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Buried pipelines subjected to permanent ground deformations (through, e.g., earthquake-induced liquefaction or fault rupture) often experience widespread damage. Regardless of the direction of ground movement, pipelines tend to respond and experience damage axially due to their directional stiffness characteristics. In addition, case studies and previous testing have shown that damage is concentrated at the pipe joints due to their lower strength compared with a pipe barrel. Previous testing has also shown that axial forces increase significantly when pipe connections have jointing mechanisms, such as coupling restraints, with larger diameters than the pipe barrel alone. These enlarged joints act as anchors along the pipe, increasing the soil resistance at these locations. Current methods for predicting the axial force along a pipe underpredict the force demands and oversimplify the mechanics of soil resistance on the joint face. This study conducts a series of 12 pipe-pull tests in a centrifuge, varying joint diameter and burial depth, to quantify the axial forces developed. A strong linear correlation was observed between the soil resistance on a joint face and the joint surface area and burial depth. The study also proposes an analytical solution based on pullout capacity design equations for vertical anchor plates as a function of soil and pipe joint properties. The proposed solution to calculate joint resistance is in good agreement with the centrifuge tests performed for this study and previous full- and model-scale experiments. The proposed prediction equation is anticipated to have future applications to other buried structures because it is based on mechanisms of passive resistance commonly encountered in underground structures and lifelines. [ABSTRACT FROM AUTHOR]

The accuracy of the constitutive model affects the precision of the finite element analysis. Four advanced sand constitutive models—the DM04 model, the SANISAND-MS model with memory surface (MS), the SANISAND-Sf model with semi-fluidized state (Sf), and the SANISAND-MSf model with both memory surface and semi-fluidized state—are examined in this article based on a comparison of simulation and experiment results of element tests. First, four constitutive models are implemented in OpenSees, and the constitutive models are calibrated based on the cyclic loading experiments of Karlsruhe fine sand. After that, the advantages and disadvantages of four constitutive models under different test conditions are analyzed. Finally, the finite element model of the LEAP-UCD-2017 (Liquefaction Experiments and Analysis Project, University of California Davis, 2017) centrifuge test is established to evaluate the performance of the four constitutive models for solving boundary value problems. It is found that the SANISAND-MSf model can well reproduce the undrained cyclic properties. [ABSTRACT FROM AUTHOR]

Understanding xylem embolism formation is challenging due to dynamic changes and multiphase interactions in conduits. Here, we hypothesise that embolism spread involves gas diffusion in xylem, and is affected by time. We measured hydraulic conductivity (Kh) in flow‐centrifuge experiments over 1 h at a given pressure and temperature for stem samples of three angiosperm species. Temporal changes in Kh at 5, 22, and 35°C, and at various pressures were compared to modelled gas concentration changes in a recently embolised vessel in the centre of a centrifuge sample. Temporal changes in Kh were logarithmic and species‐specific. Maximum relative increases of Kh between 6% and 40% happened at 22°C for low centrifugal speed (<3250 RPM), while maximum decreases between 41% and 61% occurred at higher speeds. These reductions in Kh were experimentally shown to be associated with a temporal increase of embolism at the centre of centrifuge samples, which was likely associated with gas concentration increases in recently embolized vessels. Although embolism is mostly pressure‐driven, our experimental and modelled data indicate that time, conduit characteristics, and temperature are involved due to their potential role in gas diffusion. Gas diffusion, however, does not seem to cover the entire process of embolism spread. [ABSTRACT FROM AUTHOR]

Infestations of ambrosia beetles in the tribe Xyleborini (Coleoptera: Scolytinae) are associated with economic losses to horticultural trees due to branch die‐back and tree death. Ethanol is a key attractant used for monitoring flight activity. Trapping experiments were conducted in woodlots in Ohio, USA, and Veneto, Italy, to characterize the effect of ethanol release rate on captures of Anisandrus maiche, Xyleborinus saxesenii, Xylosandrus crassiusculus and Xylosandrus germanus. In Ohio (2019, 2020 and 2021) and Italy (2021), traps were baited with centrifuge tubes that were modified to achieve ethanol release rates of 0.1–13.2 g/day. In Ohio (2022), traps were baited with varying quantities of manufactured lures to achieve release rates of 0.02–1.4 g/day. There was no consistent relationship between ethanol release rate and trap captures for the modified centrifuge tubes. In nine of sixteen analyses, traps baited with the centrifuge tubes releasing ethanol at 1.1 g/day or higher collected more A. maiche, X. saxesenii, X. crassiusculus and X. germanus than traps baited with centrifuge tubes releasing 0.1 g/day. In contrast, the manufactured lures releasing 0.1–1.4 g/day attracted more A. maiche, X. saxesenii, X. crassiusculus and X. germanus than lures releasing 0.02–0.05 g/day. This comprehensive study provides important insights into monitoring tactics for ambrosia beetles along with implications for optimizing ethanol‐baited traps as part of a ‘push‐pull’ strategy whereby repellents are used to ‘push’ beetles away from vulnerable trees and attractants are used to ‘pull’ them into annihilative traps. [ABSTRACT FROM AUTHOR]

Long-term heave of basement slabs is a significant problem in cities with overconsolidated clay, such as London. There is a dearth of data to calibrate the methods commonly used by designers to predict heave displacement and swell pressure. This paper presents results from two centrifuge tests aimed at reproducing the phenomenon of long-term basement heave. Reduced scale models of rectangular basements with different slab thicknesses underlain by overconsolidated clay were tested, to investigate the effect of base slab stiffness on heave behaviour. The centrifuge tests provided measurements of the profiles of vertical displacement, bending moments in the slab and contact pressure at the slab–soil interface. This is the first geotechnical centrifuge study to provide simultaneous measurements of vertical displacement and swell pressures during long-term basement heave. Whereas the flexible basement underwent significant differential heave and almost complete relaxation of swell pressures, the stiff basement generated large swell pressures and consequently large bending stresses. These results confirm that the prediction of high heave pressures is a self-fulfilling prophecy: a basement slab with high stiffness will beget large swell pressures. The experimental measurements of swell pressure and heave were compared to predictions by a simplified non-linear method of heave calculation. The simplified non-linear method produced acceptable predictions of total heave. [ABSTRACT FROM AUTHOR]

