Erosion Rate Model Research Articles

Experimental study on predicting head-cut migration rate of check dams

Head-cut erosion is the primary mechanism causing overtopping-induced breaches of check dams. Furthermore, the dam fill soil properties directly influence the head-cut migration rate. Although the fill materials of most flume model tests are cohesive soils, there are no experimental studies on loess materials with low erosion resistance. Accordingly, this study conducted 26 groups of flume model tests on the check dam head-cut migration mechanisms. Furthermore, it comprehensively analyzed the factors influencing the characteristics of head-cut migration in check dams, namely compactness, water content, inflow, and head-cut height, from the macro-and micro-viewpoints. The head-cut erosion rate models of compacted loess were developed considering multiple factors. A nonlinear multiple head-cut migration coefficient regression model was developed using the energy dissipation theory, the findings from the head-cut erosion tests, and experimental results from other studies, while considering the water content, compactness, clay content, inflow, and head-cut height as inputs. Seven sets of measured data with different erosion resistances were selected to verify the rationality and accuracy of the proposed model. In general, the sensitivity analysis results showed that the model could be used for cohesive soil with strong erosion resistance and silty sand and loess with weak erosion resistance. Its generalization and prediction accuracy have been further improved compared to other models of the same type.

The effect of Diamond Like Carbon coating on the Solid Particles Erosion resistance of grade 410 stainless steel

Surface damage by solid particles impacting at high speed is a significant problem for many applications. Hardening and coating are widely adopted to improve surface resistance. The Diamond-Like Carbon (DLC) coating is produced by highly advanced methods that make it one of the hardest coatings with improved bonding to the substrate. In this study, the Solid Particles Erosion (SPE) resistance of the DLC coating deposited by Plasma Assisted Chemical Vapor Deposition (PACVD) on hardened stainless steel grade 410 (SS 410H) was investigated. The results were compared to the SS 410H and SS 410 without hardening. The ASTM G 76 gas blast tester was used to find the SPE resistance, represented by Erosion Rate (ER), under velocities of (30, 50, 70) meter per second and angles of (30, 45, 60, 70, 90) degrees. The results were used to provide the constants needed for a modified Sheldon-Kanher (SK) ER model to estimate the ER at any velocity and impact angle for the tested materials, most importantly, for the DLC coating. A ductile erosion behavior was observed for the tested materials where the ER is reduced by increasing the impact angle which proves that the DLC coating does not behave as a brittle material under SPE. The DLC coating showed the highest SPE resistance with improvement of 42–65% with almost no significant effect of the velocity and impact angle on the improvement rate. While the SS 410H showed an improvement of 6–44% with a significant fluctuation with the variation of velocities and angles. This study highlights the potential usage of DLC coating in mechanical parts exposed to solid particles, such as turbine/compressor blades.

Soil wind erosion rate on rough surfaces: A dynamical model derived from an invariant pattern of the shear-stress probability density function of the soil surface

Landscape types with sparse vegetation, gravel cover and ridge-like tillage measures are widely distributed in dryland, and they are the main areas of soil loss and dust emissions caused by soil wind erosion. The widespread land degradation caused by soil wind erosion in these areas is the main reason for the low quality of life of the local people. Therefore, soil wind erosion control has become an urgent task for governments. As is well known, understanding the dynamic process of soil wind erosion is the premise on which effective measures of soil wind erosion control are developed. However, the spatial heterogeneity of shear-stress generated by wind on the soil of rough surfaces and its driving mechanism on soil wind erosion have not been fully understood. Based on a series of wind tunnel experiments, the distribution of wind-caused shear-stress on the exposed soil surface (τs) of rough surfaces with plants, gravels, and ridges was calculated, and the probability density function of τs on these rough surfaces followed the pattern of the logistic function. The location parameter and scale parameter in the logistic function were correlated with the lateral coverage, ridge index and friction wind velocity on rough surfaces. Subsequently, a soil wind erosion rate model with the characteristics of an upscaling point-scale process was established. Tested by multi-source experimental data, the model has a satisfactory prediction ability. These findings greatly improved the understanding of the spatial heterogeneity of τs and the driving mechanism of τs in soil wind erosion, which will help establish a dynamic-based wind erosion rate model in the future.

