Slurry Flow Research Articles

The Development of Empirical Correlations to Understand the Frictional Behavior of Aqueous Biomass Slurry Flows in Vertical Pipes

Highlights The frictional pressure drop correlation of agricultural residue-water slurry flows in vertical pipes is developed. Multiple linear regression with the backward elimination method was used in RStudio to obtain the optimal model. Some regression coefficients differ for different types of biomass feedstocks. The predicted pressure drops agree well with the experimental data within a 95% CI. Empirical models for the onset velocity of drag reduction of different particle sizes of biomass are proposed. Abstract. Large-scale biofuel production at levels equivalent to conventional oil refineries using long-distance pipeline hydro-transport of biomass can be a cleaner alternative to fossil fuels when it comes to economics and traffic congestion associated with the overland transportation of biomass. The transport of aqueous slurries of several saturated mass concentrations (5%-40%) and four particle sizes (from <3.2-19.2 mm) of two types of agricultural residue biomass (ARB) feedstock (corn stover and wheat straw) was studied through a vertical test section of a 29 m long, 50 mm diameter closed circuit pipeline facility, and frictional pressure drops were recorded at different flow rates (0.5-4.3 m s-1). A framework was developed in RStudio (4.0.5) to analyze the experimentally obtained frictional pressure drops of biomass slurries through a multiple linear regression approach using a backward elimination method and Akaike information criterion. An empirical model was proposed to predict slurry frictional pressure drop in terms of slurry velocity, slurry solid mass concentration, particle aspect ratio, and feedstock type. The model satisfactorily predicted the frictional pressure drops of both feedstocks of biomass-water slurry flows through pipes within a 95% confidence interval. The correlations introduced for onset velocities of drag reduction in terms of slurry solid mass concentrations seemed helpful to interpret the transition points of the corresponding slurries in vertical upward flows through pipes. The empirical correlation developed in this research could help select biomass slurry pumps and pipe dimensions when designing a typical long distance pipeline network for biofuel production at the commercial level. Keywords: Agricultural biomass wastes, Frictional loss prediction, Numerical model, Onset velocity correlation, Regression coefficients, Upward pipe flow.

Numerical Study on Flow-Melt Characteristics of Ice Slurry in Horizontal Straight Pipe with a Local Large Heat Flux Segment

Ice slurry is a high energy density coolant with excellent flow, phase change, and thermophysical properties. In order to investigate the recovery of ice slurry flowing through a local large heat flux segment, a 3D Eulerian-Eulerian model based on the granular kinetic theory considering the flow and melting phase change of ice slurry is developed. Sensitivity analysis of interphase forces is carried out. A comparison of the pressure drop, solid phase velocity, and heat transfer coefficient with empirical data is carried out, respectively. The calculated results are in good agreement with the experimental results, indicating that the numerical model could accurately describe the flow and melting characteristics. Thermophysical field distributions, the axial variation of ice volume fraction (IVF), recovery curve, the average heat transfer coefficient, as well as the re-uniformization length are obtained. After passing through local large heat flux segment, due to shear stress action, the IVF and the particle uniformity of the cross section have recovery characteristics. The gradient of the recovery curve decreases with increasing inlet IVF as well as with increasing Reynolds number. After the local large heat flux increases to a certain value, its effect on the recovery curve of the ice slurry is small. The re-uniformization length increases as the local large heat flux increases. The average heat transfer coefficient of local large heat flux segment increases due to damage of the boundary layer. These results can provide a theoretical basis for the design of ice slurry systems in practical application.

Research Progress on Numerical Simulation of Heterogeneous Flow Resistance in Sludge Conveying System

Sludge pipeline transportation is increasingly used in different fields. Flow resistance is an important influencing factor in the pipeline transportation of solid-liquid two-phase flow slurry, and studying its characteristics is of great significance for optimizing pipeline design, reducing pipeline erosion and wear, and reducing transportation energy consumption. In view of the complexity of sludge as the resistance characteristics of solid-liquid two-phase flow, it is often necessary to analyze the inline mechanism of solid-liquid two-phase flow in slurry with the help of high-precision turbulent flow model in computational fluid dynamics (CFD), which has become the research focus of heterogeneous solid-liquid two-phase flow pipeline transportation. This paper analyzes and summarizes the CFD simulation status of heterogeneous solid-liquid two-phase flow resistance in pipelines, points out the future research direction, and provides reference for the analysis of heterogeneous flow resistance of sludge pipeline transportation and the optimization design of conveying system.