Underground transportation systems often involve multiple tunnels constructed closely together. Previous studies mainly focus on interaction between circular tunnels; by contrast, interaction mechanisms involving non-circular tunnels are not well understood. In this study, four physical three-dimensional centrifuge tests were performed in dry sand, simulating the response of existing circular and horseshoe-shaped tunnels to a newly excavated tunnel. Two different ratios between pillar depth and tunnel diameter (P/D) of 0.5 and 2.0 were considered. Furthermore, three-dimensional numerical back-analyses considering small-strain stiffness were undertaken. Results reveal that the ground settlement above an existing horseshoe-shaped tunnel is less sensitive to pillar depth than for circular ones. Furthermore, for P/D = 0.5, the existing horseshoe-shaped tunnel experiences both vertical and horizontal compression; more stress reduction occurs vertically than horizontally. A circular tunnel for the same pillar depth becomes compressed vertically but elongated horizontally; stress reduction around the existing circular tunnel is less vertically than horizontally. However, for P/D = 2.0, both types of tunnel become elongated vertically and compressed horizontally because of a larger reduction in vertical stresses than horizontal ones. These results demonstrate that both pillar depth and shape profoundly affect tunnel deformation mechanisms. [ABSTRACT FROM AUTHOR]

Due to insufficient backfilling and compaction, voids existing around the bottom of a buried pipe can have a negative effect on the mechanical behavior of the pipe. Expanded polystyrene (EPS) has been widely utilized in civil engineering as fill, backfill, moisture cutoff, and impact mitigation materials for falling rocks because of its light weight and workability. In this study, centrifuge model tests were conducted in order to investigate the possibility of pipe failure when voids existed around the bottom of the buried pipe, and the effect of installing EPS blocks as a countermeasure. In the test, a model polyvinyl chloride (PVC) pipe having a diameter of 140 mm was buried in the dry sand and loaded at the ground surface in a centrifugal field of 21G. Cases with voids around the bottom of the buried pipe and with EPS blocks were studied, and the differences in the pipe mechanical behavior under standard backfill conditions were discussed. The loading conditions and the shape of the EPS were varied. The test results showed that the loss of soil around the bottom of the pipe caused a stress concentration by a factor of more than 2.5 compared to the typical burial condition, and could directly cause pipe failure. In addition, it is clear that EPS installation was an effective countermeasure to avoid the risk of insufficient compaction, because it did not significantly affect pipe deformation and strain distribution, although the earth pressure tended to concentrate slightly at the bottom of the pipe. Practical Applications: Pipelines that are buried in the ground usually need to be backfilled uniformly with soil around the pipe. However, due to difficulties in construction, the backfilling and compaction may be insufficient on the bottom sides of the pipe, resulting in voids or localized low-density areas. In this study, centrifuge model tests were conducted to investigate the behavior of pipes buried in such nonuniform ground and the effectiveness of a countermeasure to install expanded polystyrene foam (EPS) blocks as a foundation instead of backfilling with soil. In the tests, a 150-mm-diameter polyvinyl chloride (PVC) pipe was buried in a container, and the strain of the pipe was measured in detail when a vertical load of up to 140 kPa was applied to the ground surface in a 20G centrifugal force field. As a result, when the soil in the lower part of the pipe is not uniform, a large strain is concentrated at the bottom of the pipe, which may lead to the pipe failure. Then, when EPS was installed, no large strains were measured, indicating that EPS installations are effective as a countermeasure. [ABSTRACT FROM AUTHOR]

Microbial-induced calcium carbonate precipitation (MICP) is an emerging in situ grouting technology for sand ground improvement, slope stability, and subgrade reinforcement, featuring rapid implementation and low energy consumption. The precipitated calcium carbonate crystals can rapidly fill and cement sand particles so as to form a new soil structure that effectively reduces liquefaction sensitivity and dynamic damage. The centrifuge shake table test is an effective method for simulating liquefaction of sandy soil layers under shear wave excitation. Many studies have been conducted on this topic in recent years. However, the study on dynamic response, especially the liquefaction resistance of MICP-cemented sands by centrifuge shake table tests, is rare. In order to investigate the cementation effect of microbial treatment, centrifuge shake table tests were performed on two models, i.e., untreated and MICP cemented sand model. The test results indicated that, compared with untreated sand model, the liquefaction resistance of the MICP model was significantly improved in terms of acceleration response, shear stiffness, stress–strain relationship, and ground surface settlement. This study contributes to a better understanding of the mechanical law in the liquefaction process and enriches the engineering application of microbial grouting treatment of sand foundation prone to liquefaction. [ABSTRACT FROM AUTHOR]

Geotechnical centrifuge tests were conducted to examine the influence of invert voids and surface traffic loads on 1400 mm diameter reinforced concrete pipes buried with a shallow soil cover depth of 700 mm. Void formation beneath the pipe was simulated during centrifuge testing. The test results revealed that before void formation, the surface load directly above the middle of the pipe caused a significant increase in not only the circumferential bending moments but also the longitudinal bending moments, the latter of which was considerable and could not be ignored. Void formation beneath the middle of the pipe led to a reduction in both the circumferential bending moments and longitudinal bending moments at all measuring positions, i.e., crown, springline, and invert. The most significant reduction occurred at the invert, and there was even a reversal in the sign of the invert longitudinal bending moment. A comparison was made between centrifuge tests with erosion voids and surface loads at different horizontal positions, which had a marked influence even when the positions differed by half a pipe length. Joint rotation played an important role in relieving large bending moments of pipe barrels in a jointed pipeline when the void and surface load were located at the joint. [ABSTRACT FROM AUTHOR]

Ground losses due to tunneling would induce settlement of nearby raft foundations. To study the change in behavior of the raft foundations over time due to tunnel excavation in soft clay, a series of centrifuge model tests were conducted. The results reveal that the raft stiffness has a significant influence on the development of the gap between the raft and the ground. The width of the gap beneath the flexible foundation would increase over time, leading to a further increase in tensile strain after excavation, whereas the gap for raft foundations with a large stiffness would reduce with time, causing a gradual decrease in tensile strain. The modification factor (MF) design approach is also evaluated with the test results and demonstrates that the MF design approach would underestimate the tensile strain of the flexible raft and provide a relatively conservative prediction for larger stiffnesses. [ABSTRACT FROM AUTHOR]

