability of RERD declined. A design optimization direction was proposed. The variation trends of rotary speed, pressure in the clearance and its fluctuation were verified through experiment. This research provides an explanation why in practice the rotary speed decreases with increasing pressure. The conclusions obtained herein can be of great significance for future research on improving the stability and lifespan and reducing the maintenance consumption of RERD. [ABSTRACT FROM AUTHOR]

An overview of experimental and theoretical studies of the characteristics of maglev systems using high- temperature superconductors (HTSC) is presented. Materials used in maglev technologies, namely bulk superconductors and HTSC tape composites, are considered. The main experimental data obtained on both bulk and tape superconductors assembled in stacks of various configurations are demonstrated. The factors influencing the magneto-force characteristics are analyzed: geometric parameters, the influence of external alternating magnetic fields, temperatures, relaxation phenomena. A significant part of the review is devoted to the description of various methods for calculating maglev systems, including those based on stacks of HTSC composites. The features of thermal processes in maglev systems with cryocooler and nitrogen cooling are considered. General recommendations for the creation of optimal maglev systems based on tape HTSC composites are given. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The area of trapping the atoms or molecules using light has advanced tremendously in the last few decades. In contrast, the idea of controlling (not only trapping) the movement of atomic-sized particles using matter waves is a completely new emerging area of particle manipulation. Though a single previous report has suggested the pulling of atoms based on matter-wave tractor beams, an attempt is yet to be made to produce a lateral force using this technique. This article demonstrates an asymmetric setup that engenders reversible lateral force on an atom due to the interaction energy of the matter wave in the presence of a metal surface. Several full-wave simulations and analytical calculations were performed on a particular set-up of Xenon scatterers placed near a Copper surface, with two counter-propagating plane matter waves of Helium impinging in the direction parallel to the surface. By solving the time-independent Schrödinger equation and using the solution, quantum mechanical stress tensor formalism is applied to compute the force acting on the particle. The simulation results are in excellent agreement with the analytical calculations. The results for the adsorbed scatterer case find this technique to be an efficient cleaning procedure similar to electron-stimulated desorption for futuristic applications.

Background: Assessing the effect of scaler tip wear on the root surface roughness using piezoelectric ultrasonic scaling device under influence of various working parameters, i.e. power setting, lateral force, and instrumentation time. Materials and Methods: An experimental study was conducted using 160 single-rooted tooth samples divided into two groups of new (n = 80) and worn tips (n = 80). Samples were prepared to examine the root surface roughness after being instrumented by new and worn piezoelectric ultrasonic tips (8 new/8 worn) at different parameters. The erosion ratio (ER) of the new/worn tip was examined under an atomic force microscope and roughness over root surface was measured by a contact surface profilometer. One-way analysis of variance test, post hoc Tukey's test, and independent t-test were used for intragroup, pair-wise multiple comparisons and intergroup comparison of average roughness (Ra) value. Results: A statistically significant difference was found between the ER of new and worn scaler tips (P < 0.001). Intragroup comparison between subgroups 1 and 8 showed a higher Ra value in both the groups (P < 0.005). There was a significantly higher Ra value of worn tips compared to new tips (P < 0.05). Significantly higher mean Ra value was shown when lateral force changed from 50 g to 100 g (P < 0.005). Conclusions: Increasing value of power setting, lateral force, and instrumentation time caused more surface roughness in worn-out scaler tips compared to new scaler tips. Lateral force and instrumentation time proved to be a major factor influencing surface roughness. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shanghai Jiaotong University (Science) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The bending deformation can affect the lateral force of spinning projectiles with large aspect ratios, thus interfering with their flight stability. Based on the established spin–deformation coupling motion model, the unsteady Reynolds averaged Navier–Stokes (URANS) equations are solved to simulate the flow over a large−aspect−ratio projectile undergoing spin and spin−deformation coupling motion by using the dual−time stepping method and dynamic mesh technique, obtaining the lateral force. Furtherly, the flow mechanism is analyzed for the changed lateral force induced by the bending deformation. The results indicate that the variation of transient lateral force for the head of a projectile is consistent with that of the deformation−induced additional sideslip angle; affected by the deformation−induced compression wave and expansion wave, the time−averaged lateral force for the middle of a projectile will be increased at small angles of attack, but changed little at large angles of attack; at small angles of attack, the change trend of transient lateral force for the tail of a projectile is similar to that of additional angle of attack caused by the deformation; at large angles of attack, the characteristic of phase lag is presented between the transient lateral force for the tail of a projectile and the additional sideslip angle. [ABSTRACT FROM AUTHOR]