Numerical investigation of Bi-model slurry transportation in a straight pipe

Slurry transportation through a pipeline system is a conventional mode of conveying solid material, which several industries have adopted across the globe. However, this mode of transportation is a complex phenomenon that requires high suspension stability of the particulates and high-energy requirements to deliver the solid materials continuously. Further, the researchers have adopted various techniques to make the continuous flow of solid materials through pipeline systems, such as additive addition and increasing the percentage of fine particles in the mixture. However, the accurate bi-model for the transportation of solid materials is not yet established. Therefore, in the present work, different mixture ratios (65:35, 75:25, 85:15 and 95:05) of silica sand and fly ash are considered to investigate the slurry flow characteristics. A numerical investigation is carried out for a bi-model slurry flow of silica sand (2650 kg/m3) and fly ash (2100 kg/m3) particulates having a mean diameter of 450 and 75 μm through a horizontal pipeline of 0.0549 m diameter. The accuracy of the numerical model and the procedure adopted for the current simulation is also validated by the available results in the literature. The work's outcomes reveal a significant drop in pressure with the increase in the percentage of fly ash in silica sand slurry. Further, the contours of the solid concentration, velocity distribution, granular pressure, granular temperature and wall shear stress are also envisaged and discussed in detail to analyze the effects of fly ash in silica sand slurry. Furthermore, Specific energy consumption is also calculated from the empirical relation for the different silica sand and fly ash ratios. The calculations show that the slurry mixture of 35% of fly ash in 65% of silica sand requires the least energy for transportation.

Arylene Diimide Derivatives as Anolyte Materials with Two-Electron Storage for Ultrastable Neutral Aqueous Organic Redox Flow Batteries

Arylene Diimide Derivatives as Anolyte Materials with Two-Electron Storage for Ultrastable Neutral Aqueous Organic Redox Flow Batteries

Isothermal calorimetry study of the effect of citric acid on the hydration kinetics of magnesium oxysulfate cement

The hydration kinetics of magnesium oxysulfate cement (MOS) with and without citric acid (CA) was evaluated via isothermal calorimetry. A series of tests were conducted with different MgSO4 solution-to-MgO ratios (r) and MgO with different activities at 15 °C and 25 °C. The test results indicated that the effect of CA on the overall cement hydration rate was determined by the CA dose (w) primarily and can be simulated by a generalized scale factor model. The heat flow and cumulative heat evolution of slurries with different CA dosages could be accurately predicted using the scale factor (f) model. There was a linear relationship between lgf and lg(w/w0), so the individual reaction order in CA could be obtained. The effect of temperature on the hydration kinetics of MOS cement with and without CA was modeled with the original scale factor model developed from the Arrhenius equation, and the apparent activation energy obtained was 66.3 and 74.9 kJ/mol, respectively. This study provided a basis for further in-depth research of the kinetic mechanism of the MOS hydration reaction.

Integrated characterization of wormhole growth and propagation dynamics in CHOPS reservoirs with a unified and consistent ensemble-based framework

In this paper, a unified and consistent ensemble-based framework has been established for the first time to simulate the wormhole growth and propagation dynamics in a cold heavy oil production with sand (CHOPS) reservoir. More specifically, a recently modified pressure-gradient-based (PGB) sand failure criterion has been integrated into a reservoir simulator via a damped-iterative-ensemble-Kalman-filter (damped-IEnKF) framework in which foamy oil mechanisms are considered to quantify the changes in porosity and permeability in a CHOPS reservoir conditioned to its oil, water, gas, and sand production profiles. Subsequently, such an integrated model was applied to a single-well case from the Cold Lake heavy oil deposit and then a five-well case from the Lloydminster heavy oil area by alternatively combining the skin factor concept to reduce the computational expenses without compromising the simulation accuracy. The composite impact of sand failure and slurry flow on the multiphase flow behaviour was examined with different sets of relative permeability curves at each distinct production stage. By conditioning the simulated model to the observed production in the five-well case, skin factors have been alternatively assigned to each well to quantify the near wellbore damage on the initiation and development of wormhole networks. Not only have the production profiles been well matched, but also satisfactory agreements between the simulation outcomes and the in-situ observations have been obtained for both cases. It is found that the saturations of residual oil and connate water can be both significantly reduced by the sand failure mechanism, while the overall relative permeability can be reduced by the presence of slurry flow. A high pressure difference in the vicinity of a wellbore was formed owing to a large skin factor with respect to the restricted wellbore flow rate, significantly aggravating the sand failure. To better reproduce the production profiles in the five-well case, different skin factors were used for each well. In practice, the wormhole growth and propagation dynamics can be accurately and efficiently evaluated and forecasted with such an integrated model in a CHOPS reservoir, demonstrating its practicality and reliability in simulating the wormhole network dynamics and evaluating the performance of subsequent enhanced oil recovery (EOR) processes within a unified, efficient, and consistent framework.