Geosynthetic-reinforced and pile-supported embankments (GRPSEs) encompass two core components of the aforementioned reinforced embankment and the underlying composite foundation. Previous centrifuge modeling of GRPSEs generally simplified or omitted the key aspects related to the core components, which can weaken the similarity of working performance between models and prototypes. In the current study, to accurately investigate the effects of the change of pile arrangement on the overall working mechanism of GRPSEs, two groups of centrifuge model tests on GRPSEs (Groups A and B with different pile cap sizes and pile spacings) were conducted by taking into account the similarity in design of materials, geometry, and pile‒soil friction. Without simplifications and omissions of the core aspects of the composite foundation, the test models involve the embankment slope, geotechnical reinforcement, large-diameter cast-in-situ concrete pipe (PCC) piles, and soft soil foundation. It has been verified that increasing the area replacement ratio by expanding the pile-cap area and enlarging the pile spacing is an economical way to reduce the final settlement and postsettlement, allowing for more loading to be concentrated on the PCC piles with a lower pile-soil stress ratio. Additionally, the influences of the 1g model preparation and g-ring loading method were analyzed and discussed. The subsurface settlements during the embankment loading stage, as well as the total rebound deformation, were recorded, and it was found that, based on the four-stage global settlement characteristics investigation, the settlement in the embankment construction stage and the final settlement are both overestimated. This study provides essential insights into the influence of modeling stress history on the deformation in centrifuge testing and serves as a reference for the pile arrangement design of GRPSEs. [ABSTRACT FROM AUTHOR]

This study presents the analysis and modeling of the optimal connection between an asynchronous three-phase electrical induction motor and a horizontal centrifuge used in olive oil extraction. The simulation, carried out using the well-established Simscape Electrical by Matlab R2024a, offers the advantage of reducing the purchasing cost of the electronic drivers and electric motors to be tested. Different connection cases among the electronic motor driver, the electric motor, and the horizontal centrifuge were examined. The findings indicate that the oversizing of the electric motor is required to increase the machine efficiency and to reduce the overall specific energy consumption; however, the asymptotic behavior of the specific energy consumption, being related to the motor power, places a limit on the motor oversizing. Indeed, raising the motor power reduces the specific energy consumption; however, this effect can be unimportant if considering the higher cost involved in purchasing both the electrical motor and the electronic motor driver. The results show that an overall percentage saving of specific energy consumption of 3.1% and 4.0% can be achieved with a slight (7.5 kW) and a medium (11 kW) oversizing of the electric motor, respectively. [ABSTRACT FROM AUTHOR]

The separation of the 92Mo and 100Mo isotopes from the natural composition to the 99.99% enrichment level in a three-section squared-off cascade with 200 centrifuges was investigated. The parameters of this cascade were optimized using the 3SQC–PSO and 3SQC–GOA codes and the PSO and GO algorithms. The objective function of the indicated optimization codes is to simultaneously maximize the cascade capacity, the recovery factor, and the D-function. The results obtained show that the separation of the 92Mo and 100Mo isotopes should be done in two and one separation steps, respectively. A single cascade of most suitable configuration for the separation of both the 92Mo and 100Mo isotopes is proposed. The recovery separations of the 92Mo and 100Mo isotopes in this cascade comprise 92 and 95%, respectively. [ABSTRACT FROM AUTHOR]

A method has been developed to calculate a squared-off cascade with an arbitrary number of external flows by varying the cuts of partial flows of the stages and minimizing the deviations of the calculated feed flows of the stages from specified flows. To minimize the deviations of the flows, a honeybee-colony algorithm ensuring a required accuracy in determining the parameters of the cascade was used. Based on a computational experiment on separation of molybdenum hexafluoride, the high efficiency of the method for concentrating isotopes with an extreme mass number has been shown. [ABSTRACT FROM AUTHOR]

In this study, centrifuge model tests were carried out to investigate the lateral response of single pile in coral sand foundation. The load–displacement relationships, pile deflections, bending moments, the changes in horizontal soil pressure, the predicted particle crushing behaviors, and p-y curves were compared and discussed in detail to study the influence of pile diameter and vertical load. Test results show that increasing diameter is the most direct and effective method to improve the horizontal bearing capacity of pile; the presence of vertical load would lead to an increase of bending moment and lateral displacement of the pile due to P-Δ effect and an improvement in soil resistance due to the vertical compression effect; the influence of particle breakage behavior of coral sand was not significant. In addition, the applicability of the existing p-y models for the coral sand foundation was systematically evaluated. According to the comprehensive analysis of the stress state of sand around pile, the evolution of soil resistance with depth was determined, which can be simulated by a power function. Based on the centrifuge test results, a modified p-y model for coral sand was proposed, and its rationality and applicability in predicting pile–soil responses were validated systematically. [ABSTRACT FROM AUTHOR]

Predicting the separation performance of decanter centrifuges is challenging due to dynamic events within the apparatus. Current methods for designing decanter centrifuges rely on simplified models, often leading to inaccuracies. Consequently, manufacturers must perform time‐intensive pilot scale experiments to derive their own correction factors. Growing computing power sparks interest in alternative modeling strategies. Grey box models (GBM) combine mechanistic white box models (WBM) and data‐driven black box models (BBM), with the optimal structure (parallel or serial) varying by application. For modeling decanter centrifuges, we propose a serial GBM that comprises an artificial neural network that outputs unknown material parameters into a first‐principle multi‐compartment model. Comparing this approach to alternative data‐driven modeling strategies (pure BBM, parallel GBM), we conclude that the serial GBM excels in terms of extrapolation, prediction ability, and transparency while also enabling a better comprehension of the separation process. [ABSTRACT FROM AUTHOR]

An experimental campaign is conducted on a 100g centrifuged monopile model, impact driven, into saturated dense sand, down to three embedding depths, corresponding to three slenderness ratios of 5, 4 and 3. These models are instrumented with optical fibres to measure the bending moment profile along the monopile. A new method is developed to determine the experimental soil reaction curves by considering the distributed moment part from the measured bending moment. This distributed moment is assessed by the one-dimensional finite-element (1D FE) model of the PISA (pile soil analysis) method. The key features of this study are: (a) the monopile behaves from pure rotation to combined rotation–flexure as the slenderness ratio is enhanced from 3 to 5, inducing a less pronounced linear rotation–deflection response at ground level; (b) although the distributed moment assessed in the PISA project is very low, the developed method is useful to explore the experimental local behaviour of laterally loaded monopiles; (c) the 1D FE PISA model captures reasonably well the overall behaviour of laterally loaded centrifuged driven monopiles, even if it is less accurate for the local behaviour. [ABSTRACT FROM AUTHOR]

