Transverse Motion Research Articles

Enhanced velocity and weight-bearing capability of piezoelectric viscous-slip actuators utilising a pentagonal flexible hinge configuration

Abstract This research presents a novel piezoelectric stick–slip actuator design that capable of achieving higher speeds and handling heavier loads. This addresses the requirement for improved performance in the precision engineering industry. The symmetrical configuration of the pentagonal displacement amplification flexible hinge structure produces the transverse motion. The pentagon’s deformable range is sufficiently broad to amplify the piezoelectric stack’s output displacement and convert it into the desired transverse output displacement. To enhance the load capacity of the piezoelectric stick–slip actuator, one can raise the coupling displacement of the driving foot output. The flexible hinge construction undergoes finite element analysis, and the simulation results meet the design assumptions. The structure has been enhanced to mitigate the potential occurrence of jamming. A prototype was constructed and subjected to rigorous testing to examine its performance. The testing results indicate that the highest attainable velocity is 15.8 mm s−1, with an impressive precision of 35.9 nm. Despite being subjected to a load of 308 g, the output displacement remains steady at 0.376 mm s−1. A comparative study of experimental and finite element simulation findings demonstrates the feasibility of the structural design.

Phase-modulation-induced reconfigurable rotating photonic lattices in atomic vapors.

We propose a method to prepare optically induced rotating hexagonal and honey-comb photonic lattices by employing the phase modulated three-beam interference in atomic vapors with electromagnetically induced transparency. The phase differences among the three beams are dynamically elaborated to synthesize the circular motion (in transverse dimensions) of waveguides in the photonic lattices. Further, we verify this model experimentally in the case of low-speed modulation. A weak Gaussian probe field is sent into the constructed helical photonic lattices to image their structures under electromagnetically induced transparency (EIT). The motion trajectories of the sites on the discretized output patterns exhibit repeated circles, advocating the formation of rotating lattices. By introducing phase modulations to involved beams, we provide a continent way for producing transverse motions in waveguide arrays with reconfigurability in rotational direction, radius, and speed. This work looks forward to promising applications in topological photonics with great popularity.

AGN STORM 2. IX. Studying the Dynamics of the Ionized Obscurer in Mrk 817 with High-resolution X-Ray Spectroscopy

We present the results of the XMM-Newton and NuSTAR observations taken as part of the ongoing, intensive multiwavelength monitoring program of the Seyfert 1 galaxy Mrk 817 by the AGN Space Telescope and Optical Reverberation Mapping 2 (AGN STORM 2) Project. The campaign revealed an unexpected and transient obscuring outflow, never before seen in this source. Of our four XMM-Newton/NuSTAR epochs, one fortuitously taken during a bright X-ray state has strong narrow absorption lines in the high-resolution grating spectra. From these absorption features, we determine that the obscurer is in fact a multiphase ionized wind with an outflow velocity of ∼5200 km s−1, and for the first time find evidence for a lower ionization component with the same velocity observed in absorption features in the contemporaneous Hubble Space Telescope spectra. This indicates that the UV absorption troughs may be due to dense clumps embedded in diffuse, higher ionization gas responsible for the X-ray absorption lines of the same velocity. We observe variability in the shape of the absorption lines on timescales of hours, placing the variable component at roughly 1000 R g if attributed to transverse motion along the line of sight. This estimate aligns with independent UV measurements of the distance to the obscurer suggesting an accretion disk wind at the inner broad line region. We estimate that it takes roughly 200 days for the outflow to travel from the disk to our line of sight, consistent with the timescale of the outflow's column density variations throughout the campaign.

A space-adiabatic theorem for longitudinal and transversal wave motion analysis of graded metamaterials

The use of graded metamaterials is widespread in the fields of wave manipulation and energy harvesting. However, they have the drawback of causing energy scattering after a certain period due to wave reflection or trapping, known as the rainbow effect, in some cases. To address this issue, we extend the adiabatic theorem to the spatial modulation field to mitigate the impact of the rainbow effect, thereby enhancing transmission at the interface of graded metamaterials. Firstly, an analytical expression for the limiting gradient in the space-adiabatic theorem is derived. Then, it is applied to study the longitudinal wave motion in a spring-mass with graded resonators (SMGR) system and the transversal wave motion in a beam with graded resonators (BGR) system. The numerical study demonstrates that if the spatial gradient of system properties is small enough to satisfy the adiabatic theorem, wave scattering can almost be neglected, and transmission will experience a significant increase compared to the non-adiabatic case. Finally, the critical boundary between adiabatic and non-adiabatic cases is determined using the fitting method. This study introduces a design strategy for graded metamaterials, offering opportunities for communication, sensing, energy harvesting, and various other applications.