The rotary energy recovery device (RERD) plays an important role in reverse osmosis (RO) desalination; however, few investigations on the formation and influence of lateral force on the RERD rotor have been published. The transient characteristics of lateral force and its relationship with pressure distribution and fluctuation in the clearance were analyzed via computational fluid dynamics (CFD) simulation. The clearance pressure distribution and lateral force were quantified under different working conditions. The eccentricity of the rotor, resistance torque and decrease in the rotary speed due to the lateral force were simulated and they were found to change with flow rate and pressure of high-pressure outlet (PHO). A new rotary speed prediction method including the effect of PHO was developed. With the increasing flow rate or PHO, the stability of RERD declined. A design optimization direction was proposed. The variation trends of rotary speed, pressure in the clearance and its fluctuation were verified through experiment. This research provides an explanation why in practice the rotary speed decreases with increasing pressure. The conclusions obtained herein can be of great significance for future research on improving the stability and lifespan and reducing the maintenance consumption of RERD.

The purpose of this study was to investigate the lateral force and contribution of shoulder horizontal adductor and elbow extensor muscles activity during wide- and narrow-grip bench press (BP) in various conditions, such as resistance-trained/non-trained, concentric/eccentric, and muscle fatigue/non-fatigue. We measured the lateral force on the bar and the electromyographic (EMG) muscle activity of pectoralis major (PM) and triceps brachii (TB) during 10 RM BP with wide grip (81 cm) and narrow grip (40 cm) in seven resistance-trained men and seven non-trained men. The all-reps average of the lateral-to-vertical force ratio both in resistance-trained and non-trained subjects was about 30% outward for the wide grip and about 10% inward for the narrow grip. The EMG contribution ratio PM/TB shows no significant differences between narrow and wide grip in all evaluated conditions except in non-trained subjects' muscle fatigue eccentric phase. Both resistance-trained and non-trained subjects did not push the bar straight upward, and the EMG PM/TB was almost unchanged by hand width. The direction adjustment of the force on the bar that achieves almost the same muscle activity degree of the shoulder and elbow joints might be optimal BP kinetics. [ABSTRACT FROM AUTHOR]

This article develops three transverse rib setting schemes for a 20 m wide cantilever segmental box girder of a particular engineering bridge deck, analyzes the stress rules under loads such as dead load, live load, and temperature, and studies the lateral deformation characteristics of the three schemes under symmetrical and eccentric live load arrangements on the bridge deck. Research has shown that setting transverse ribs can significantly improve the transverse stress, crack resistance, and reduce vertical deformation of the cross-section. However, its effect gradually weakens with the increase in the number of transverse ribs. Considering the convenience and simplicity of construction, installing a transverse rib structure for the large cantilever section box girder in this project is recommended. [ABSTRACT FROM AUTHOR]

Background: Assessing the effect of scaler tip wear on the root surface roughness using piezoelectric ultrasonic scaling device under influence of various working parameters, i.e. power setting, lateral force, and instrumentation time. Materials and Methods: An experimental study was conducted using 160 single-rooted tooth samples divided into two groups of new (n = 80) and worn tips (n = 80). Samples were prepared to examine the root surface roughness after being instrumented by new and worn piezoelectric ultrasonic tips (8 new/8 worn) at different parameters. The erosion ratio (ER) of the new/worn tip was examined under an atomic force microscope and roughness over root surface was measured by a contact surface profilometer. One-way analysis of variance test, post hoc Tukey's test, and independent t-test were used for intragroup, pair-wise multiple comparisons and intergroup comparison of average roughness (Ra) value. Results: A statistically significant difference was found between the ER of new and worn scaler tips (P < 0.001). Intragroup comparison between subgroups 1 and 8 showed a higher Ra value in both the groups (P < 0.005). There was a significantly higher Ra value of worn tips compared to new tips (P < 0.05). Significantly higher mean Ra value was shown when lateral force changed from 50 g to 100 g (P < 0.005). Conclusions: Increasing value of power setting, lateral force, and instrumentation time caused more surface roughness in worn-out scaler tips compared to new scaler tips. Lateral force and instrumentation time proved to be a major factor influencing surface roughness.

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The lateral stability of superconducting magnetic levitation systems is critical to safe operation of maglev technologies. The article provides a horizontal stability investigation of suspension of a superconducting system with an object levitating between two magnetic bodies. The system consists of bulk high-temperature superconductors (HTSs) and permanent magnets (PMs). The numerical analysis is carried out for different designs of the system (an HTS suspended between two fixed PMs and a PM between two HTSs). The stability of levitation is studied with respect to small horizontal displacements from an equilibrium position. Based on the analysis of horizontal force gradients in basic traditional maglev systems, it is shown that during levitation in the gap, the lateral stability is mainly provided by the attractive interaction of the suspended object with the upper fixed body. As a result of modeling, united diagrams with regions of stable and unstable levitation have been obtained. They show stable suspension positions along the gaps of different sizes. [ABSTRACT FROM AUTHOR]