This study conducted five centrifuge model tests to investigate the deformation characteristics of the Geosynthetics Reinforced Soil (GRS) abutments under vertical loads, considering the setback distance a b and beam seat width B as two major influencing factors. Test results show that a linear correlation existed between the maximum lateral facing displacements D L and the maximum settlements at the top of the GRS abutments D v. The a b and the B had different effects on the deformation characteristics of the GRS abutments as well as the relationship between the D L and the D v. The total volumetric strains of the GRS abutments were smaller than 0.3% for all the cases investigated in this study, indicating that it was reasonable to use the assumption of zero-volume change for the deformation calculation of the GRS abutments. This study proposed an improved semi-empirical method to describe the relationship between the D L and the D v. Centrifuge test results and data collected from the literature were used to validate the improved method. It was concluded that the improved method had the advantage of considering the effects of the a b and the B separately and therefore significantly improved the prediction accuracy of the deformations of the GRS abutments. • This study conducted five centrifuge model tests to investigate not only the lateral facing displacements and the settlements at the top of the GRS abutment under vertical loading but also the volumetric deformations which correlate both the lateral and the vertical deformations. • Based on the centrifuge test results and data collected from the literature, this study proposed and verified an improved semi-empirical method to describe the linear correlation between the maximum lateral facing displacements and the maximum settlements of the GRS abutments. • The improved method had the advantages of considering the effects of the setback distance and the beam seat width separately and significantly improves the prediction accuracy of the deformations of the GRS abutments induced by vertical loads. [ABSTRACT FROM AUTHOR]

The role of wall facing is crucial in the design of MSE walls. This study employed two centrifuge model tests specifically designed to analyze walls with two distinct facing types: full-height panel facing and modular block facing. Additionally, surcharge loads were applied to these MSE walls to simulate real-world conditions. The findings from these tests revealed that MSE walls with full-height panel facing exhibited superior performance under the combined effects of self-weight and surcharge loads. The measured maximum horizontal displacements in walls with full-height panel facing and modular block facing were about 55% and 85% of those predicted from current design guidelines at EOS3, respectively. The influence of the surcharge loads on the reinforcement loads was found to be substantial for both wall types, especially for the case of model wall with modular block facing, where the reinforcement loads in the upper half of the wall increased by about 30% from EOS2 to EOS3. The insights garnered from this study contribute to a deeper and more nuanced understanding of the impact of facing types on the practical construction and design of MSE walls, offering valuable guidance for future engineering applications. • Two centrifuge model tests were conducted on walls with full-height panel facing and modular block facing. • The influence of the facing type on the performance of MSE walls was investigated. • The measured results were compared with those from current design guidelines. [ABSTRACT FROM AUTHOR]

A series of plate loading tests on clay has been conducted in the centrifuge. The aim of the tests is to create a data set, which is freely downloadable, to validate numerical tools that account for geometrical nonlinearities. The tests include two sources of geometrical non-linearities. The first source is the reducing clay layer thickness below the plate, which causes an increase in resistance. The second source is the backflow of the clay around the tip of the plate. The backflow has a reducing effect on the plate resistance. This paper outlines four tests: two involving a wide plate and two with a small plate. Each plate geometry is investigated under both smooth and rough side model boundaries. An material point method (MPM) schematization is used for numerical analysis. The schematization and parameter selection are initially validated by comparing the MPM results against CPTu data in each test. The numerical analysis examines the impact of a finite layer thickness by analyzing various layer thicknesses. Furthermore, the analysis shows the influence of the backflow on the plate resistance by analyzing different ratios of shaft to plate width. In this study, the pore pressures below the plate and vertical and horizontal displacement fields are considered in addition to the load displacement curves. The MPM simulations are in good agreement with the centrifuge data. [ABSTRACT FROM AUTHOR]

Green and economical synthetic approaches for metal–organic frameworks (MOFs) and incorporating multiple functionalities into MOF matrixes are of great interest for wide applications. Herein, we developed a rapid, high-throughput and universal centrifuge tube grinding (CTG) synthetic strategy for the synthesis of a series of popular MOFs in centrifuge tubes. Significantly, a variety of catalytic and optically active organic, biological and complex molecules were incorporated into the in situ formed defects of MOF skeletons by one-pot CTG synthesis to achieve various novel MOF-encapsulated composite materials. Types of MOFs as well as different composites can be rapidly and greenly synthesized simultaneously in centrifuge tubes with different sizes on a single vortex mixer even on a gram scale. Our strategy provides a facile route for the incorporation of multiple functionalities, especially large active molecules, into MOFs and for greenly affording various MOF-based materials towards various applications in diverse areas. [ABSTRACT FROM AUTHOR]

Large-scale high-speed granular avalanches can be catastrophic; however, small-scale model tests cannot reproduce the high-speed impact effect, resulting in barrier designs lacking detailed knowledge considering the prototypical dynamic conditions of granular avalanches (e.g., high moving velocities and varied material volumes). In this paper, a well-designed centrifuge model is adopted to reproduce high-speed granular avalanches with variable flow velocities and material volumes, and a calibrated DEM model is also used to offer further insights. The results indicate that under high-speed impact conditions, the effect of granular volume on the pressure distribution pattern dominates, but its influence on the impact loading rate is less obvious. To estimate the high-speed impact force, a constant pressure coefficient of 1 can provide a reasonable estimation for the dynamic component if boulder impacts are excluded, and the static component can be calculated using the weight of the dead zone based on the assumption of a static state of the dead zone. In addition, considering the transition of the impact pressure distribution model caused by different granular volumes and flow velocities, a rectangular pressure profile is suggested for barrier design against high-speed dry granular avalanches when the peak total impact force is adopted as the design load. [ABSTRACT FROM AUTHOR]

This work investigates the feasibility of using a decanter centrifuge to separate solid particles coated with a high melting fat from a liquid oil. The process involves feeding cold silica particles into a melt, upon which the hardstock fat crystallizes, and the particles are subsequently separated using a decanter centrifuge. Being the first attempt for such a design, only the separation step is studied, and a model system is used. It comprised canola oil (CO), fully hydrogenated rapeseed oil a priori crystallized on silica gel particles. Different particle sizes and accelerations of gravity were studied. To measure the success of this separation process, the data from light microscopy, and differential scanning calorimetry of the feed, oleins, and stearins were used. The findings show that the separation of the fatty particles used in this work, and liquid oil in decanter centrifuges is feasible while future research should focus on the crystallization part of the process. The model developed to describe the oil‐holding capacity of the cake focuses on the capillary liquid entrapped in the spaces between the particles and sufficiently represents the experimental findings which show that separation efficiencies increase with increasing centrifugal acceleration. Practical Applications: This work introduces an alternative fat fractionation process by separating a model system of CO, FHRO, and solid entrainers through a decanter centrifuge. The results can be potentially used for the development of a fully continuous dry fractionation process, which can achieve in one step higher SE than the conventional ones and can be tripalmitate‐selective. [ABSTRACT FROM AUTHOR]