Analytical and experimental analysis of indentation depth upon abrasive impact on metallic substrates

Abrasive blasting is a prerequisite to any thermal spraying processes to make the substrate rough. Assessment of indentation depth after abrasive impact is essential to analyze the produced roughness. However, no analytical model on indentation depth after abrasive blasting is available. Most of the available erosion rate models did not consider the elastic recovery of the elastic-plastic substrate materials. Furthermore, the reported models utilized substrate hardness as the influencing parameter without considering the strain hardening effect. Therefore, a novel indentation depth model was developed considering elastic recovery of the substrate and Johnson-Cook flow strength. Thereafter, the developed model was validated using the experimental results. This model was found to be in good agreement with the experimental data. The Johnson-Cook flow strength of the material was found to be a more influencing parameter as compared to the hardness in connection with material behavior during abrasive blasting.

Erosion wear behavior of NiCr+Cr3C2–NiCr coating under multi–impact angle and novel coating structure design

Despite advances in NiCr + Cr 3 C 2 –NiCr coating improving the erosion wear resistance at low impact angles, the deterioration at medium and high impact angles has not been solved for the impeller subjecting to multi–impact angle. Herein the conflict is circumvented by combining the erosion performance of the NiCr and Cr 3 C 2 –NiCr under different impact angles and proposing a novel coating structure. First, the NiCr + Cr 3 C 2 –NiCr coating specimens with different NiCr content were prepared using the plasma spraying system. Second, the erosion rate of NiCr + Cr 3 C 2 –NiCr coatings in relation to the impact angle and the concentration of NiCr was measured by an air jet erosion test system, the microhardness was measured on the polished cross-section, and the erosion morphology was observed by SEM and analysed. Erosion behavior analysis showed that the NiCr + Cr 3 C 2 –NiCr coatings exhibited the coupling erosion wear mechanism of high toughness and high hardness, where the dominant characteristic was depending on the concentration of NiCr. Then, a tangential functional gradient coating structure was proposed by combining the excellent erosion wear resistance of ductile and brittle materials at varying impact angles, and a semi-theoretical erosion rate model considering the influence of the NiCr concentration was established based on the deformation wear theory. The erosion rate model was validated by experiments which showed the error was within 9.15%. Consequently, the erosion rate can be regulated on demand along the entire eroded surface, which significantly improves the erosion resistance of cermet at medium and high impact angles, thus prolonging the residual life of remanufactured impeller.

An exploration on the machine learning approaches to determine the erosion rates for liquid hydrocarbon transmission pipelines towards safer and cleaner transportations

Erosion is commonly found in pipelines with existence of interactions between solid particles, fluid product transported and the surrounding materials. Erosion may lead to material degradation in pipeline and may eventually cause pipeline failure. This failure may cause catastrophic consequence to the surrounding health, property and the environment. Therefore, a better estimation on the pipeline erosion rate is critical for the pipeline engineers to maintain a safer, more cost-effective and sustainable operating condition. In this study, two erosion rate models were used to create an erosion rate database and three machine-learning approaches were developed to help pipeline engineers evaluate the optimal flow velocity. The major results of this study are threefold: First, a purely visual approach was used to present critical information to decision makers. Second, three machine learning approaches (classification tree, artificial neural network and Bayesian network) were established for the erosion rate determination. Third, the benefits and limits of each approach were discussed and evaluated. As novel methodologies to estimate pipeline erosion rate, the machine learning approaches can serve as simple or comprehensive tools to address the various pipeline operating scenarios, with certain or uncertain information. This study provides innovative, intuitive and cost-effective tools for the pipeline operators to predict the erosion rate under various operating conditions and handles the uncertainty via a probabilistic approach, aiming to build safer and more environmental-friendly pipelines.

Response of interrill erosion to flow parameters of sand loess in regions with high and coarse sediment yields