In order to study the flow characteristics of a nozzle with large expansion ratio and its influence on the force on the nozzle, ground cold flow test research and a fluid–structure coupling simulation analysis were carried out (maximum expansion ratio ε = 30.25). The variation and pulsation characteristics of the pressure near the measuring point area and the inlet pressure were obtained through experiments. Through the analysis of the peak-to-peak value and average value, it was found that the average pressure after separation increases by 90%, but the peak-to-peak value increases by about five times, indicating that the pressure fluctuation after separation is much larger than before separation. The separation flow field under cold flow conditions was simulated using the CFD commercial calculation software Fluent to verify the correctness of the numerical calculations. The fluid–structure coupling analysis was carried out on a large expansion ratio (maximum expansion ratio ε = 48) full-scale nozzle, and the structural deformation characteristics of the nozzle under the separation conditions were studied. The research results show that flow separation occurs in the nozzle with a large expansion ratio under ground conditions. Before the separation point, the pressure pulsation on the nozzle wall is small, and the turbulent pulsation effect is weak. After the separation point, the pressure pulsation increases, and the turbulent pulsation effect is enhanced. When the total pressure decreases, the separation area of the nozzle increases, and the separation flow field presents a strong asymmetry. Reducing the total inlet pressure by half resulted in approximately 50 times the lateral load. Under the combined influence of the ground conditions and low total pressure, the large lateral load caused by the asymmetry of the separation flow field will cause the deformation of the nozzle structure to increase by 5.5 times. This research provides an important reference for the design and experiment of nozzles with a large expansion ratio. [ABSTRACT FROM AUTHOR]

BACKGROUND: At present, there is a lack of research on the biomechanical properties of the medial and anterolateral anatomical locking plates of the tibia for the treatment of external rotation fractures of the tibia. OBJECTIVE: To compare stress distribution of the medial and anterolateral anatomical locking plates of the tibia for the treatment of external rotation fractures of the tibia using three-dimensional finite element analysis. METHODS: Tibia CT images of one healthy volunteer were selected. Digital technology was used to construct the medial and anterolateral locking plate model of the distal tibia. The model combination was set according to the principle of internal fixation. The axial compression force, valgus/varus force, and torsion force were given respectively to simulate the internal fixation force of human body under different stress conditions and analyze the displacement of the tibial fracture model. RESULTS AND CONCLUSION: (1) In the axial compression force, the maximum equivalent stress and the fracture surface displacement of the distal lateral plate were about 31.6% and 8.8% smaller than those of the distal medial plate. (2) In torsion-external rotation, the maximum equivalent stress was similar and the displacement of the fracture surface was also similar between the distal medial and lateral plates. (3) Under torsion-internal rotation, the maximum equivalent stress and torsional angular displacement of the fracture surface of distal lateral plate was about 23.8% and 65.3% smaller than those of the distal medial plate. (4) When subjected to valgus violence, the maximum equivalent stress and displacement of the fracture surface of distal lateral plate were about 38.2% and 86.5% smaller than those of distal medial plate. When subjected to varus violence, the maximum equivalent stress and the displacement of the fracture surface of distal lateral plate were about 4.8% and 7.6% smaller than those of distal medial plate. (5) In external rotation spiral fractures of the middle and lower tibia, distal tibial anterior lateral plate has better ability to resist axial, twist-clockwise rotation, varus and valgus violence. The distal lateral plate has more biomechanical advantages than the distal medial plate. [ABSTRACT FROM AUTHOR]

The thrust vector control of a rocket engine by disturbing the supersonic flow in its nozzle is used for missile development for various purposes in different countries. Disturbance of the supersonic flow in the jet engine nozzle can be caused by various obstacles on the nozzle wall: solid obstacle, liquid or gas jet, combinations of solid obstacle with injected jets. The simplest and most effective way to create a disturbance is to disturb it by setting a solid cylindrical obstacle on the nozzle wall. The high efficiency is explained by the lack of the working fluid consumption on board the aircraft to create a control force, or its minimum amount necessary to protect the obstacle from the high-temperature oncoming gas flow in the rocket engine nozzle. This paper presents the study results of gas flow simulation with cylindrical obstacle perturbation on the wall of the Laval rocket engine nozzle in its subsonic and supersonic parts. The optimal placement in the nozzle is determined to obtain the maximum lateral control force. As a result of research, it was found that the perturbation of a supersonic flow in a rocket engine nozzle by a cylindrical obstacle has practically the same character when its position changes along the length of the nozzle. In the subsonic part of the nozzle in the median plane, the perturbed pressure on the wall has a positive sign, and on the obstacle wall its sign-alternating. When an obstacle is in the subsonic part of the nozzle, the integral value of the lateral force is negative in comparison with positive for the supersonic part. [ABSTRACT FROM AUTHOR]