Solid–liquid separation plays a decisive role in various industrial applications particularly in the treatment and purification of suspensions. Solid bowl centrifuges, such as the decanter centrifuge, are commonly employed in these processes as they operate continuously and enable high throughputs with short processing times. However, predicting the separation performance of solid bowl centrifuges proves to be challenging due to dynamic phenomena within the apparatus, such as particle settling, sediment build-up, consolidation and sediment transport. In practice, design considerations and the dimensioning of the apparatus rely on analytical models and the manufacturer's expertise. Computational Fluid Dynamics (CFD) offers a way to deepen our understanding of these devices by allowing detailed examination of flow phenomena and their influence on the separation processes. This study utilizes the open-source software OpenFOAM to simulate multiphase flow in a laboratory-scale decanter centrifuge, solving individual transport equations for each particle size class. The basis is the characterization of the material through targeted laboratory experiments to derive material functions that describe the hindered settling and the sediment consolidation. Furthermore, experiments on a laboratory decanter served as validation. The results demonstrate the solver's capability to replicate clarification and classification within the apparatus. Furthermore, the solver supports the definition of geometries tailored to specific separation tasks. This research demonstrates the potential of CFD for a better understanding of complex centrifuge processes and for optimizing their design to improve performance. [ABSTRACT FROM AUTHOR]

Counterweight retaining walls (CRWs) are a variant of gravity-retaining walls that feature a pressure relief platform (RP) on the backfill side to reduce total earth pressure, offering a cost-effective option compared to traditional forms. However, the intricate interactions between CRWs and backfill, coupled with the lack of clear design guidelines, have restricted their use. This study examines the behavior of CRWs in translation mode using three different centrifuge model tests, each with varying fill heights. Observations show a slightly concave slip surface through the wall heel and a nearly planar slip surface extending from the edge of the RP to the back of the wall in an active limit state. Backfill movement can be classified into translation, sliding, and stable zones. Earth pressure distribution on the upper wall follows a trapezoidal pattern, whereas the pressure on the lower wall exhibits a triangular distribution. Earth pressure on the RP is approximately linear, peaking near the RP's edge. Introducing a friction angle mobilization factor for the potential first slip surface improves accuracy in calculating earth pressure. The tests were replicated to validate the analytical model for earth pressure calculations, using the adaptive finite-element limit analysis method. [ABSTRACT FROM AUTHOR]

Steel catenary risers (SCRs) provide a cost-effective solution for deepwater oil and gas production. However, SCRs are susceptible to potential fatigue failure due to the cyclic motions of floating platforms. Previous studies on the physical modelling of cyclic SCR–seabed interactions have primarily focused on either the continuous cyclic motion of an SCR or a single rest period between two SCR motion packets. However, our understanding of the development of seabed trenches and excess pore pressure and their effects on SCR fatigue during multiple episodes of SCR motion and soil reconsolidation remains limited. This study presents a newly developed model container capable of modelling three-dimensional SCR motions including heave, surge, sway, and vortex-induced vibration in a geotechnical centrifuge. A centrifuge test is conducted to investigate the vertical cyclic SCR–seabed interaction, considering five vertical cyclic motion packets with intervening periods of reconsolidation. The results indicate that ignoring the effects of reconsolidation leads to an overestimation of the fatigue life of an SCR. In this test, the SCR fatigue life is reduced by 18%–23% after five episodic SCR motion packets and intervening reconsolidation. [ABSTRACT FROM AUTHOR]

The µTAS/LOC, a highly integrated microsystem, consolidates multiple bioanalytical functions within a single chip, enhancing efficiency and precision in bioanalysis and biomedical operations. Microfluidic centrifugation, a key component of LOC devices, enables rapid capture and enrichment of tiny objects in samples, improving sensitivity and accuracy of detection and diagnosis. However, microfluidic systems face challenges due to viscosity dominance and difficulty in vortex formation. Acoustic-based centrifugation, particularly those using surface acoustic waves (SAWs), have shown promise in applications such as particle concentration, separation, and droplet mixing. However, challenges include accurate droplet placement, energy loss from off-axis positioning, and limited energy transfer from low-frequency SAW resonators, restricting centrifugal speed and sample volume. In this work, we introduce a novel ring array composed of eight Lamb wave resonators (LWRs), forming an Ultra-Fast Centrifuge Tunnel (UFCT) in a microfluidic system. The UFCT eliminates secondary vortices, concentrating energy in the main vortex and maximizing acoustic-to-streaming energy conversion. It enables ultra-fast centrifugation with a larger liquid capacity (50 μL), reduced power usage (50 mW) that is one order of magnitude smaller than existing devices, and greater linear speed (62 mm/s), surpassing the limitations of prior methods. We demonstrate successful high-fold enrichment of 2 μm and 10 μm particles and explore the UFCT's potential in tissue engineering by encapsulating cells in a hydrogel-based micro-organ with a ring structure, which is of great significance for building more complex manipulation platforms for particles and cells in a bio-compatible and contactless manner. [ABSTRACT FROM AUTHOR]

Loess area is the region that geohazards happened most frequently, accounting for 1/3 of the geohazards in China. Cutting slope has become the most prominent products in human engineering activities and slope failure induced by rainfall has become the main form in recent years. Well-instrumented centrifuge model tests have been introduced to investigate the failure process and failure pattern, including pore water pressure, progressive deformation-failure process and characteristic of the high cutting slope by rainfall. The results show that rainfall induced loess slope failure is characterized by shallow slide to flow and two deeper creepage sliding-tension surfaces. All the sliding faces are characterized by planar surfaces parallel to slope surface. The planar sliding surface differs a lot to the circular sliding surface in the gravitational soil landslide. The accumulative deformation especially the abrupt displacement before failure induced the excess pore water pressure, after which flow failure with high-speed happened. The pore-water transducers on both sides of the shallow sliding surface have distinct response to slope deformation. The quantitative monitoring data indicates that the liquefaction is not the reason but the result of the deformation accumulation and big transient deformation. [ABSTRACT FROM AUTHOR]