Convolution Neural Network Development for Identifying Damage in Vibrating Pylons with Mass Attachments.

A convolution neural network (CNN) is developed in this work to detect damage in pylons by measuring their vibratory response. More specifically, damage detection through testing relies on the development of damage-sensitive indicators, which are then used to reach a decision regarding the existence/absence of damage, provided they have been retrieved from at least two distinct structural states. Damage indicators, however, exhibit a relatively low sensitivity regarding the onset of structural damage, further exacerbated by the low amplitude response to a variety of environmentally induced loads. To this end, a mathematical model is developed to interpret the experimental data recovered from a fixed-base pylon with a top mass attachment to transverse motion. Damage is introduced in the mathematical model in the form of springs corresponding to the cracking of the beam's lower end. Families of numerically generated acceleration records are produced at select stations along the beam's height, which are then used for training a CNN. Once trained, it is used to identify damage from acceleration records produced from a series of experiments. Difficulties faced by CNN in correctly identifying the presence/absence of damage in the pylon are discussed, and steps taken to improve the quality of the results are proposed.

Study of intrinsic-kT in the Parton Branching Method

The work presented here focuses on the production of Drell-Yan lepton pairs in hadron-hadron collisions with very low transverse momentum which is sensitive to the contribution from the non-perturbative transverse motion of partons inside hadrons as well as to the multiple soft gluon emissions which have to be resumed. To study the two contributions, we use Parton Branching Method which describes the evolution of transverse momentum dependent parton distributions and provides very precise predictions for inclusive observables such as the Drell–Yan cross section as a function of transverse momentum. In this study, we tune a parameter that describes the internal transverse motion of partons within hadron (intrinsic-kT) depending on the soft gluon contribution which is varied applying a lower limit to the transverse momentum of the emitted parton in branching up to 2 GeV. It will be shown that the parameter presented by the width of the Gaussian distribution increases with the minimal transverse momentum. This means that by reducing the contribution of soft gluons, more intense internal transverse motion is required (larger intrinsic-kT) to describe experimental data. Moreover, it was observed that the value of the intrinsic-kT increases with the collision energy and such a trend is more pronounced when the minimum transverse momentum of the parton at the branching is higher.

Hybrid piezo-triboelectric wind energy harvesting mechanism with flag-dragging the cantilever beam vibration

Hybrid power generators will improve the extraction of electrical energy from the wind to develop sustainable and eco-friendly self-powered wireless sensors. A novel piezo-triboelectric flag wind energy harvesting nanogenerator (P-FTENG) is proposed that consists of a piezoelectric cantilever beam and a triboelectric flag. The flag flutters in the wind, inducing vibration in the cantilever beam, thereby converting wind energy into electrical power with piezo and triboelectric effects. Based on the aerodynamic mechanism, a nonlinear flutter theoretical model is derived to evaluate the drag force and pressure of fluid separation on the piezo-triboelectric structure. Furthermore, this paper comprehensively elaborates on the transverse motion of the flag flutter caused by the airflow. The force from the transverse motion excites the cantilever beam. The power output of P-FTENG generation depends on various factors. The optimized flag-shaped configuration may activate the piezoelectric cantilever beam vibration and decrease the crucial flutter wind speed, according to test results. P-FTENG generates a voltage of around 17.8 V when the wind speed is 8.5 m/s. The cantilever beam energy harvester's PEH reaches 32 mW/m2, while Flag-TENG's output power density reaches 37 μW/m2, which charges capacitors and lights the array of LEDs. The hybrid piezo-triboelectric flag nanogenerator fluttering in the wind is promising for powering the function of a calculator or electronic thermometer/hygrometer sensor.