In the Loess Plateau, regions with high and coarse sediment yields are the main sources of the Yellow River sediments. The responses of the interrill erosion rate of the soil in this area (Shenmu soil) to flow intensity parameters were systematically investigated through indoor artificially simulated rainfall experiments considering five slope gradients (0.1564, 0.2079, 0.2588, 0.309, and 0.3584) and five rainfall intensities (60, 80, 100, 120 and 140 mm·h−1). Thereafter, an interrill erosion model was established based on two types of soil: Shenmu soil and Ansai soil. The experimental data of Ansai soil were obtained from a study by Wu et al. (2017). The results showed that for Shenmu soil, the interrill erosion mechanism can be classified into two types. The first type was detachment-limited interrill erosion in the initial rainfall phase and transport-limited interrill erosion in the subsequent rainfall. The other type was transport-limited interrill erosion during the entire rainfall duration. Among the flow intensity parameters (i.e., mean flow velocity (R2 = 0.92), shear stress (R2 = 0.84), stream power (R2 = 0.96), and unit stream power (R2 = 0.82)), stream power was found to be satisfactory for predicting the interrill erosion rate of Shenmu soil in terms of the coefficient of determination (R2). However, the interrill erosion rate model based on the stream power for the two types of soil exhibited low prediction accuracy. Furthermore, a general flow intensity parameter was derived to predict the interrill erosion rate of overland flow. Based on this parameter, an interrill erosion rate model for the two types of soil was formulated by multiple regression analysis with an R2 value of 0.96, a relative root mean square error of 18.9%, and a model efficiency of 0.94. Overall, this general flow intensity parameter was shown to be the preferred predictor for estimating the interrill erosion rate for steep slopes in the regions with high and coarse sediment yields.

A mechanical erosion model for two-phase mass flows

Erosion, entrainment and deposition are complex and dominant, but yet poorly understood, mechanical processes in geophysical mass flows. Here, we propose a novel and process-based two-phase erosion-deposition model capable of adequately describing these complex phenomena commonly observed in landslides, avalanches, debris flows and bedload transports. The model is based on the jump in the momentum flux including changes of material and flow properties along the flow-bed interface and enhances an existing general two-phase mass flow model (“Pudasaini S.P., 2012, A general two-phase debris flow model, Journal of Geophysical Research, 117, F03010, doi:10.1029/2011JF002186”). A two-phase variably saturated erodible basal morphology is introduced which allows for the evolution of erosion-deposition-depths, incorporating the inherent physical process including momentum and rheological changes of the flowing mixture. By rigorous derivation, we show that appropriate incorporation of the mass and momentum productions or losses in conservative model formulation is essential for the physically correct and mathematically consistent description of erosion-entrainment-deposition processes. We show that mechanically deposition is the reversed process of erosion. We derive mechanically consistent closures for coefficients emerging in the erosion-rate models. We prove that effectively reduced friction in erosion is equivalent to the momentum production. With this, we solve the long standing dilemma of mass mobility, and show that erosion enhances the mass flow mobility. The novel enhanced real two-phase model reveals some major aspects of the mechanics associated with erosion, entrainment and deposition. The model appropriately captures the emergence and propagation of complex frontal surge dynamics associated with the frontal-drag with erosion.

Dam breach analysis for the Hongshiyan barrier lake

This paper presents a hyperbolic erosion rate model and a calculating circular slip surface method of lateral enlargement, and obtain a numerical analysis method of the relative stability dam-breach flood analysis. This paper develops a DB-IWHR procedure based on this principle, preparing a dam breach flood procedure is simple, easy to understand and use program in Excel 2010 spreadsheet. This improves this program, and writes a flood regulation calculation program, forming a complete program of dam breach flood and flood regulation. This paper calculates Hongshiyan barrier lake breach flood flow and the reservoirs downstream impacts.

Optimization CFD study of erosion in 3D elbow during transportation of crude oil contaminated with sand particles

The oil industry transport the crude oil, but with entrained solid particles. Throughout the production operations of the upstream petroleum, crude oil as well as sand particles corroded from the zones of the formation are regularly conveyed through pipes as a mixture up to the well heads and among well heads and flow stations. In this study, a three-dimensional CFD (Computational fluid dynamics) model has been developed that describes a turbulent transport of solid sand particles as well as crude oil through elbows to predict the erosions rates, where various physical aspects have been combined together including flow turbulence, particle tracking, and erosion simulation. The model has been used to investigate the different parameters that effect for crude oil and sand particles on the erosive wear rate on the pipe walls. Where, the parametric studied for crude oil are viscosity, density, velocity and temperature, also, the parametric studied for sand particles are parti-cles size, particles density and mass flow rate. Therefore, the investigation included evaluated the erosive wear rate on the pipe walls with different parametric studding by using numerical method with CFD technique. This model includes simulation of the three dimensional for turbulent flow, sand particle, and erosion rates modeling. Where, used three methods to evaluating the erosive wear rate on the pipe walls, The Finite Model, The Erosion Rate (E/CRC) Model and The Erosion rate (DNV) Model. Also, in this work can be prediction of the ero-sion position occur on the pipe wall with various parametric effect. Then, the results presented shown that the rate of erosion is increase with increasing the friction between the oil and pipe wall by variable the parametric of crude oil or sand particles. Also, the results are shown that the position of erosion variable dependent on the parametric of oil and sand. Finally, the work shown that the CFD technique is good tool can be used to evaluating the erosion rate and erosion position on pipe wall with various crude oil and sand particles parametric.