The water retention curve (WRC) of municipal solid waste (MSW) is the important hydraulic parameter for the study of unsaturated seepage analysis in landfills. Due to the compressibility and degradability of the waste, the search for a method to quickly and accurately test its water retention curve (WRC) is a current problem that needs to be solved. In this paper, considering the volume change of the waste specimens in test, the test principle of centrifuge testing of WRC is corrected to make it applicable to the testing of waste WRC. In addition, the WRCs of 20 MSW specimens with typical landfill compositions and porosities are measured using the corrected centrifuge test. The effects of compositions and porosities of waste specimens on WRC parameters were analyzed. The results are summarized as follows. Disregarding the height reduction of specimens resulted in overestimated matric suction values and underestimating volume water content values. By comparing uncorrected and corrected values, the maximum difference of the matric suction and volumetric water content reach 233 kPa and 11%, respectively. This study can provide a reference for accurately measuring the WRC of MSW using a centrifuge. For the waste specimen without kitchen and yard waste, composition had less of an effect on the WRC of waste compared to porosity. The effect of the content of the non-absorbable fraction on the residual volumetric water content θr and the parameter nv in the van Genuchten model was significant. The initial porosity n had a great effect on the parameter α. [ABSTRACT FROM AUTHOR]

Purpose: We evaluated the hypothesis that repetitive gravitoinertial stress would augment the arterial-pressure response to peripheral sympathetic stimulation. Methods: Before and after a 5-weeks G-training regimen conducted in a human-use centrifuge, twenty healthy men performed a hand cold-pressor test, and nine of them also a foot cold-pressor test (4 min; 4 °C water). Arterial pressures and total peripheral resistance were monitored. Results: The cold-induced elevation (P ≤ 0.002) in arterial pressures and total peripheral resistance did not vary between testing periods, either in the hand [mean arterial pressure: Before = + 16% vs. After = + 17% and total peripheral resistance: Before = + 13% vs. After = + 15%], or in the foot [mean arterial pressure: Before = + 19% vs. After = + 21% and total peripheral resistance: Before = + 16% vs. After = + 16%] cold-pressor tests (P > 0.05). Conclusion: Present results demonstrate that 5 weeks of prolonged iterative exposure to hypergravity does not alter the responsiveness of sympathetically mediated circulatory reflexes. [ABSTRACT FROM AUTHOR]

As a preventative measure to increase the stability of an anchored sheet pile quay in soft clay, deep cement mixing (DCM) column rows erected at the active side behind the quay wall were suggested in the current study. The effect of DCM columns rows on the responses of the quay wall and ground movements was examined using a three-dimensional finite element numerical model of back analysis based on a centrifuge model test. The mechanism of soil arching and the stress transfer from the yielding soil to the stabilizing columns have also been studied using numerical analyses. A parametric study was also conducted to assess the effectiveness of DCM column rows. Results show that the shielding effect of DCM column rows can effectively reduce the negative effects on the quay wall. The effect was brought about by the compression of the lateral soil between the columns caused by stress redistribution, along with the resistance of the column rows in the direction opposite to the soil movement. On the basis of this analysis, some preliminary conclusions can be drawn for the stability improvement of quay wall using DCM column rows in soft clay at the design stage. [ABSTRACT FROM AUTHOR]

Rice husk ash (RHA) is a commonly found pozzolanic material that has been used as a partial substitute for cement to reduce greenhouse gas emissions. Concrete-rice husk ash (C-RHA) piles can become an eco-friendly and cost-efficient slope reinforcement alternative. Therefore, a series of centrifuge modeling tests were conducted to understand the stabilities of precast and cast-on-site C-RHA pile-reinforced slopes when subjected to gravity loading. The results show that the precast construction method more substantially improves the slope stability immediately after construction because the precast pile strength peaks before the cast-on-site concrete is fully cured. Moreover, the cast-on-site C-RHA pile-reinforced slope is much more stable after the mixture is fully cured because the grout material creates better bonding between the pile and the surrounding soil as it seeps into the surrounding soil, improving the slope strength and stability. [ABSTRACT FROM AUTHOR]

The extreme drought–rainfall seesaw is projected to occur with an increasing frequency. However, there still lacks a thorough understanding of its impacts on slope behaviour, in which desiccation crack plays a key role. To address this issue, a centrifuge test was conducted to investigate the effects of drought-induced desiccation crack on slope instability under extreme rainfall. During the test, the non-cracked slope was firstly subjected to extreme rainfall with 100-year return period. Subsequently, a long-term drying was applied to induce desiccation crack, and hence forming a cracked slope. The cracked slope is then subjected to an identical extreme rainfall. The non-cracked slope only exhibits swelling deformation, whereas for the cracked slope, a slip surface (2 m in depth) is clearly observed to initiate from one deep crack at crest. The global sliding failure of the cracked slope is mainly related to preferential flow, which could result in soil shear strength reduction. [ABSTRACT FROM AUTHOR]

To address the issues of uneven sample lengths in the centrifuge machine bearings of the ternary precursor, inaccurate fault feature extraction, and insensitivity of important feature channels in rolling bearings, a rolling bearing fault diagnosis method based on adaptive sample length adjustment of one-dimensional convolutional neural network (1DCNN) and squeeze-and-excitation network (SeNet) is proposed. Firstly, by controlling the cumulative variance contribution rate in the principal component analysis algorithm, adaptive adjustment of sample length is achieved, reducing data with uneven sample lengths to the same dimensionality for various classes. Then, the 1DCNN extracts local features from bearing signals through one-dimensional convolution-pooling operations, while the SeNet network introduces a channel attention mechanism which can adaptively adjust the importance between different channels. Finally, the 1DCNN-SeNet model is compared with four classic models through experimental analysis on the CWRU bearing dataset. The experimental results indicate that the proposed method exhibits high diagnostic accuracy in rolling bearings, demonstrating good adaptability and generalization capabilities. [ABSTRACT FROM AUTHOR]

This study used centrifuge model tests to evaluate the dynamic behavior of piles and sloped ground. Two types of test models were created based on the ground's saturation. The researchers calculated p-y loops to analyze the dynamic interaction between piles and sloped ground, which can lead to liquefaction. In the dry sand model, the passive earth pressure of the slope greatly influenced pile behavior, while in the saturated sand model with liquefaction, the kinematic force of the slope had a significant effect. The study also derived a p-multiplier that can be applied to medium-dense soil based on the experimental results. [ABSTRACT FROM AUTHOR]