Propagating kink waves in an open coronal magnetic flux tube with gravitational stratification: Magnetohydrodynamic simulation and forward modelling

Context. In coronal open-field regions, such as coronal holes, there are many transverse waves propagating along magnetic flux tubes, which are generally interpreted as kink waves. Previous studies have highlighted their potential role in coronal heating, solar wind acceleration, and seismological diagnostics of various physical parameters. Aims. This study aims to investigate propagating kink waves, considering both vertical and horizontal density inhomogeneity, using 3D magnetohydrodynamic (MHD) simulations. Methods. We established a 3D MHD model of a gravitationally stratified open flux tube, incorporating a velocity driver at the lower boundary to excite propagating kink waves. Forward modelling was conducted to synthesise observational signatures of the Fe IX 17.1 nm line. Results. Resonant absorption and density stratification both affect the wave amplitude. When diagnosing the relative density profile with velocity amplitude, resonant damping needs to be properly considered to avoid a possible underestimation. In addition, unlike standing modes, propagating waves are believed to be Kelvin-Helmholtz stable. In the presence of vertical stratification, however, the phase mixing of transverse motions around the tube boundary can still induce small-scale structures, partially dissipating wave energy and leading to a temperature increase, especially at higher altitudes. Moreover, we conducted forward modeling to synthesise observational signatures, which revealed the promising potential of future coronal imaging spectrometers such as MUSE in resolving these wave-induced signatures. Also, the synthesised intensity signals exhibit apparent periodic variations, offering a potential method for indirectly observing propagating kink waves with current extreme ultraviolet imagers.

Constrained motion of self-propelling eccentric disks linked by a spring.

It has been supposed that the interplay of elasticity and activity plays a key role in triggering the non-equilibrium behaviors in biological systems. However, the experimental model system is missing to investigate the spatiotemporally dynamical phenomena. Here, a model system of an active chain, where active eccentric-disks are linked by a spring, is designed to study the interplay of activity, elasticity, and friction. Individual active chain exhibits longitudinal and transverse motions; however, it starts to self-rotate when pinning one end and self-beat when clamping one end. In addition, our eccentric-disk model can qualitatively reproduce such behaviors and explain the unusual self-rotation of the first disk around its geometric center. Furthermore, the structure and dynamics of long chains were studied via simulations without steric interactions. It was found that a hairpin conformation emerges in free motion, while in the constrained motions, the rotational and beating frequencies scale with the flexure number (the ratio of self-propelling force to bending rigidity), χ, as ∼(χ)4/3. Scaling analysis suggests that it results from the balance between activity and energy dissipation. Our findings show that topological constraints play a vital role in non-equilibrium synergy behaviors.

Distinguishing Extreme Precipitation Mechanisms Associated with Atmospheric Rivers and Nonatmospheric Rivers in the Lower Yangtze River Basin

Abstract This study investigates the disparity in quantitative moisture contribution and synoptic-scale vertical motion in the lower reaches of the Yangtze River basin (LYRB) for different extreme precipitation (EP) types, which are categorized as EP associated with atmospheric river (AR&EP) or EP associated with nonatmospheric river (non-AR&EP). To analyze moisture contribution, backward tracking using the Water Accounting Model-2layers is performed. In general, the remote moisture contribution is 9.7 times greater than the local contribution, with the ocean contribution being 1.67 times stronger than the land contribution. However, terrestrial and oceanic contributions obviously increase in the EP types, especially for oceanic contribution being double in magnitude. Notably, the west Pacific (WP) contribution emerges as the dominant differentia between the EP types, playing a crucial role in the AR formation. By solving the quasigeostrophic omega equation, the upper-level jet (ULJ) stream acts as the primary dynamic forcing for transverse vertical motion in AR&EP, while the baroclinic trough exhibits a relatively weaker influence. However, both systems have a nearly equal impact on vertical velocity in non-AR&EP. The enhanced shearwise elevation in the non-AR&EP type is the response of the stronger upper-level ridge over the Tibetan Plateau (TP), which induces enhanced Q vector, the divergence pointing toward the LYRB. However, the main dynamic difference is the location of ULJ, which serves as the trigger role although weak. Diabatic forcing proves to be the decisive factor for vertical motion development, the difference attributed to the released excessive latent heating with excess moisture contribution from the WP in AR&EP with enhanced precipitation. Significance Statement The main objective of this study is to investigate quantitative moisture contribution by applying Water Accounting Model-2layers and vertical motion attribution using the quasigeostrophic omega equation for extreme precipitation types based on the presence or absence of atmospheric river. Our findings reveal excessive moisture from the west Pacific serving not only as key in atmospheric river formation but also as the primary trigger for intensified diabatic vertical motion, inducing enhanced precipitation. The direction of strong winds in the north of the Tibetan Plateau holds crucial forecasting implications, which determine the location of the upper-level jet stream downstream. The transverse vertical motion, induced by the upper-level jet stream, plays the dominant dynamic role in both extreme precipitation (EP) types.