The branch hole is the key to ensure the long-distance drilling of directional hole along the target stratum, improve the coverage of directional drilling and accurately explore geological abnormal bodies. The principle, advantages and disadvantages of the main sidetracking branch technology in coal mine were analyzed. Taking the low speed grinding and hang sidetracking branch without hole bottom as the research object, the sidetracking branch mechanical model was established, and the calculation formula and influence law of the lateral force of the branch sidetracking was given; the dynamic process of hang sidetracking was analyzed, and the drilling points in the initial, middle and final stages of sidetracking were summarized; the numerical model of branch transition section stability analysis was established, the influence of coal and rock mass failure depth on the stability of branch transition section was studied, and the suggestions for safe drilling in branch transition section were given. The field application were carried out in Chengzhuang Mine with branch coal seam directional hole and Qidong Mine with comb floor directional hole, the maximum number of branches in a single hole is 77, the sidetracking success rate is 100% with the safety is 100%, which will provides a technical guarantee for the role of near horizontal directional hole in coal mine.

[Display omitted] • Unusual stick–slip fluctuation is observed in electrical conductivity of graphite. • The abnormal behavior is caused by the cross-talk effect of inhomogeneous probes. • It offers new physical interpretation of the lattice-resolved conductivity data. • It suggests a new way of imaging tiny friction forces on graphite surface. Electrical conductivity images of graphite surfaces are routinely obtained using scanning probe microscopy. Although the acquired conductivity maps often display a trigonal pattern with smooth variations, a "stick–slip" type of fluctuation has also been reported, where the local conductivity inversely correlates with the friction force during probe scanning. In this work, we revisit the lattice-resolved variations in local conductivity on graphite surfaces and reveal a new series of behaviors. Unlike previous observations, we demonstrate that local conductivity can exhibit in-phase, out-of-phase, or mixed-mode correlations with "stick–slip" lateral force signals. These behaviors are attributed to the cross-talk effect between interface contact conductivity and lateral force, induced by the inhomogeneous conductivity of the tip apex. This mechanism is experimentally validated, showing that local conductivity variations can switch within a single scan due to spontaneous changes in the conductivity of the tip. Our findings enhance the understanding of lattice-resolved electrical conductivity data on graphite surfaces and suggest a novel approach to amplify small lateral forces using inhomogeneous probe tips. [ABSTRACT FROM AUTHOR]

This study explores optimizing drag reduction in three-catamaran formations under different Froude numbers and configurations. Initially, the numerical methods and models employed in this study are introduced, followed by a grid convergence analysis to ensure the accuracy and reliability of the numerical simulations. The still water resistance of the Delft-372 catamaran is numerically calculated at different Froude numbers (Fr) and compared with experimental data, showing a strong correlation and validating the numerical approach. Subsequently, the flow field and wave height along the hull centerline of the catamaran are analyzed at Fr = 0.3, 0.4, 0.5, and 0.6. Focusing on three-catamaran formations, this study separately investigates the drag characteristics of tandem, parallel, and triangle configurations to reveal the influence mechanisms of different configurations. The computational results indicate that certain formation configurations and distances can reduce resistance for both the entire formation and individual catamarans at different speeds. Additionally, the lateral force, bottom pressure, and bow-stern wave heights experienced by catamarans in formation were analyzed to provide a comprehensive understanding of their hydrodynamic interactions. From the perspectives of drag reduction and safety, the tandem formation is most advantageous, followed by the triangle formation, with optimal spacing recommended for different speeds. To mitigate the adverse effects of lateral force, the spacing between catamarans in parallel formation should exceed 1 B. • Optimal configurations of catamaran formations for resistance reduction with different layouts and spacings are proposed. • Complex hydrodynamic interactions between catamarans are analyzed, which provides valuable insights. • The feasibility of resistance reduction and energy saving in medium- and high-speed catamaran formations is discussed. [ABSTRACT FROM AUTHOR]

The bending deformation can affect the lateral force of spinning projectiles with large aspect ratios, thus interfering with their flight stability. Based on the established spin–deformation coupling motion model, the unsteady Reynolds averaged Navier–Stokes (URANS) equations are solved to simulate the flow over a large−aspect−ratio projectile undergoing spin and spin−deformation coupling motion by using the dual−time stepping method and dynamic mesh technique, obtaining the lateral force. Furtherly, the flow mechanism is analyzed for the changed lateral force induced by the bending deformation. The results indicate that the variation of transient lateral force for the head of a projectile is consistent with that of the deformation−induced additional sideslip angle; affected by the deformation−induced compression wave and expansion wave, the time−averaged lateral force for the middle of a projectile will be increased at small angles of attack, but changed little at large angles of attack; at small angles of attack, the change trend of transient lateral force for the tail of a projectile is similar to that of additional angle of attack caused by the deformation; at large angles of attack, the characteristic of phase lag is presented between the transient lateral force for the tail of a projectile and the additional sideslip angle.