Bidirectional Coupling Analysis of Support Pipeline for Shock Damping of Dilute Debris Flow

With the frequent occurrence of geological disasters and extreme weather, pipeline failure accidents and secondary disasters caused by debris flow continue to occur. Aiming at the impact of thin debris flow on support pipeline, a multi-physical coupling model of debris flow and support pipeline with vibration reduction is established based on the expansion flow model. The expansive fluid model is used to simulate the stress of the support pipeline under the action of thin debris flow. The results show that the impact effect of thin debris flow slurry on the support pipeline is concentrated at the inlet surface of the pipeline and the support, and gradually decreases to both ends. As the velocity of debris flow slurry increases, the stress acting on the support pipeline also increases. When the flow field tends to be stable, the load acting on the support pipeline maintains a stable value. The leading effect of debris flow slurry is the most serious damage to the support pipeline. The research results have a certain reference value for the impact of dilute debris flow in support pipeline.

Modeling of dynamic bridging of solid particles in multiple propagating fractures

During multi-cluster fracturing, solid particles are widely used to alleviate the non-uniform fluid distribution and fracture growth. Even though diversion technology has been applied and proved effective in numerous field applications, many involved physical mechanisms, such as solid diverters transport, settling, bridging, and packing in multiple propagating fractures, remain unclear. In this work, a computational mechanics system is developed to interpret the coupling process of fluid flow, fracture propagation, and particle transport. The moving fracture front is located using the implicit level set algorithm (ILSA) and tip asymptotic solution. The diverter particle transport model can capture the settling, bridging, and packing of particles; thus the slurry flow in the fracture can transit from Poiseuille flow to Darcy flow naturally. Application of the developed system to simulate a single stage of three equally spaced clusters indicates that it is possible to create multiple fractures with uniform length using diversion technology, but their widths are non-uniform. Instead, they demonstrate pinched or ballooned shapes, because of the stress interference. An extensive parametric study is also performed to investigate how various parameters affect diversion efficiency.

Spatiotemporal characterization of wave-augmented varicose explosions

The onset of three-dimensional instabilities during “Wave-Augmented Varicose Explosions” (WAVE) liquid disintegration is characterized for an annular flow of a shear-thinning slurry that is fed into a central transonic steam flow. Droplet production inside the nozzle is enhanced by ligaments radially flicking up from the slurry wave into the steam flow with radial:axial velocity ratios exceeding 0.5. The wave also leaves residual ligaments in its wake, which facilitate further disintegration. After birth, a wave spends 80% of the wave cycle period building up to peak height at the nozzle exit. Two effervescent mechanisms are provided as 1) steam penetrates the rising wave and surface deformation allows steam fingers to force through, and 2) the wave collapses on itself, trapping steam. Baroclinic torque drives the development of Rayleigh-Taylor (RT) instabilities and reaches values on the order of 1×1013 1/s2. Both RT and Kelvin-Helmholtz instabilities are self-amplified in a viscosity-shear-temperature instability cycle because the slurry is non-Newtonian. Velocities inside the nozzle (wave formation region) are generally azimuthally similar (two-dimensional), but those outside the nozzle (radial bursting region) are azimuthally uncorrelated (three-dimensional). Inter-variable correlations show significant decoupling of quantities beyond the nozzle exit, and local strain rate fluctuations were found to correlate particularly well with bulk system pulsation. Although adaptive mesh refinement (AMR) can provide computationally efficient resolution of gas–liquid interfaces, this technique produced different results than an equivalent non-dynamic mesh when modeling WAVE. Gradients were particularly affected by AMR, and turbulent kinetic energy showed differences greater than 150% outside the nozzle.