Numerical study on flow characteristics and impact erosion in ultrasonic assisted waterjet machining

A 3D numerical model was established to study the flow field characteristics and particle erosion in ultrasonic vibration-assisted abrasive waterjet machining by using computational fluid dynamics. The vibration of target is realized by using user-defined functions and dynamic meshing. The trajectories of abrasive particles dispersed in fluid flow are calculated by employing discrete phase model. The material removal on impacted surface was considered by an erosion rate model. The results indicated that the erosion rate at center area of impacted zone is lower than that at peripheral area, which is owing to the influence of stagnation zone. The variation of pressure value at the impacted surface is related to the vibrating movement of workpiece. Due to the weakening of stagnation effect, the pressure value decreases with a reduction of impact angle. Moreover, it was found that the erosion rate induced by particle impact on target surface is increased when vibration is applied. The influence of ultrasonic vibration on erosion rate is more significant at lower impact angle.

Relationships between physical‐geochemical soil properties and erodibility of streambanks among different physiographic provinces of Tennessee, USA

AbstractErosion of cohesive soils in fluvial environments is dependent on physical, geochemical and biological properties, which govern inter‐particle attraction forces and control detachment rates from stream beds and banks. Most erosion rate models are based on the excess shear stress equation where the soil erodibility coefficient (kd) is multiplied by the difference between the boundary hydraulic shear stress (τb) and the soil critical shear stress (τc). Both kd and τc are a function of soil properties and must be obtained through in situ field or laboratory testing. Many studies have generated predictive relationships for kd and τc derived from various soil properties. These studies typically were conducted in watersheds within a single physiographic region with a common surficial geology and/or investigated a limited number of soil properties, particularly geochemical properties. With widely reported differences in relationships between τc and soil properties, this study investigated differences in predictive relationships for τc among different physiographic provinces in Tennessee, USA. Erodibility parameters were determined in the field using a mini‐jet test device. Among these provinces, statistically four unique clusters were identified from a dataset of 128 observations and these data clusters were used to develop predictive models for τc to identify dominant properties governing erosion. In these clusters, 16 significant physical and geochemical soil properties were identified for τc prediction. Among these soil properties, water content and passing #200 sieve (percentage soil less than 75 μm) were the dominant controlling parameters to predict τc in addition to clay percentage (< 2 μm), bulk density, and soil pore water chemistry. This study suggests that unique relationships exist for physiographic provinces that are likely due to soil physical‐geochemical processes associated with surficial geology that determine minerology of the cohesive soil. Copyright © 2017 John Wiley & Sons, Ltd.

Dominant parameters affecting the reliability of TBCs on a gas turbine blade during erosion by a particle-laden hot gas stream

Thermal barrier coatings (TBCs) with high brittleness usually exhibit uncertain lifetime due to their scattered mechanical properties and severe service conditions. Here we establish a method of assessing the reliability and the dominant parameters affecting the reliability of TBCs deposited onto a turbine blade substrate during erosion by a hot gas stream. An erosion rate model is established to analyse the failure of TBCs induced by a single solid particle. The velocity, angle, and erosion location of foreign particles attacking the TBCs in a hot gas stream are calculated via numerical simulation, and the distribution of erosion rate is obtained according to the erosion rate model of a single particle. Additionally, reliability methods along with sensitivity analysis are used to quantitatively assess the reliability of TBCs. The results indicate that the most significant parameter affecting the reliability is the pressure at turbine outlet, followed by the coating thickness and the rotational speed of rotor, while both exhibit more obvious effect than the lamella thickness. Moreover, possible approaches to improve the reliability of TBCs are also proposed based on the modeling study.