In this paper, mechanism of compliance steers for lateral force and self-aligning torque is studied for strut type front suspension, which is commonly used in front wheel drive vehicle with transverse engine. First, through qualitative consideration, it is clarified that both of the compliance steers for lateral force and self-aligning torque consist of changes in toe-angle of three modes. Mode I is the change in toe-angle due to difference of displacements of the points on steering knuckle. Mode II is the change in toe-angle due to rotation of the lower arm. Mode III is the change in toe-angle due to displacement of the upper support of the suspension. In addition, it is shown that effects of design specifications of the suspension on the modes of compliance steer for lateral force and those for self-aligning torque are different. Based on this consideration, guidelines for design of strut type front suspension in terms of compliance steers for lateral force and self-aligning torque are presented. Then, CAE analysis for a suspension model based on a commercial vehicle is performed to confirm validity of the qualitative consideration as well as to show that compliance steer for self-aligning torque can have significance greater than that for lateral force.

Microbial biofouling on polymer surfaces can lead to their biodeterioration. This may result in deterioration of the surface, leading to cracking and fracturing. Fungal spores from Aspergillus niger 1957, Aspergillus niger 1988 and Aureobasidium pullulans were tested to determine their strength of attachment on three surfaces, p(γ-MPS-co-MMA), p(γ-MPS-co-LMA) and spin-coated poly(methyl methacrylate) (PMMAsc), using lateral force measurements. The results demonstrate that A. niger 1957 and A. niger 1988 spores were most easily removed from the p(γ-MPS-co-MMA) surface, which was the surface with the highest Ra value. The A. niger 1957 and A. pullulans spores were most difficult to remove from the PMMAsc surface, which was the hardest surface. A. niger 1988 spores were the most difficult to remove from p(γ-MPS-co-LMA), the most hydrophobic surface. The results with A. pullulans were difficult to elucidate since the spores bound to all three surfaces and were removed with similar rates of force. The lateral force results demonstrate that spore attachment to a surface is a multi-factorial process, and independent surface and microbial factors influence spore binding. Thus, each environmental scenario needs to be considered on an individual basis, since a solution to one biofouling issue will probably not translate across to other systems. This article is part of the theme issue 'Nanocracks in nature and industry'. [ABSTRACT FROM AUTHOR]

Different types and quantities of freight cars will affect the marshalling forms of freight trains. In order to investi-gate the influence of the marshalling forms on the aerodynamic performance of freight trains under crosswind, three types of freight cars such as box cars, gondola cars and tank cars, were selected to marshal with locomo-tives. This paper used Detached Eddy Simulation method (DES) based on the SST k  ω turbulent model to simulate the aerodynamic performance of the freight train under crosswind. The wind speed, wind angle and train running speed were set as 25m/s, 45° and 100km/h respectively. The influence of different marshalling forms on the aerodynamic performance of the freight train such as aerodynamic drag and lateral force were calculated and compared. The results showed that the marshalling forms have significant effect on the aerody-namic drag and the maximum difference of the aerodynamic drag can reach 20.5%. Furthermore, the variations of the lateral force of the whole train and the locomotive are not apparent. The maximum difference is only 4.3% and 4.1% respectively. However, the changes of marshalling forms have obvious influence on the lateral force of each carriage. The maximum difference of the lateral force of the box car, gondola car and tank car is 17%, 20.1% and 24.1% respectively. The essential reason why the marshalling forms has a significant impact on the aerodynamic performance of the freight train is that there are obvious differences in the volume and shape struc-ture of each railway carriage. The large volume of box cars and the cavity structure of gondola cars make their position a key factor affecting the aerodynamic performance of freight trains. Among the six different marshalling forms selected in this paper, the best marshalling form is: locomotive--gondola car--box car--tank car. Both the aerodynamic drag of the train and the lateral force of the boxcar are the smallest by taking this marshalling form.

The purpose of this study was to investigate the lateral force and contribution of shoulder horizontal adductor and elbow extensor muscles activity during wide- and narrow-grip bench press (BP) in various conditions, such as resistance-trained/non-trained, concentric/eccentric, and muscle fatigue/non-fatigue. We measured the lateral force on the bar and the electromyographic (EMG) muscle activity of pectoralis major (PM) and triceps brachii (TB) during 10 RM BP with wide grip (81 cm) and narrow grip (40 cm) in seven resistance-trained men and seven non-trained men. The all-reps average of the lateral-to-vertical force ratio both in resistance-trained and non-trained subjects was about 30% outward for the wide grip and about 10% inward for the narrow grip. The EMG contribution ratio PM/TB shows no significant differences between narrow and wide grip in all evaluated conditions except in non-trained subjects’ muscle fatigue eccentric phase. Both resistance-trained and non-trained subjects did not push the bar straight upward, and the EMG PM/TB was almost unchanged by hand width. The direction adjustment of the force on the bar that achieves almost the same muscle activity degree of the shoulder and elbow joints might be optimal BP kinetics.