Predicting pressure-drop for pseudo-homogeneous slurry flows using the mixture model at high solids concentrations

The main contribution of this paper is applying computational fluid dynamics (CFD) using the two-phase mixture model with algebraic slip, and turbulent dispersion to the slurry flow experiment of Kaushal et al. (2012). The results obtained were compared to the experimental results and numerical results reported by the same authors who used the mixture model as well as a more advanced Eulerian granular flow model. The authors reported that the mixture model predicted the pressure drops with very high errors, especially for the highest solids loading simulated with errors as high as 400% compared to their experimental data. They conclude that the mixture model cannot be used to predict the pressure drop of the slurry flow investigated at higher concentrations (30-50% solid fraction). In contrast to this, the pressure-drop predictions of the two-phase mixture model with algebraic slip and turbulent dispersion used in this study were in good agreement with the measured values. This calls the conclusion of Kaushal et al. (2012). to question, because they did not present any justification for 3-4 times higher pressure drop observed in their study using the mixture model in combination with the fact that no anomalies in particle concentration profiles were observed by them for the mixture model. A comparison between the two mixture models reveals that although they differ in some details, the basic structure of the models is the same. We conclude that the mixture model with algebraic slip, turbulent dispersion, and a suspension viscosity model can be used for pressure drop predictions for the slurry flow investigated even for high solids fraction. We also demonstrate that the laterally averaged solids concentration profiles are not predicted very accurately by the mixture model as well as the more complex granular model. The concentration profiles predicted by the mixture model is easily understood in contrast to the profiles predicted by the granular flow model. From an engineering viewpoint, preference should be given to a simpler model, as was used in this study which can predict pressure drop with similar accuracy compared to a more complex approach with a larger number of uncertainty parameters. Further research is necessary to correctly predict the solids concentration profile for slurry flow in pipelines.

Flow behavior of impounded fly ash slurries using flow test

Coal ash is one of the largest industrial waste products generated in the United States. Since 1967, several failures in ash impoundments have been reported, releasing millions of gallons of impounded fly ash slurry and resulting in loss of life and mass environmental destruction. Several studies have been carried out to understand the flow behavior of fly ash slurries. However, several questions remain unanswered regarding the flow behavior of fly ash slurries after containment loss. In this study, a new flow test, a miniature version of a cylindrical slump test, was developed to investigate flow behavior of six different fly ash slurries. The flow behavior of these slurries was evaluated based on the yield stress derived from the flow test results. The results showed that some fly ash slurries flowed at higher solids content (>60 %), while others flowed at lower solids content (<50 %) and stopped flowing at higher solid content. Furthermore, some slurries did not flow at all. It was found that the chemical compositions of fly ash, the state of hydration (hydrated or non-hydrated), original solids content when received, and initial solids content of fly ash slurries at the start of the flow test played a major role in the flow behavior of fly ash slurries. The interactions between these factors were complex, and it was difficult to identify the effect of a single factor. Most of the fly ash slurries showed shear flow, and some slurries at high solids content showed elongational flow. The fly ash slurries with shear flow had larger flow areas after containment loss. The addition of an anionic polyacrylamide significantly increased the yield stress by 2.8 – 3.5 times and decreased the flow of fly ash slurries.

Thermo-fluidic characteristics of ice slurry flows in U-bend pipes for cold thermal energy storage

Thermal energy storage plays an important role in improving the efficiency of refrigeration systems. Ice slurries have a high potential for thermal energy storage due to their high latent energy storage properties and almost uniform temperature field. Ice slurry flows in heat exchangers can assist in peak load conditions of refrigeration systems. In the present study, the thermo-hydraulic behavior of ice slurry in U-Bend pipes as a component of heat exchangers was investigated. Numerical simulations were perforfemd using multiphase two-fluid model. Kinetic theory of granular flows were used for modeling the viscosity of ice particles. The effect of geometry of U-Bend pipes on heat transfer rate, pressure drop and ice slurry phase change were investigated. Numerical results were in good agreement with the experimental data. The results showed that heat transfer coefficient and pressure drop increase with Reynolds number, ice volume fraction and ice particle diameter. Tripling the particle diameter leads to the Nusselt number increase by 76 %. It was also found that by reducing the radius ratio, the heat transfer coefficient and the average skin friction coefficient increase, but overally it improves the performance. With a 100 % increase in Reynolds number, the average Nusselt number increases by 80 %, and by decreasing the radius ratio to 50 %, the Nusselt number increases by <1 %.