Analytical Framework for Tension Characterization in Submerged Anchor Cables via Nonlinear In-Plane Free Vibrations

Submerged tensioned anchor cables (STACs) are pivotal components utilized extensively for anchoring and supporting offshore floating structures. Unlike tensioned cables in air, STACs exhibit distinctive nonlinear damping characteristics. Although existing studies on the free vibration response and tension identification of STACs often employ conventional Galerkin and average methods, the effect of the quadratic damping coefficient (QDC) on the vibration frequency remains unquantified. This paper re-examines the effect of bending stiffness on the static equilibrium configuration of STACs, and establishes the in-plane transverse free motion equations considering bending stiffness, sag, and hydrodynamic force. By introducing the bending stiffness influence coefficient and the Irvine parameter, the exact analytical solutions of symmetric and antisymmetric frequencies and modal shapes of STACs are derived. An improved Galerkin method is proposed to discretize the nonlinear free motion equations ensuring the accuracy and applicability of the analytical results. Additionally, this paper presents an analytical solution for the nonlinear free vibration response of the STACs using the improved averaging method, along with improved frequency formulas and tension identification methods considering the QDC. Through a case study, it is demonstrated that the improved methods introduced in this paper offer higher accuracy and wider applicability compared to the conventional approaches. These findings provide theoretical guidance and reference for the precise dynamic analysis, monitoring, and evaluation of marine anchor cable structures.

Design and kinematics analysis of a parabolic cylinder deployment mechanism with modular over-constrained triangular pyramid

Space missions require novel mechanisms that can have compact form in complex space environments. This study proposes a modular triangular pyramid parabolic cylinder deployment mechanism. The modular deployable unit contains an over-constrained triangular pyramid deployable mechanism and a symmetrical trapezoidal Bricard linkage that drives the longitudinal and transverse motions of the mechanism. A cable net is added between two symmetrical linkages to form a parabolic cylindrical reflector and is analyzed by the force density method. The Denavit-Hartenberg (D-H) coordinate method is used to analyze the kinematic characteristics. Based on the analytical solution for the angular displacement, the degrees of freedom of the mechanism are derived from screw theory. Subsequently, the angular velocity and acceleration of the joint points are obtained. Finally, kinematic models of the modular triangular pyramid parabolic cylinder deployable mechanism are established, and the accuracy of the theoretical model is verified using a numerical method. This novel parabolic cylinder deployable mechanism will have a significant influence in aerospace domain. Crucially, the work has value to design deployment mechanism for parabolic cylinder antenna.

Large-amplitude transverse MHD waves prevailing in the Hα chromosphere of a solar quiet region revealed by MiHI integrated field spectral observations

The investigation of plasma motions in the solar chromosphere is crucial for understanding the transport of mechanical energy from the interior of the Sun to the outer atmosphere and into interplanetary space. We report the finding of large-amplitude oscillatory transverse motions prevailing in the non-spicular Hα chromosphere of a small quiet region near the solar disk center. The observation was carried out on 2018 August 25 with the Microlensed Hyperspectral Imager (MiHI) installed as an extension to the spectrograph at the Swedish Solar Telescope (SST). MiHI produced high-resolution Stokes spectra of the Hα line over a two-dimensional array of points (sampled every 0.066″ on the image plane) every 1.33 s for about 17 min. We extracted the Doppler-shift-insensitive intensity data of the line core by applying a bisector fit to Stoke I line profiles. From our time–distance analysis of the intensity data, we find a variety of transverse motions with velocity amplitudes of up to 40 km s−1 in fan fibrils and tiny filaments. In particular, in the fan fibrils, large-amplitude transverse MHD waves were seen to occur with a mean velocity amplitude of 25 km s−1 and a mean period of 5.8 min, propagating at a speed of 40 km s−1. These waves are nonlinear and display group behavior. We estimate the wave energy flux in the upper chromosphere at 3 × 106 erg cm−2 s−1. Our results contribute to the advancement of our understanding of the properties of transverse MHD waves in the solar chromosphere.