This article develops three transverse rib setting schemes for a 20 m wide cantilever segmental box girder of a particular engineering bridge deck, analyzes the stress rules under loads such as dead load, live load, and temperature, and studies the lateral deformation characteristics of the three schemes under symmetrical and eccentric live load arrangements on the bridge deck. Research has shown that setting transverse ribs can significantly improve the transverse stress, crack resistance, and reduce vertical deformation of the cross-section. However, its effect gradually weakens with the increase in the number of transverse ribs. Considering the convenience and simplicity of construction, installing a transverse rib structure for the large cantilever section box girder in this project is recommended.

Measurement while drilling (MWD) technology is important for obtaining downhole parameters. As an essential parameter in drilling engineering, lateral force provides a powerful reference basis for judging the downhole drilling direction. Although stress measurement technology has matured, research on downhole lateral forces, especially near-bit lateral forces during the drilling process in petroleum exploration, is lacking. Based on the force analysis of a short measurement circuit, the lateral force measurement value of a drill bit and centralizer was converted to a drill string's radial-bending-force measurement. Two perpendicular lateral force components were measured using strain gauge technology, a lateral force measurement theory model was established, and a set of MWD systems was designed according to the model. The systems' function was verified through laboratory and field tests, and the field-test data were successfully obtained in the field application. The test results showed that the tested MWD system had acceptable accuracy, stability, and reliability and had the application potential to measure lateral force in the drilling industry. This article provides a new idea to study lateral force while drilling, which is of great significance to oil-drilling exploration and development. [ABSTRACT FROM AUTHOR]

We present capillary grip-induced stick-slip motion, a nanoscale tribological effect, where the role of a nanoscale confined water meniscus formed between a buckled sharp tip and a glass or mica surface is addressed by shear dynamic force measurement. We obtained the effective elasticity, viscosity, conservative (elastic) and non-conservative (viscous) forces, energy dissipation, and lateral force using small oscillation, amplitude-modulation, and shear-mode quartz tuning fork-atomic force microscopy (QTF-AFM). We distinguished the conservative and non-conservative forces by investigating the dependence of normal load and relative humidity, slip length, and stick-slip frequency. We found that the confined nanoscale water enhances the lateral forces via capillary grip-induced stick-slip on a rough surface, resulting in an increase of static lateral force (3-fold for both substrates) and kinetic lateral force (6-fold for glass, 3-fold for mica). This work provides quantitative and systematic understanding of nanoscale tribology properties in humid ambient conditions and is thus useful for control of friction as well as characterization of tribology in nanomaterials and nanodevices. [ABSTRACT FROM AUTHOR]

In probabilistic analysis of lateral wheel–rail forces, the wheel–rail interaction is assumed to involve a modified useful process and a random process of telegraph signal type. The wheel's margin of stability is determined. [ABSTRACT FROM AUTHOR]

Particle Resolved Simulations (PRS) for freely evolving sphere suspensions at solid volume fractions (φ) between 0.1 and 0.4, Reynolds number Re from 10 to 300 and particle-fluid density ratios ρ s ρ f of 2, 10 and 100 are used to investigate the effect of Voronoi tessellation based particle local solid volume fraction (φ v) on particle drag and lateral forces. Findings reveal the instantaneous suspension mean drag force is positively correlated with the variance of φ v among particles in the suspension. It is also shown that using the conditioned instantaneous φ v of each particle in existing mean drag force correlations can significantly improve the prediction accuracy. Suspension mean lateral force ranges up to 60 % of the drag force while individual particles exhibit values as high as 90 % of the drag force. An instantaneous lateral force correlation is proposed based on suspension-averaged flow variables and φ v. [Display omitted] • Particle Resolved Simulations are performed for freely evolving sphere suspensions. • A Voronoi tessellation based local solid fraction is defined for each particle. • Suspension-mean drag force correlates positively with local solid fraction variance. • Using local solid fraction in drag correlations improves prediction accuracy. • The significance of lateral force is highlighted and its correlation is developed. [ABSTRACT FROM AUTHOR]