Study of Construction Technology of Large Diameter and Ultradeep Cement Mixing Pile in Road Engineering

As the soft soil in the Pearl River Delta area is deep, 50 cm-diameter cement mixing pile composite foundation is often used for road engineering. A municipal road in the Hongwan District of Zhuhai adopted a mixing pile with a diameter of 80 cm and a length of 27 m, which brought great difficulty to the construction of the project. To ensure the engineering quality, the bit optimization scheme was adopted to improve the blades from the conventional two layer and four groups of blades to three layer and six groups of blades. The projection direction of each layer of blades was vertical, which could increase the mixing times and improve the mixing uniformity. At the same time, double-channel teeth were added to effectively increase the smoothness of slurry flow. The optimized nozzle is improved from a nozzle located at the bottom of the drill bit to the left and right sides of the bottom of the drill pipe to effectively relieve the blockage of the nozzle, silt backflow, and other problems. The grouting pressure is generally 0.4–0.6 MPa. After the optimization of the grout pressure, the upper limit of 0.6 MPa was used in the first stirring and spraying process, and 0.4 MPa was used in the second stirring and spraying process. The advantage is that in the first mixing, excess cement grout is ejected for mixing, and in the second mixing, the total grout dosage can be controlled by reducing the grouting pressure, which effectively improves the quality of pile body and controls the cost. To ensure uniform soil mixing, measures were taken to improve the drilling speed of the drill pipe, accelerate the speed when sinking, slow down the speed when lifting. Through the above measures, the strength of the mixing pile body was improved, and the integrity of the pile body was guaranteed. Pile integrity, effective pile diameter, pile length, and pile strength uniform accord with the design. The difficult problem of large diameter and deep cement mixing pile is solved, which provides a good reference value for similar engineering.

CFD Modeling for the Influence of Fly Ash Particle Size on the Different Properties of High Concentrated Slurry Transportation in Horizontal Pipe

The disposal of fly ash from thermal power plants is becoming a serious concern for environmental engineers. This article attempts to study the influence of particle size of the fly ash on the various properties of high concentrated slurry (50 - 70 % by weight) flow through a horizontal pipe with the help of a commercial CFD code ANSYS FLUENT. Modified Herschel-Bulkley model and SST k-ω turbulence model is used for computational analysis, and the computational outcomes are validated with the available literature. In the present study, the fly ash samples were procured from different coal-based thermal power plants. Various properties: physical and rheological are obtained experimentally. The specific gravity of particles and the static settling concentration (SSC) of the slurry increases with the decrease in the particle size. The rheological properties increase as the concentration increases, and the slurry behaves like a non-Newtonian fluid at a high concentration. In addition, the particle size and concentration intensively impact on the skin friction coefficient and velocity distribution. However, no significant impact on the velocity profile at 70 % concentration (by weight).&#x0D; HIGHLIGHTS&#x0D; &#x0D; The rheological properties increase as the concentration increases, and the slurry behaves like a non-Newtonian fluid at a high concentration&#x0D; CFD modelling of the slurry flow at high concentration with modified Herschel-Bulkley model and SST k-ω turbulence model&#x0D; The particle size and concentration intensively impact on the skin friction coefficient&#x0D; &#x0D; GRAPHICAL ABSTRACT

A new calculation method and model of hydrate slurry flow of the multiphase pipeline in deep water gas field

The transportation environment of multiphase pipelines in deepwater gas fields is likely to cause the problem of hydrate flow safety. Aiming at the gas-liquid-solid three-phase flow problem containing hydrate, a hydrate slurry flow model for a multiphase pipeline in a deep-water gas field was developed based on the two-fluid model coupled with the population balance equation, and a mesh was carried out for the axial distance of pipeline and size difference of hydrate particles to obtain a transient solution. The multiphase flow characteristics of the pipeline are simulated upon engineering scale, the transient flow characteristics of gas and liquid phases, the aggregation and fragmentation characteristics of hydrate particles, and the coupling interaction between them were studied, which lays the foundation for further research on the characteristics of hydrate particle deposition and blockage based on particle size distribution. This study provides support for the safety of hydrate flow in multiphase pipelines in deepwater gas fields.