Thermal Hall effect and neutral spinons in a doped Mott insulator

In the pseudogap phase of the cuprate, a thermal Hall response of neutral objects has been recently detected experimentally, which continuously persists into the antiferromagnetic insulating phase. In this paper, we study the transport properties of neutral spinons as the elementary excitation of a doped Mott insulator, which is governed by a mutual Chern-Simons topological gauge structure. We show that such a chiral spinon as a composite of an S=1/2 spin sitting at the core of a supercurrent vortex, can contribute to the thermal Hall effect, thermopower, and Hall effect due to its intrinsic transverse (cyclotron) motion under internal fictitious fluxes. In particular, the magnitudes of the transport coefficients are phenomenologically determined by two basic parameters: the doping concentration and Tc, quantitatively consistent with the experimental measurements including the signs and qualitative temperature and magnetic-field dependence. Combined with the predictions of the spinon longitudinal transport properties, including the Nernst and spin Hall effects, a phenomenological description of the pseudogap phase is established as characterized by the neutral spinon excitations, which eventually become “confined” with an intrinsic superconducting transition at Tc. Finally, within this theoretical framework, the “order to order” phase transition between the superconducting and antiferromagnetic insulating phases are briefly discussed, with the thermal Hall monotonically increasing into the latter. Published by the American Physical Society 2024

Multi-terminal logic transmission via orthogonal currents controlling magnetic skyrmion motion in a perpendicular ferromagnetic multilayer nanotrack

Magnetic skyrmions are topologically nontrivial whirling spin textures with great potential for next-generation magnetic logic and memory applications as spintronic information carriers. The abilities to precisely manipulate skyrmion generation and motion using electric current are considered to be important issues for developing the high-efficiency skyrmion-based devices. In this paper, a skyrmionic logic device structure is proposed to realize the generation of Néel-type skyrmions from the topologically trivial domains. Micromagnetic simulations are employed to investigate the controllable skyrmion motions manipulated by the orthogonal current excitations in a perpendicular ferromagnetic multilayer nanotrack. The transversal skyrmion motion induced by the skyrmion Hall effect is balanced through introducing a y-axial current. A three-terminals logic output is achieved by adjusting the strength of currents along x and y directions. The interlayer coupling effect for stabilizing skyrmion nucleation is finely tuned via a ferromagnetic pinning layer in absent of the external magnetic field. It is found that both the perpendicular magnetic anisotropy and the Dzyaloshinskii-Moriya interaction are critical for the formation of stabilized skyrmions. The controllable skyrmion motion and multi-terminal information transmission offer a novel path for designing skyrmion-based logic and memory devices.

Plasma lensing interpretation of FRB 20201124A bursts at the end of September 2021

ABSTRACT When radio photons propagate through a non-uniform electron density volume, the plasma lensing effect can induce an extreme magnification to the observed flux at certain frequencies. Because the plasma lens acts as a diverging lens, it can extremely suppress the observed flux when aligned with the source. These two properties can theoretically cause a highly magnified fast radio burst (FRB) to become faint or even disappear for a period of time. In this paper, we interpret that the significant increase in burst counts followed by a sudden quenching in FRB 20201124A in September 2021 can be attributed to plasma lensing. Based on the one-dimensional Gaussian lens model, we search for double main-peak structures in the spectra just before its extinction on 2021 September 29. After the de-dispersion and de-scintillation procedures, we find eight bursts with double main-peaks at stable positions. There are three parameters in our modelling, the height N0, width a of the lens and its distance DLS to the source. We reformulate them as a combined parameter ${P}_0 \propto \left(\frac{a}{\mathrm{au}}\right)\sqrt{\frac{\mathrm{kpc}}{D_{\mathrm{LS}}} \frac{\mathrm{pc}\mathrm{cm}^{-3}}{N_0} }$. The frequency spectra can give an accurate estimation of P0 corresponding to $\left(\frac{a}{\mathrm{au}}\right)\sqrt{\frac{\mathrm{kpc}}{D_{\mathrm{LS}}} \frac{\mathrm{pc}\mathrm{cm}^{-3}}{N_0} } \approx 28.118$, while the time of arrival only give a relatively loose constraint on a2/DLS. Comparing with the observation dynamic spectra, we suggest that for a plasma lens in host galaxy, e.g. DLS ≈ 1 kpc, the width of lens can not be larger than 40 au. At last, we estimate the relative transverse motion velocity between the lens and source, $v\approx 98\left(\frac{a}{\mathrm{au}}\right)\mathrm{km\,s^{-1}}$.

