Core Part Research Articles

Numerical study of indoor flow field and ventilation performance of the power room of a diesel locomotive under crosswind

Power room is the core part of the railway internal combustion locomotives, houses many high-power equipment within a limited space. The ventilation performance of a power room are the key factors that ensure the efficient operation of locomotives. Numerical simulations were conducted to study the indoor and outdoor flow fields of the power room, with focus primarily on the indoor flow field of the locomotive. The effects of locomotive and crosswind speeds on the ventilation performance and indoor flow field of a power room were studied. Furthermore, the effects of fan performance on the power room ventilation were compared and analyzed. The numerical methods used were verified using experimental data. Results showed that as locomotive speed increased, the power room ventilation performance decreased, while the airflow rate of certain power room air intakes increased, with an increase in locomotive speed. Crosswinds significantly increased the power room ventilation quantity, especially when the intakes faced the crosswind. When the crosswind speed surpassed a certain threshold, the intakes on the leeward side of the power room entered an air-leakage state. The indoor flow field distribution of the power room was unaffected by the fan performance. Though the effect of fan performance on the amount of airflow entering the power room varied, the fan performance positively correlated with the overall ventilation performance of the power room. Considering the strong airflow separation caused by the back-step corner of the driver cab, attention should be paid to the placement and intake position of the power room in the design stage.

Electronic-ferry in metal element migration promoting deep activation of NiFe based phosphide for high efficient and stable oxygen evolution reaction

The design principle of high-efficient water electrolysis catalysis in oxygen evolution reaction (OER) has been primarily focused on the construction of multi-metal active centres. However, the spatial barrier between nonadjacent metal sites restricts the electron transfer, thus limits the activation and stability of active sites for improving the OER performance. Herein, a concept of electronic-ferry strategy by metal element migration in OER reconstruction is adopted to form dynamic electron-bridge between heterogeneous metal ions, which synchronously improves the OER kinetics and the corrosion resistance of metals centres. By designing layered NiCrP@NiFeP with concentration gradient, Cr element stepwise-release from the core part endows electron-ferry along the path of Ni2+-Cr4+/Ni3+-Cr6+ and Cr3+-Fe4+, achieving deep activated Ni(Fe)OOH layer with highly stable Fe sites in OER reconstruction process. The reconstructed NiCrP@NiFeP electrode shows 270 mV overpotential at 100 mA cm−2 current density with steady working more than 2600 h.

A COMBINED MODEL OF THE DIAPIRIC AND COLLISIONAL FORMATION MECHANISM OF THE PALEOPROTEROZOIC GRANITE-MIGMATITE-GNEISS DOMES OF THE SVECOFENNIAN BELT

Geological examples of the development of thermal dome structures in the Svecofennian belt demonstrate the relationship between plutonic and metamorphic events and metamorphic strengthening towards the core parts of the structures. The corresponding 2D geological model has been created to make a quantitative assessment of the effect of mantle magmas temperature at the base of the crust and the formation of the diapiric cores surrounded by high-temperature areas with a degree of granulite facies metamorphism. Modeling shows that there is a possibility of melting of the lower crust in the presence of a water fluid under the influence of mantle magmas. After melting, there occurs an ascent of partially molten material towards the upper crustal levels. An absorbed aqueous fluid changes to hydrous melt, thus lowering its viscosity and density. The ascending height of high-temperature cores is determined by the depth of viscous-to-elastoplastic transition in the crustal matter rheology. These materials ascend to upper levels in a partially molten state in the process of overthrusting due to "collisional" tectonics.

Ethnographic closeness: methodological reflections on the interplay of engagement and detachment in immersive ethnographic research.

With the reflexive turn in the social sciences, emotional engagement is an inevitable and crucial part of data-gathering and analysis. However, there is a glaring gap in methodological discussions to this end. Presenting ethnographic research into end of life with people living at home in England with heart failure, we argue for a methodological blend of engagement and detachment that shifts throughout the research process, and that sensory experience is a core part of engagement. We offer ethnographic examples which present and explore some alternatives to emotional engagement and objective detachment: (1) moving with participants to facilitate engagement during fieldwork through shared sensory experience; (2) detachment as a different way of relating when exiting the field and drawing participant relationships to a close; and (3) ethnographic closeness as the interplay of engagement and detachment in participant debriefing and data analysis. Based on well-established anthropological concepts, and taking both engagement and detachment as embodied and relational, we develop a notion of ethnographic closeness in which detachment is a necessary part. Our detailed methodological discussion thus offers theoretically grounded possibilities and alternatives for approaching and managing the core tension of 'how close is too close?' in ethnographic practice. Further contributions supporting researchers in navigating ethnographic research are needed.

Erector Spinae Plane Block Performed in the Emergency Department for Abdominal Pain: A Case Series.