Numerical Simulation of Boulder Fluid–Solid Coupling in Debris Flow: A Case Study in Zhouqu County, Gansu Province, China

Boulders mixed with debris flows roll downstream under interactions with debris flow slurry, which poses a great threat to the people, houses, bridges, and other infrastructure encountered during their movement. The catastrophic debris flow in Zhouqu County, which occurred on 7 August 2010, was used as an example to study the motion and accumulation characteristics of boulders in debris flows. In this study, a fluid–solid coupling model utilizing the general moving objects collision model and the renormalization group turbulent model was used in the FLOW-3D software, treating boulders with different shapes in the Zhouqu debris flow as rigid bodies and the debris flow as a viscous flow. Numerical simulation results show that this method can be used to determine the motion parameters of boulders submerged in debris flows at different times, such as the centroid velocity, angular velocity, kinetic energy, and motion coordinates. The research method employed herein can provide a reference for studying debris flow movement mechanisms, impact force calculations, and aid in designing engineering control structures.

Pre-concentration of quartz from sea sand through superconducting high gradient magnetic separation technology

ABSTRACT In this study, a superconducting high gradient magnetic separation (S-HGMS) technology was used to separate and extract quartz from sea sand. Under optimal conditions (i.e., a magnetic flow ratio of 0.085 T·s/m, slurry flow velocity of 400 ml/min, and pulp concentration of 40 g/L), the SiO2 grade increased from 79.45% of the raw material to 91.35% of quartz concentrate, and the removal rate of Al and Fe reached 91.97% and 82.10%, respectively. Weakly magnetic particles in sea sand were selectively transformed to tailings, and the pre-concentration of quartz was achieved under a high magnetic field intensity. The high magnetic field intensity and mineral magnetic differences were the critical factors influencing the magnetic separation of quartz from sea sand. The S-HGMS technology achieved effective pre-concentration of quartz from sea sand, reducing the handling capacity and providing a high-quality material for subsequent quartz refinement processes.

Application of Extended Set Pair Analysis on Wear Risk Evaluation of Backfill Pipeline

Filling slurry can inevitably cause irreversible wear to the pipeline, which represents great costs to mines. This study aims to propose an extended set pair analysis (SPA) for the wear risk evaluation of backfill pipeline. First, to fully describe the wear risk of backfill pipeline, an evaluation index system was established from the aspects of slurry characteristics, pipeline properties, and slurry flow state. Then, the experts grading method was modified with probabilistic linguistic term sets (PLTSs) to obtain subjective weights. Meanwhile, the criteria importance through intercriteria correlation (CRITIC) approach was used to calculate objective weights. By introducing a preference coefficient, they were integrated to determine the comprehensive weights. After that, the classical SPA was extended with membership functions and fuzzy entropy theory, so that the wear risk of backfill pipeline can be evaluated from the perspectives of both the risk level and complexity. Finally, the proposed methodology was applied to assess the wear risk in the Jinchuan nickel mine, Dahongshan copper mine, Hedong gold mine, and Xincheng gold mine. The reliability of evaluation results was further verified through sensitivity and comparative analyses. Results indicate that the proposed methodology is feasible for the wear risk evaluation of backfill pipeline, and can provide guidance on the wear risk management.

Surface Damage Analysis on the Application of Abrasion and Slurry Erosion in Targeted Steels Using an Erosion Test Rig

The research focuses on slurry abrasion and erosion of martensitic steels used in the mining and agricultural industries. A traditionally constructed slurry pot tester with corundum abrasives in slurry form was used for wear characterisation. Wear testing was performed on each specimen for 180 h. Every 20 h, pauses were taken to characterise the specimen size, weight, hardness, and surface roughness. The worn zone’s damage progression was studied using optical microscopy. As the test period rose, the mass loss due to the wear, which was governed by the impact angle of the slurry flow, followed a linear pattern. The impact of specimen orientation on the wear rate was more pronounced than that of abrasive flow velocity. High-speed video recordings highlighted the varied contact conditions that caused the wear mechanism to shift from abrasion to slurry erosion. Slurry abrasion was seen at the bottom of the specimen as a result of pure sliding conditions, while pitting was observed at the top of the specimen as a result of fatigue from particle impact. Studies of 3D surfaces demonstrated a decrease in wear rate while transitioning from the abraded zone, which witnessed polishing and minor hardness, to the pitting zone. The wear performance of the materials was rated, with tempered martensitic steel coming out on top.