Design and beam dynamics validation of a spiral FFAG accelerator for CSNS-II

The fixed-field alternating gradient (FFAG) accelerator, with its compact structure and the combined advantages of high energy from synchrotrons and high beam intensity from cyclotrons, offers unparalleled benefits in accelerating protons, heavy ions, and short-lived particles such as muons and unstable nuclei. The China Spallation Neutron Source plans to establish an FFAG accelerator with a diameter of 20 meters at the end of the negative hydrogen linac for various purposes, including experiments in nuclear physics and medical applications. For this design, a scaling scheme using spiral magnets as the basic focusing structure is investigated to provide the proton beam with kinetic energy ranging from 300 MeV to 600 MeV. We present the design results for the scaling FFAG accelerator and discuss the optimization of the cell tune. A detailed beam dynamics verification and discussion of the proposed FFAG accelerator lattice are presented using the ray-tracing code Zgoubi, including off-axis optical characteristics, large amplitude transverse motion, and full-cycle longitudinal acceleration. The FFAG accelerator is demonstrated to provide a large transverse and longitudinal acceptance for the tracking beam in the designed lattice. A new simulation code based on Python for the study of FFAG accelerator beam dynamics has been developed, and the corresponding verification results are also presented.

A site-resolved two-dimensional quantum simulator with hundreds of trapped ions.

A large qubit capacity and an individual readout capability are two crucial requirements for large-scale quantum computing and simulation1. As one of the leading physical platforms for quantum information processing, the ion trap has achieved a quantum simulation of tens of ions with site-resolved readout in a one-dimensional Paul trap2-4 and of hundreds of ions with global observables in a two-dimensional (2D) Penning trap5,6. However, integrating these two features into a single system is still very challenging. Here we report the stable trapping of 512 ions in a 2D Wigner crystal and the sideband cooling of their transverse motion. We demonstrate the quantum simulation of long-range quantum Ising models with tunable coupling strengths and patterns, with or without frustration, using 300 ions. Enabled by the site resolution in the single-shot measurement, we observe rich spatial correlation patterns in the quasi-adiabatically prepared ground states, which allows us to verify quantum simulation results by comparingthe measured two-spin correlations with the calculated collective phonon modes and with classical simulated annealing. We further probe the quench dynamics of the Ising model in a transverse field to demonstrate quantum sampling tasks. Our work paves the way for simulating classically intractable quantum dynamics and for running noisy intermediate-scale quantum algorithms7,8 using 2D ion trap quantum simulators.

Trailing vortex at drifting ship hull: a numerical study on wandering and turbulence

ABSTRACT Trailing vortices are commonly associated with so-called contrails in the sky. These show instability phenomena which manifest in transverse motions and sudden thickness changes. Aircraft aerodynamics considers this so-called far field whereas for naval hydrodynamics the near-field is of dominating interest. For the latter, vortices are intensively investigated at the propeller, but they emerge also at manoeuvring ship hulls or blunt stern shapes. And this is studied within the current paper: the major trailing vortex next to the KVLCC2 hull at large drift incidence. Numerical simulations with the SST-based IDDES model are conducted with OpenFOAM. The target is to reveal details of the vortex centre flow like the evolution of turbulence and the characteristics and consequences of vortex wandering. The results reveal a low-frequency broadband wandering motion next to a broad turbulent inertial subrange and that about two thirds of resolved TKE can be attributed to wandering.

Exploring transverse particle motion in rotary drums: DEM analysis of the influence of cross-shaped internals on material transport

This study investigates the impact of lifters and cross-shaped internals on the transversal movement of wooden spheres within rotary drums. Utilizing Discrete Element Method (DEM) simulations, the research evaluates the influence of these internal configurations on evolving bulk porosity, particle trajectories and residence time of particles in the central area of the drum. The study analyzes three distinct internal geometries and the influences of parameters such as drum rotational speed, drum fill level, and particle water content. Analysis of the simulation results shows that the mean bulk porosity increases by 4% for a single internal cross and by 7% for four internal crosses compared to a configuration without internals. Additionally, it is observed that the residence time for particles in the center of the drum increases by an average of 2.5 times for a single internal cross and 5.5 times for four internal crosses compared to a configuration without internals.