Ultrasound-guided nerve blocks are fast becoming a core part of opioid-sparing, multimodal, acute pain management in the emergency department (ED) setting. The ultrasound-guided erector spinae plane block (ESPB) has been shown to be effective in treating a variety of musculoskeletal and neuropathic painful conditions in the ED. Here we report the effective use of the ESPB for pain control in four patients who presented with acute abdominal pain related to biliary obstruction in a resource-limited setting. The ESPB may be helpful in treating abdominal pain related to biliary obstruction, which is a novel indication for this well-established technique. This application is particularly relevant in resource-limited settings with significant delay in definitive surgical management. Further research is needed prior to widespread adoption.

Evaluation of custom posts and cores fabricated by two digital technologies in core and post space dimensions.

To evaluate the adaptability between posts and post spaces and the rationality of cores fabricated by two digital custom post-and-core processes. Titanium post-and-cores were fabricated by digital scanning impression technology or digital scanning wax-pattern technology on tooth defect molds of incisors, premolars, and molars, with traditional lost-wax casts of these teeth as the controls. Micro-CT and a laboratory scanner were used to determine intervals between post wall and root canal wall of the root apex, middle, and cervix of each sample in cross-, sagittal, and coronal sections; intervals between the end of post and tooth; diameters of cervical, middle, and incisal part at cross-, sagittal, and coronal sections of each sample, as well as shoulder widths. The three fabrication processes showed significant differences in intervals between post-and-core prostheses and root canal walls, diameters of all parts of cores, and shoulder widths. Scanning impressions showed significant advantages in the main part of post-and-cores in incisors and premolars, while the scanning wax-pattern process showed obvious inferiorities in premolars and molars. As to core spatial size, values of measured sites in the scanning impression process were closer to the standard than those of the traditional process, while differences between the measured value of the scanning wax-pattern process were much more obvious than in the traditional process. The use of digital custom post-and-core scanning impressions improved the rationality and precision of post-and-core dimensions compared with two other processes.

Microstructure of TiAl Capsules Processed by Electron Beam Powder Bed Fusion Followed by Post-Hot Isostatic Pressing.

The microstructures of intermetallic γ-titanium aluminide (TiAl) alloys are subjected to a certain degree of Al evaporation when processed by electron beam powder bed fusion (EB-PBF). The magnitude of the Al-loss is mainly correlated with the process parameters, and highly energetic parameters produce significant Al evaporation. The Al-loss leads to different microstructures, including the formation of inhomogeneous banded structures, thus negatively affecting its mechanical performance. For this reason, the current work deals with creating EB-PBFed TiAl capsules with the inner part produced using only the pre-heating step and melting parameters with low energetic parameters applying high beam speed from 5000 to 3000 mm/s. This approach is investigated to reduce the Al-loss and microstructure inhomogeneity after hot isostatic pressing (HIP). The results showed that the HIP treatment effectively densified the capsules obtaining a relative density of around 100%. After HIP, the capsules produced with the inner part melted at 3000 mm/s presented a lower area shrinkage (around 6.6%) compared to the capsules produced using only the pre-heating step in the core part (around 20.7%). The different magnitudes of shrinkage derived from different levels of residual porosity consolidated during the HIP process. The HIPed capsules exhibited the presence of previous particle boundaries (PPBs), covered by α2 phases. Notably, applying low energetic parameters to melt the core partially eliminates the particles' surface, thus reducing the PPBs formation. In this case, the capsules melted with low energetic parameters (3000 mm/s) exhibited α2 concentration of 3.5% and an average size of 13 µm compared to the capsules produced with the pre-heating step in the inner part with an α2 around 5.7% and an average size around 23 µm. Moreover, the Al-loss of the capsules was drastically limited, as determined by X-ray fluorescence (XRF) analysis. More in detail, the capsules produced with the pre-heating step reported an atomic percentage of Al of 48.75, while using low energetic melting parameters led to 48.36. This result was interesting, considering that the massive samples produced with standard parameters (so more energetic ones) revealed atomic Al percentage from 48.04 to 47.70. Finally, the recycled small particles showed a higher fraction of α2 phases with respect to the coarse particles, as determined by X-ray diffraction (XRD).

Core–shell clustering approach for detection and analysis of coastal upwelling

A comprehensive approach is presented to analyze season’s coastal upwelling represented by weekly sea surface temperature (SST) image grids. The proposed model, core–shell clustering, assumes that the season’s upwelling can be divided into shorter periods of stability, time ranges, consisting of constant core and variable shell parts. A one-by-one core–shell clustering algorithm is provided. The algorithm parameters are automatically derived from the least-squares clustering criterion.The approach applies to SST gridded data for sixteen successive years (2004–2019) of coastal upwelling in the western Iberian coast, the northernmost branch of the Canary Current Upwelling System. Our results show that at each season, there are 3 to 5 time intervals, the ranges, at which the upwelling presents stable core patterns of relatively cold water surrounded by somewhat larger shell areas of warmer waters. Based on other experimental computations performed by our team, we conclude that this pattern is not just a purely local phenomenon but has a more global meaning. Inter-annual time series analysis are consistent among themselves and with existing expert domain knowledge.