Abrasive jet machining of glass: Experimental investigation with artificial neural network modelling and genetic algorithm optimisation

AbstractThe paper presents an experimental-based study of abrasive jet machining (AJM) considering the effect of changing process parameters. A series of drilling tests were carried out on glass workpieces using sand as the abrasive powder. The influence of each process parameter; applied air pressure, standoff distance, nozzle diameter, particle grain size and impact angle on the machining performance was determined in terms of the resultant material removal rate (MRR). The experimental results revealed that MRR was highly dependent on the kinetic energy of the abrasive particles, with the applied pressure the dominant parameter. The experimental results were compared with an erosion rate model previously published by Jafar et al. Though correct trends were predicted, there was a large discrepancy between model and measured values. An artificial neural network (ANN) was utilised to model the MRR more precisely, particularly to establish relationships between applied machining parameters and experimentall...

Gas-particle flows and erosion characteristic of large capacity dry top gas pressure recovery turbine

Based on the erosion rate model and the particle rebound model of blade material obtained through accelerated erosion test under high temperature, systematic numerical simulations of the complex gas-particle flows in inlet volute and cascade of a large capacity gas pressure recovery turbine are performed in this paper. The influence of inlet volute structure and cascade channel structure on the aerodynamic performance and erosion characteristics of turbine is first investigated. Results show that although mixing flows and vortex flows are formed in turbine intake volute, total pressure loss of volute is less than 0.7% because of low gas velocity. Erosion damage on the trailing edge of nozzles and rotating blades is mainly caused by high-speed cutting behavior of ash particles. The typical inlet volute structure results in an uneven erosion of first stage nozzles along circumferential direction. Nozzles located below the horizontal split are mainly eroded in blade root area, while erosion distribution of nozzles located above the horizontal split is irregular, and worse than the erosion degree of the lower half circle. Flow acceleration characteristics and cascade circumferential structure must be comprehensively considered so as to simultaneously improve the aerodynamic and anti-erosion performance of turbine.

Analysis of Prognosis of Lowland River Bed Erosion Based on Geotechnical Parameters

Abstract The river erosion is a complex process, the dynamics of which is very difficult to predict. Its intensity largely depends on hydraulic conditions of the river channel. However, it is also thought that natural resistance of the subsoil has a great influence on the scale of the erosion process. Predicting the effects of this process is extremely important in the case of constructing a piling structure (for example, artificial reservoirs). The partition of the river channel causes significant lowering of the river channel bed downstream the dam which threatens the stability of hydro technical and engineering (bridges) buildings. To stop this unwanted phenomenon, stabilizing thresholds are built. However, random location of thresholds significantly reduces their effectiveness. Therefore, taking under consideration natural geotechnical conditions of the subsoil appears to be extremely important. In the light of the current development of in-situ tests in geotechnics, an attempt to use results from these tests to predict the bed erosion rate was made. The analysis includes results from CPTU and DPL tests, which were carried out in the Warta River valley downstream the Jeziorsko reservoir. In the paper, the general diagrams for the procedure of obtaining and processing the data are shown. As a result, the author presents two multidimensional bed erosion rate models built based on hydraulic data and results from CPTU or DPL tests. These models allow taking more effective actions, leading to the neutralization of the effects of the intensive bed erosion process.

New features of solid particle erosion damage of control stage blades in supercritical steam turbine

Reducing solid particle erosion of blades is one of the most urgent problems for high-parameter steam turbine power generation technology. Based on the erosion rate model and particle rebound model of blade materials obtained through accelerated erosion test under high temperature, erosion characteristics of flaky particles in control stage of a typical supercritical steam turbine were systemically studied using three-dimensional numerical simulation method. The erosion mechanism of hard coatings on nozzle suction surface is first revealed, and erosion resistance of boride coating with large oxide particles is validated through high-temperature erosion test. Results show that serious erosion damage of boride coating on the latter half of nozzle suction surface is caused by the combined rebounded impingement of large particles between 1000 µm and 2000 µm after their initial impingement on the nozzle pressure surface and the leading edge of rotating blade. The average particle impingement velocity can reach up to 150–180 m/s, and the impingement angle is in the range of 18°–28°. High-temperature erosion test results show that boride coating will soon broken and fall off under the continuing impact of millimeter-sized particles, which confirms that hard coatings are difficult to resist the high-intensity impingement from these large particles. Therefore, separating particles before entering the nozzle chamber with the employment of an inertial separator should be the optimal choice for improving the erosion resistance of turbine. The results of this study enrich the types of blade erosion damage and provide a new idea for reducing erosion damage of control stage blades.