The use of the vertical centrifuge in the olive oil production process is generally assumed to be habitual and necessary for the elimination of both the vegetation water and the small olive pulp particles that are not eliminated during solid–liquid separation (horizontal centrifugation). Trials were carried out with different oil:water ratios to study the influence of this variable on both the quality parameters of the olive oils obtained and the loss of oil with the olive wastewater. The trials were carried out at the industrial mill level with oil:water ratios between 0.6 and 5.5. While no differences were observed in the quality parameters of the oils obtained, correct adjustment of the oil:water flow rates reduced the loss of phenols present in the oils by around 30%. In addition, the results show a direct relationship between the soluble effluent and the conductivity of the olive mill wastewater (alpechín) with the loss of oil in the effluent. This work proves that both oil quality and the competitiveness of the olive oil value chain can be increased with energy savings, water consumption reduction, and environmental sustainability. [ABSTRACT FROM AUTHOR]

The compatible deformation behavior of a clay core dam is an important safety-related factor; however, it has not attracted sufficient attention, especially when the zone layouts are different along the direction of the dam axis. In this study, three centrifuge modeling tests were performed to investigate this problem. Model MY1 includes only a homogeneous clay zone, MY2 includes inclined clay core and rockfill zones, and MY3 is a composite dam. MY3-D1 and MY3-D2 denote two dam blocks in MY3, and their dam types are identical to those of MY1 and MY2, respectively. The results show that the maximum settlements along the elevation occur at the half-way point of the height of the dam body during construction and are approximately 1% of the dam height. Nearly 90% or more of settlements occur primarily during the construction period. The postconstruction additional settlement difference between MY3-D1 and MY3-D2 is less than 2 cm; and the settlements induced by reservoir filling are very similar at 14.7 and 15.8% of the entire postconstruction settlement, respectively. This result indicates that the working characteristics of the composite dam are stable, and the compatible deformation of different zone layout sections of the dam is acceptable. [ABSTRACT FROM AUTHOR]

Excavation often results in a decrease in the stability level of natural and manmade slopes. To address this issue, a new reinforcement method––structuralized cementation––has recently been introduced to reinforce coarse-grained soil slopes. However, previous studies have not adequately considered the interaction between excavation and structuralized cementation. Consequently, in this study, a series of centrifuge model tests were conducted to investigate the deformation and failure characteristics of structuralized cemented slopes under excavation conditions. It was found that structuralized cemented slopes exhibit significant progressive failure from bottom to top when subjected to excavation. The depth of the slip surface and the safety limit of the structuralized cemented slope increases with an increase in the extent of the solidification zone. During the failure process, slope deformation occurs inside a limited region that expands toward the interior of the slope. Structuralized cementation induces a nonuniform distribution of displacement direction and increases the dilatancy extent of the potential slip surface. The failure mechanism of structuralized cemented slopes can be explained by the significant coupling processes of deformation localization and local failure, which may also elucidate the variation in the position and shape of the slip surface of the slope from using different cement contents. Structuralized cementation reinforces slopes by weakening and delaying the deformation localization of the slope under excavation conditions. [ABSTRACT FROM AUTHOR]

Permanent ground deformation due to fault rupture accompanied by an earthquake can be dangerous and result in considerable economic losses and human fatalities, as experienced during the 1959 Hebgen Lake earthquake in Montana and 1983 Borah Peak earthquake in Idaho, USA. Reducing the damage to the structure within the fault zone requires an understanding of fault-soil interactions through composite overburden strata. Here, a series of centrifuge modeling tests simulating normal fault rupture through different thickness ratios of composite overburden strata were conducted. The soft rock layer was simulated by cemented sand with a uniaxial compressive strength of 0.975 MPa. In all centrifuge modeling tests, a constant total model thickness of 100 mm was used. The normal fault simulation was started once the model was spun at 80 g, which correlates to 8 m of total soil thickness, and subjected to 4 m vertical offset along a normal fault dipping 60°. The results show that thickness ratio of the composite overburden strata affects the fault-affected zone properties and lengthens this zone up to a thickness ratio between soft rock and sandy soil of 70:30. [ABSTRACT FROM AUTHOR]

Numerous industries are concerned by the humanitarian, environmental, and economic consequences of debris flows, landslides, and material run-outs. However, the run-out behavior following a loss of confinement, e.g., dam failure, is not well understood. The material's complex constitutive behavior means multiple mechanisms contribute to the deformation, e.g., slope instability, seepage forces, erosion, or static liquefaction. In this study, centrifuge models of fly ash deposits, with varying initial deposit density and water table height, were subjected to a rapid loss of lateral confinement. Deformation, pore pressure, and water content measurements were used to investigate and separate the mechanisms governing the run-out. Static liquefaction was observed in deposits initially looser than the critical state and led to a rapid material outflow. Slope instability was the initial failure mechanism for denser deposits or those with reduced water tables, with transient stability due to dilation-induced negative excess pore pressures followed by progressive failures caused by seepage pressures from drainage and pore pressure dissipation. Cone penetration tests, performed before the loss of confinement at different penetration rates, were used to characterize the material run-out and volume change tendencies and demonstrate a practical tool for assessing the run-out risk of deposits in the field. [ABSTRACT FROM AUTHOR]

This study investigates the monotonic and cyclic performance of composite bucket foundation breakwater in clay through centrifuge modeling. The application of monotonic loads simulates extreme wave conditions, and cyclic load corresponds to long-term serviceability conditions. In centrifuge tests, three typical soil strengths were tested, and two load eccentricities were simulated to check the influence of wave force height. Multiple measurements were conducted, including rotation angle, horizontal displacement, vertical settlement, and pore pressure variation. When soil strength increases in monotonic centrifuge tests, the ultimate bearing capacity of the bucket foundation experiences significant growth, and the foundation failure pattern varies. In responding to the monotonic test, the foundation's rotation center constantly moved downward during the loading process, indicating that the deeper soil would be activated to resist the horizontal loading. In contrast, the rotation center movement in the symmetric centrifuge test was opposed to the non-symmetric test because the deeper soil was required to provide resistance to balance the more severe load under the non-symmetric loading condition. It should be noted that non-symmetric loading does not impact the bucket foundation as seriously as symmetric loading. The utilization of deep-soil resistance in non-symmetric tests is beneficial in controlling deformation. [ABSTRACT FROM AUTHOR]