Agata detector technology: recent progress and future developments

gamma -ray tracking is based on a new generation of position sensitive high-purity germanium (HPGe) detectors. A novel type of cluster detector was successfully developed and assembled for the high-resolution gamma -ray spectrometer Advanced Gamma Tracking Array AGATA. The core part of the detector consists of three encapsulated, 36-fold segmented HPGe detectors which are operated in a common cryostat. The Ge crystal is hermetically sealed inside an aluminium can. All energy channels provide best energy resolution of core and segment signals for an extended energy range well above 50 MeV. A low cross-talk level was determined for the HPGe detectors and its preamplifier circuitry. Related cross-talk corrections are essential for highest energy resolution and improved position dependent pulse shape information. Recently a new encapsulation technology was put into operation which is based on a renewable metal elastic seal. HPGe detector developments are concerned with technologies for the production of p+ and n+ contacts, the segmentation and passivation of encapsulated HPGe crystals. Semiconductor processing research specifically aimed to develop a stable, thin and easy to segment n+ contact. A novel process, based on pulsed laser melting PLM, was successfully employed to produce very thin n+ and p+ contacts preserving the Ge purity. The contacts were segmented using a photolithographic process and then the intrinsic surface between contacts was passivated to assure the electrical insulation between them. A small detector prototype with three segments was made using these new techniques and then successfully tested.

SARS-CoV-2 in digital era: Diagnostic techniques and importance of nucleic acid quantification with digital PCRs.

Studies related to clinical diagnosis and research of SARS-CoV-2 are important in the current pandemic era. Although molecular biology has emphasised the importance of qualitative analysis, quantitative analysis with nucleic acids in relation to SARS-CoV-2 needs to be clearly emphasised, which can provide perspective for viral dynamic studies of SARS-CoV-2. In this regard, the requirement and utilization of digital PCR in COVID-19 research has substantially increased during the pandemic, necessitating the aggregation of its cardinal applications and future scopes. Hence, this meta-review comprehensively addresses and emphasises the importance of nucleic acid quantification of SARS-CoV-2 RNA with digital PCR (dPCR). Various quantitative techniques of clinical significance like immunological, proteomic and nucleic acid-based diagnosis and quantification, have been comparatively discussed. Furthermore, the core part of the article focusses on the working principle and advantages of digital PCR, along with its applications in COVID-19 research. Several important applications like viral load quantitation, environmental surveillance and assay validation have been extensively investigated and discussed. Certain key future scopes of clinical importance, like mortality prediction, viral/variant-symbiosis, and antiviral studies were also identified, suggesting several possible digital PCR applications in COVID-19 research.

Progress Toward Medical Use of the Iseult Whole Body 11.7 T MRI: First Images

Neurospin is a neuroscience research center located in France at the Atomic Energy Commission (CEA Saclay). The facility is hosting an innovative whole-body 11.7 T MRI system that has delivered its first images in October 2021. The core part of the Iseult MRI is an actively shielded NbTi magnet cooled with a pressurized superfluid helium bath at 0.125 MPa and 1.8 K, providing a homogeneous magnetic field of 11.7 T within a 90 cm warm bore. After nearly twenty years of work and efforts, the magnet successfully reached its nominal field for the first time in July 2019. The field homogeneity has been adjusted and the control system tested against internal and external faults that could affect the future MRI operation. MRI peripheral equipment has been integrated and interactions between the gradient coils and the magnet and their impact on cryogenics and on the magnet safety system have also been studied. The MR scanner is now kept permanently at nominal field and the final calibration is on-going to prepare the first acquisition on a human volunteer. The paper will present the Iseult MRI commissioning status and the first images obtained, as well as a first feedback on the cryogenic plant operation after three years and a half at 1.8 K.