Due to the inadequate understanding of the lateral interaction in cable-saddle system especially from the perspective of sufficient wire-discretization, challenges in anti-slip design and evaluation persist, particularly affecting the development of multi-tower suspension bridges. This study proposes a numerical model for the cable-saddle system that can consider sufficient discretized steel wires through slicing. Large-scale model experiment and numerical modeling are performed, revealing the distribution and transmission of contact forces within the system. Key finds include the escalation of lateral pressure with depth, sharply decreasing at the bottom, and the absence of obvious contact between wires at the same layer. Subsequent parametric study using the sliced numerical model showcases that the model enables efficient parameterized modeling and in-depth analysis of the cable-saddle system; wire arrangement with higher aspect ratio yields higher lateral force, with lateral pressure tending towards a logarithmic distribution; and increasing the friction coefficient reduces lateral force, while using thinner wires increases it. Finally, a case study on a typical multi-tower suspension bridge demonstrates that incorporating vertical plates significantly enhances the anti-slip contribution of lateral force, presenting a promising solution to tackle anti-slip challenges; the existing lateral force formula overestimates the anti-slip safety, while the traditional mode neglecting lateral friction underestimates it, especially in presence of vertical plates, indicating limitations in their application. This study provides a valuable reference for the anti-slip design and evaluation of cable-saddle system in multi-tower suspension bridges through a rigorous numerical method. • Development of a sliced numerical model for the cable-saddle system that considers sufficient discretized steel wires. • Validation of the proposed model against the first large-scale direct model experiment. • Revelation of the lateral mechanical behavior and key parameters of the cable-saddle system. • Exploration of the normal forces and frictional mechanism within the cable-saddle system in presence of vertical plates. • Clarification of the applicability of four potential anti-slip evaluation modes. [ABSTRACT FROM AUTHOR]

A new Lateral Force Impact Tribometer (LFIT) is designed to quantify the dynamic friction of synthetic seat belt and D Ring Polymer (DRP) under transient conditions during the initial sliding period. LFIT simulates the sliding between two bodies subjected to a sudden lateral force applied, resulting in relative motion. Transient friction under suddenly applied initial acceleration conditions is obtained from the displacement response. LFIT overcomes stiffness concerns of most displacement-controlled tribometers in which the sensors and actuators influence the contact stiffness, nature of asperity interaction, and frictional characteristics. The displacement vs. time response showed the variation in displacement during the initial 0.3 mm sliding distance. LFIT is modelled as a spring-mass-Coulomb damper system applied for transient analysis. The effect of contact pressure on the transient Coefficient of Friction (CoF) is studied in the present work. This paper perhaps presents the first report that enables the capture of the friction transition within 10 ms from the start of sliding. [ABSTRACT FROM AUTHOR]

The hydraulic sliding-spool valve is a key component to control the flow rates and thus pressures in different hydraulic volumes. The lateral force on the spool is one of the important effects resulting from moving resistance. This paper presents research aimed at understanding the effects of radial flow force and static pressure upon the lateral force. The radial flow force is calculated from three types of control surfaces labelled with square land, 45° conical, and round curved surfaces, for discovering the effects of control profile, combined with inlet and outlet control conditions. The pressure difference effect is analyzed along with six cases under the same orifice opening, and the radial flow force is found to vary linearly with the pressure difference. The results also indicate that the radial force for the inlet control mode is less than that of the outlet control mode. The jet angle is discovered to not only be related to the annular orifice opening and gap clearance, but is also influenced by the flow direction and control surface profile. The static pressure is the predominant factor in the lateral force compared to the radial flow force. The results indicate that the static pressure variation on the surface of the cylindrical spool shoulder increased linearly with the inlet pressure; and two stagnation points can be observed in the case of the valve cavity with oil passages on the same section, and square land control edge profile. The lateral force on the spool increases with the pressure, and could reach to the maximum of 300 N, implying that this force should be taken into account in the selection of an actuator, especially in high pressure applications.

Purpose. One of the indicators of the track and rolling stock interaction, non-observance of which can result in a traffic safety violation, namely to derailment, is a condition for ensuring stability against the wheel flange climbing onto the rail head. The aim of this work is to create a methodology for practical engineering calculation of the resistance coefficient against the wheel flange climbing onto the rail head. The described methodology will have complete information both from calculation formulas and from reference materials, to eliminate the need to attract additional sources and special software. Methodology. The main objective of the implementation of this purpose is to bring the calculation of horizontal forces to the engineering level. Due to the complexity of the interaction process between the track and the rolling stock and the need to take into account a large number of factors that have an effect on the result, as a rule, complex dynamic models are used to determine horizontal forces. A possible solution lies in the assumption that for a specific type of rolling stock, the horizontal force can be calculated by linear dependence on the value of the unbalanced acceleration. For this, an analytical technique for calculating horizontal forces was used. Findings. The authors determined the missing coefficients for calculating the horizontal force depending on the unbalanced acceleration for some types of shunting locomotives and for a freight car taking into account its load level. Originality. In the work, scientific and practical approaches for the interaction analysis of the track and rolling stock in the horizontal plane acquired further development. Practical value. The proposed step-by-step methodology for calculating the stability coefficient makes it possible at the engineering level to carry out a practical analysis of ensuring the safety margin against the wheel flange climbing onto the rail head, which is necessary when investigating the causes of rolling stock derailment and for a number of other tasks related to movement in curved track sections.