The influence of nozzle chamber structure and partial-arc admission on the erosion characteristics of solid particles in the control stage of a supercritical steam turbine

Reducing solid particle erosion of blades is one of the most urgent problems for supercritical steam turbine power generation technology. Based on the erosion rate models and the particle rebound models of blade materials obtained through accelerated erosion test under high temperature, systematic numerical simulations of the complex steam-particle flow in high pressure inlet flow channel and governing stage cascade of a supercritical steam turbine with four control valves was performed in this paper. The influence the typical nozzle chamber structure and partial-arc admission on the erosion characteristics of control stage blades was first investigated. Results show that erosion condition of nozzles in the same nozzle segment vary greatly along circumferential direction, while erosion damage to the leading edge of different circumferential rotating blades is uniform. Compared with four-valve opening condition, erosion weight-loss of the whole nozzle segment increases by 14% and 25% under three-valve opening condition and two-valve opening condition, respectively. Besides, under the partial-arc admission conditions, some large particles coming from the steam admission nozzle segment will collide back and forth between vanes and rotating blades in the downstream nozzle segment without steam admission, thus causing certain erosion to the trailing edge of nozzle suction side.

In situ measurement of sediment resuspension caused by propeller wash with an underwater particle image velocimetry and an acoustic doppler velocimeter

Flow induced by propellers of waterborne vessels can cause sediment resuspension in estuaries, bays and harbors, where sediments are usually contaminated. Bottom shear stress due to propeller wash is the key parameter that determines the initiation of sediment resuspension and the subsequent erosion. A novel self-contained underwater miniature particle image velocimetry (UWMPIV) system has been developed and deployed to study sediment resuspension under propeller wash in a US Navy harbor in San Diego, CA. Near bed profiles of mean velocity and Reynolds stresses were measured to evaluate the bottom shear stress, and to validate the shear stress measured with an acoustic Doppler velocimeter (ADV) that is simultaneously deployed with the PIV system. The critical shear stress was estimated by directly observing PIV images and identifying the moment when sediment resuspension started. PIV measurement became unfeasible as the propeller speed increased and the optical access was blocked by high level of suspended solids. However, the development of the bed erosion was able to be recorded in PIV images at several intervals when sediment concentration was relatively low and the sediment bed was visible. The observed time series of cumulative erosion depth agreed well with an erosion rate model that depends linearly on the bottom shear stress excess.

Study on Erosion Characteristics of Solid Particles in the First Reheat Stage Blades of a Supercritical Steam Turbine

Reducing solid particle erosion (SPE) of blades is one of the most urgent problems for supercritical steam turbine power generation technology. Based on the erosion rate models and the particle rebound models of blade materials obtained through the accelerated erosion test under high temperature, erosion characteristics of the first reheat stage blades in a supercritical steam turbine was simulated and analyzed by three-dimensional numerical simulation method in this paper. The influence of operating conditions, particle size distribution in the inlet of nozzle, and axial clearance between vanes and rotating blades on the erosion distribution of cascade were explored quantitatively. Results show that the erosion damage of the first-reheat stage stator is mainly caused by suction surface impingement from oxide particles. In designed loading condition, small and medium size of particles mainly eroded the trailing edge (TE) of nozzle pressure surface, while large particles mainly impinge the leading edge (LE) of rotating blades and the TE of vane suction surface, and erosion increase along the blade height. When the turbine is running under part-load condition, particle impingement angle on stator pressure surface is basically unchanged, while impingement velocity slightly reduced. However, the amount of particles that impinge the stator TE suction side after their first-time impingement on rotor LE increase rapidly, leading to the more severe erosion damage of stator suction surface. The particle size distribution in the inlet of nozzle has a significant effect on the erosion simulation of first reheat stage blades, and the size distribution sampled in one unit may not be used to other units. When axial clearance changes, the erosion weight loss of vane pressure surface near TE is basically held constant, while the erosion weight loss in vane suction surface near TE decreases with the increase of axial clearance. For the supercritical 600 MW unit simulated in this article, the antiSPE performance and the unit efficiency can be balanced well when the axial clearance increases to 13 mm. The results in this paper will provide a technology basis for reducing oxide particle erosion in the first reheat stage blades of supercritical steam turbine.