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The paper considers features of purification the reprocessed uranium hexafluoride from 232, 234, 236U in two cascades of gas centrifuges with additional feeding streams of waste uranium hexafluoride to the product stages of the cascades. The effective purification from 236U in the first cascade is carried out at a 235U concentration of less than 20% in long cascades having a large number of stages. The parameters of the second cascade that significantly reduce the concentration of 232, 234U in the wastes were determined. As a result of the reduction with waste uranium hexafluoride, this stream ensures a commercial low-enriched product to meet the requirements of the ASTM C996-20 specification established for enriched industrial uranium hexafluoride. [ABSTRACT FROM AUTHOR]

This paper presents a new approach to analyzing the components of centrifuge rotor vibrograms using a 2D trajectory fractal analysis based on the Detrended Moving Average method. The method identifies the different noise oscillatory behavior of the rotor depending on the rotation frequencies, ranging from non-stationary unbounded and 1/f pink noise to correlated and uncorrelated noise. Fractal characteristics of the vibrograms were computed for the first time and demonstrated differences for rotation frequencies close to the eigenfrequencies and far from them. This paper also discusses the influence of gyroscopic effects on the natural frequencies of centrifuge oscillations and the excitation of second harmonics when the centrifuge rotates at higher frequencies. The main cause of rotor vibration is identified as the mass imbalance of the rotors, and this paper proposes a vibration classification according to source nodes to diagnose serviceable and faulty technical systems. Finally, the possibility of anisotropy of the vibrogram is discussed, and the oriented fractal scaling components analysis method is applied to pave the way for further investigation. [ABSTRACT FROM AUTHOR]

Decanter centrifuges are widely used in solid–liquid separation, and saving their energy consumption is very important. In this paper, a bend pipe installed at the end of the decanter centrifuge was designed to save energy, and the effect of different structural parameters of the energy‐saving bend pipes on the outlet velocity and the reaction torque was investigated. The results revealed that the outlet velocity and the reaction torque were reduced with the increase in the number of pipes, outlet area, and pipe length. Increasing the radial position had little effect on the outlet velocity, but increased the reaction torque. Decreasing the outlet area and increasing the radial position both weaken the separation performance of the decanter centrifuge. The best separation performance and reaction torque effect were achieved in a suitable structure. Furthermore, the turbulent intensity was reduced from 143% to 135% in the new machine installed with bend pipes. The energy‐saving efficiency dropped with the increase of the rotational speed and the value was 13.1% under 2500 rpm. The separation performance of the new machine was similar to that of the original machine, and the dewatering speed was increased with the increase of the axial position. [ABSTRACT FROM AUTHOR]

Fluid fine tailings (FFT) are a by-product of the process used to extract bitumen from surface-mined oil sands in Alberta, Canada. One of the FFT reclamation techniques involves mixing centrifuged FFT with coarse sand tailings to form non-segregating tailings (NST). While NST provides a means to achieve mine closure and reclamation objectives, the self-weight consolidation of NST takes years to complete in full-scale testing. This paper examines the use of bench-scale centrifugation for physical modelling of the consolidation of NST under centrifuge loading. A series of bench-scale centrifuge tests is conducted on NST specimens reconstituted at different sand–fines ratios (SFRs), along with conventional oedometer and standpipe tests. Micro-computed tomography technique with high resolution is used to quantify the internal structure of the centrifuged specimens, and to infer the segregation and consolidation behaviour of NST specimens under 1-g and centrifuge loading. No segregation is detected in NST specimens under 1-g loading, while segregation occurs in NST specimens with low SFRs under centrifugal loading. Thus, only consolidation behaviour of NST specimens without segregation is investigated and compared to those determined from conventional oedometer tests. Limitations on use of bench-scale centrifuge in physical modelling of consolidation behaviour of oil sands tailings are addressed. [ABSTRACT FROM AUTHOR]

A study aimed towards assessing the variation in shaft capacity of piled foundations in swelling clays is presented. At the clay's in-situ water content, the results of pull-out tests on short-length piles revealed no dependency of shaft capacity on overburden stress. Conversely, after achieving a targeted value of swell, a strong dependency on overburden stress was observed. In upper portions of the profile where swell can occur relatively freely, swell-induced softening results in a reduction in pile shaft capacity. However, at greater depths where swell is largely suppressed, so too are the effects of swell-induced softening. For this reason, shaft capacity at depth was found to remain relatively constant before and after swell. The results of an instrumented pile test revealed an overriding dependency of lateral induced swell pressure on the magnitude of heave which has occurred. Irrespective of the level of overburden stress, lateral pressures against the pile were found to increase at early stages of the swelling process, but then reduce as swell continued and softening began to occur. Such a result highlights the importance of carefully considering the level of swell at which shaft capacity should be assessed if a conservative design is to be obtained. [ABSTRACT FROM AUTHOR]

Solid–liquid separation is a fundamental operation in process engineering and thus an important part of many process chains in the preparation of slurries in the chemical industry and other parts of the industrial environment. For the separation of micron-sized particles which, due to their size, do not settle or settle very slowly in the earth's gravity field, centrifuges are often used. The preferred choice are often decanter centrifuges because they work continuously and stabilize the process against product fluctuations due to their adjustment possibilities. The design of the apparatus is complex: The main components of the apparatus are the cylindrical-conical bowl, which rotates at a high speed, and a screw located inside the bowl, which rotates in the same direction at a low differential speed to transport the separated solids out of the apparatus. Geometrical properties of the apparatus, as well as the adjustable operating parameters, such as rotational speed or differential speed, have a significant influence on the separation. In practice, analytical models and the experience of the manufacturers form the basis for the design. Characteristics of the disperse phase, interactions with the liquid, as well as the influence of the flow on the separation, are not taken into account. As a consequence, the transfer to industrial scale always requires a large number of pilot-scale experiments, which are time-consuming and expensive. Due to the increasing computational power, computational fluid dynamics (CFD) provides one possibility to minimize the experimental effort in centrifuge design. In this work, the open-source software OpenFOAM is used to simulate the multi-phase flow in a laboratory decanter centrifuge. For validation, experiments were carried out on a laboratory scale and the main operating parameters, such as speed, differential speed, and volume flow rate, were varied. The simulation results show a good agreement with the experimental data. Furthermore, the numerical investigations show the influence of the flow on the separation of the particles. To evaluate the transportability of a material, the transport efficiency was introduced as a dimensionless parameter. In addition, the simulation allows the consideration of the individual velocity components, making it possible to generate an impression of the complex three-dimensional flow in the apparatus for the first time. [ABSTRACT FROM AUTHOR]