Relocation or beating of the piston occurs due to the action of lateral force in the crank mechanism, which leads to an increase in friction forces and shock loads in conjunction with the sleeve. Ultimately, this affects the operation of the engine, its noise, vibration and leads to intensive wear of the piston skirt. Therefore, the study of issues related to improving the reliability of the engine of transport and technological vehicles is an urgent task of technical operation. The aim of the work is to increase the reliability of the engine of transport-technological machines by reducing vibration during its operation. The article discusses a method that allows to reduce shock loads in the piston-cylinder coupling at a low crankshaft rotational speed at maximum torque, which is typical for the main engine modes of a transport-technological and road-building machine. It is proposed that under maximum load conditions with a minimum speed of rotation, the value of the total force when passing through the top dead center at the end of the compression stroke be equal to zero. In order for the gas pressure force at the top dead center to be equal to the inertia force of the translationally moving masses, it is recommended that the engine be tuned to change the valve timing during a compression stroke, i.e. increase the angle of delay in closing the intake valve. In confirmation of the above, a calculation was made to determine the angle of delay in closing the intake valve using the example of the YaMZ-65202.10 engine. To fulfill the equality of the gas pressure force and the inertia force at the top dead center, the value of the real engine compression ratio was found, which was 12.5. Next, the angle of the inlet valve closing lag is determined for this mode, which is calculated to be 540 crankshaft rotation after bottom dead center (according to the technical characteristics of this engine, this value is 480). The calculated data may be the initial parameters for the calibration of the program embedded in the electronic control unit of the transport and technological machine.

In order to study the flow characteristics of a nozzle with large expansion ratio and its influence on the force on the nozzle, ground cold flow test research and a fluid–structure coupling simulation analysis were carried out (maximum expansion ratio ε = 30.25). The variation and pulsation characteristics of the pressure near the measuring point area and the inlet pressure were obtained through experiments. Through the analysis of the peak-to-peak value and average value, it was found that the average pressure after separation increases by 90%, but the peak-to-peak value increases by about five times, indicating that the pressure fluctuation after separation is much larger than before separation. The separation flow field under cold flow conditions was simulated using the CFD commercial calculation software Fluent to verify the correctness of the numerical calculations. The fluid–structure coupling analysis was carried out on a large expansion ratio (maximum expansion ratio ε = 48) full-scale nozzle, and the structural deformation characteristics of the nozzle under the separation conditions were studied. The research results show that flow separation occurs in the nozzle with a large expansion ratio under ground conditions. Before the separation point, the pressure pulsation on the nozzle wall is small, and the turbulent pulsation effect is weak. After the separation point, the pressure pulsation increases, and the turbulent pulsation effect is enhanced. When the total pressure decreases, the separation area of the nozzle increases, and the separation flow field presents a strong asymmetry. Reducing the total inlet pressure by half resulted in approximately 50 times the lateral load. Under the combined influence of the ground conditions and low total pressure, the large lateral load caused by the asymmetry of the separation flow field will cause the deformation of the nozzle structure to increase by 5.5 times. This research provides an important reference for the design and experiment of nozzles with a large expansion ratio.

A series of full-scale pushed out tests were performed on the Perfobond rib shear connector. The tests were designed to examine the performance of the Perfobond rib shear connector under different rib hole sizes and shapes, reinforcing bar sizes, rib thicknesses, as well as the presence of lateral forces. It has been revealed from the test results that the rib hole size and reinforcement diameter may not act independently, and the influence of one's size is actually dependent on the size of the other one. The lateral forces also affect the performance of the shear connector; for example, the capacity of the shear connector would be larger under compression than under tension. The existence of transverse pretension stress accelerated the cracking of concrete, leading to the strength and stiffness of concrete, perforated plate, and reinforcing rebars unable to fully exert their effect. In addition, the constraint effect of transverse stress improved the strength and stiffness of concrete and delayed the concrete cracking, bringing the strength and stiffness of concrete, perforated plate, and reinforcing rebars into full play, and resulting in a significant improvement in the shear capacity of Perfobond rib shear connectors. [ABSTRACT FROM AUTHOR]

A study of the operation of elastic joints with preset dependences of the restoring torque on the angle of rotation in the crank mechanism is presented. The principle of operation of the proposed joints is based on the movement of the elastic element between the guides of the calculated shape. The installation of such a joint with a preset characteristic between the strut and the crank enables obtaining a constant angular velocity of the crank. With the introduction of an elastic hinge between the crank and the connecting rod, the lateral force acting on the piston in the case of a constant angular velocity of the crank decreases significantly. By adding the counterweight properly, it is possible to obtain zero lateral force on the connecting rod for the entire crank revolution. [ABSTRACT FROM AUTHOR]