Short Distance Detection and Control System Based on Photoelectric Sensor and Its Application in Target Detection of Handling Robot

The photoelectric sensor is an electronic device that is widely used in industrial automation processes. The device uses light to detect whether an object exists. The photoelectric sensor detection control system is the core part of the photoelectric sensor. The system includes sensor processing chip, control circuit, detection optical structure and automatic teaching control algorithm. In this research, the core control chip of the automatic teaching system and the core part of the control circuit of the short-distance photoelectric sensor are set up. The modular circuit around the above chip is designed. The optical structure of the sensor is designed by Position sensitive sensor (PSD) photoelectric accessories and triangulation method. Meanwhile, the core circuit control chip (CSP) is applied to complete the basic functions of the short-distance photoelectric sensor. Among them, the optical structure is designed to collect and process the optical signal of the detected object. Based on this, the I/V conversion is needed after collecting the optical signal by PSD, and then the signal processing is carried out. The fuzzy PID control model is used to solve the problem that the control object cannot accurately establish the mathematical model. The designed photoelectric sensor is used for the handling robot, and the D-H mathematical model of the handling robot is established. The Robotics toolbox provided by MatLab is used to simulate the movement of the robot, and the sensor is used to detect the target of the robot grabbing. The experimental results show that the sensor uploads the coordinate information of the object to be grabbed to the software interface, and the handling robot can accurately grab the object with the help of the photoelectric sensor, and place it in the corresponding position according to the appearance color of different objects to be grabbed.

Steerable Simultaneous Multibeam Antenna Based on Reconfigurable Reflectarray

Multi-beam system is a core part for wireless concurrent communication and massive MIMO applications. Traditional concurrent communication techniques, like phased-array or digital beam-forming (DBF) system, suffer from massive RF frontends or power-hungry high speed ADCs, which makes them complex and expensive in fabrication. Inheriting the advantages of reflectarray and passive multi-beam system, we reported in this letter a novel and cost-effective concept of steerable simultaneous multi-beam antenna (SMBA). New features and the practicality of it are fully verified with theoretical analysis and experimental implementation of a prototype working at 7GHz with 300MHz bandwidth. With multiple beams steered simultaneously, the SMBA can eliminate the crossover regions between adjacent beams of passive multi-beam antenna. Experimental results indicate its potential in the design of diverse concurrent communication systems such as base stations and point-to-point links.

Recommendations for the holistic care of patients with hereditary ATTR amyloidosis: an international Delphi consensus of patient advocates and multidisciplinary healthcare professionals

Abstract Funding Acknowledgements Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Alnylam Pharmaceuticals Background Hereditary transthyretin-mediated amyloidosis (ATTRv) is a rare, progressive, and potentially life-limiting multisystem disease, with cardiac manifestations, managed in a specialist settings by a multidisciplinary team (MDT) and supported by allied healthcare professionals (HCPs). Purpose This online international Delphi survey aimed to evolve clinical-patient-led practical guidance for the delivery of patient-centred holistic care based on the needs and priorities of affected patients and their families. Methods A 14-member joint patient−HCP Primary Panel was convened including patient advocacy groups (PAGs) and key clinical specialties (neurology, cardiology, physiotherapy, psychology, nutrition and nursing). All members of the Primary Panel had a role in identifying the challenges and opportunities which could be addressed by the recommendations (Figure) and in the writing and reviewing of the recommendations, using published evidence/guidelines to support each recommendation. Guidance evolved on the care provision needed to support seven core goals: early diagnosis and treatment; disease monitoring and organisation of care; maintenance of physical rehabilitation and mental health; family-centred care and caregiver support; patient−doctor dialogue; access to social support; and social networking. Results Between June−October 2022, 100 HCPs and 22 PAG representatives from 27 countries took part in anonymised online Delphi voting to establish the level of agreement (≥75% group agreement) and feasibility in practice for 50 recommendations. The clinical–patient community endorsed all but one of the primary panel’s recommendations. However, only 34% (17 of 50) of the recommendations were identified by most HCPs as a core part of routine care at their institutions, with the remainder of the recommendations identified as either part of usual care (by <50% HCPs respondents) or as largely achievable (by a further 30%-45% of HCPs) with current resources. The highest level of agreement amongst PAG representatives was for the regular referral and assessment of patients by a nutritionist, patient education and information for families; the role of specialist centres in providing information on national patient associations; the option for interim review (telemedicine) between scheduled tertiary centre visits for patients with worsening of symptoms; the need for treatment decisions informed by discussion with the MDT and patients; and training of HCPs to increase disease awareness and early diagnosis/intervention. Conclusions This research highlights the challenges associated with the holistic care of patients, particularly in rare diseases, recognising the roles of PAGs and allied HCPs, including those in the cardiovascular specialty, in supporting patients and their families as part of a comprehensive care plan. Figure: Opportunities and challenges for the delivery of care for patients with ATTRv amyloidosis and their caregivers

From mud to limestone: Birth and growth of a giant reef in the Eifelian (Middle Devonian) of S Belgium

The Wancennes reef is a giant bioherm 3000 m-large and 300 m-high that developed during the early Eifelian partitus to costatus conodont zones. The basal banks are formed by an accumulation of crinoid debris stabilised by lamellar stromatoporoids forming a coverstone, with a typical pioneer fauna. A micritic core, mostly formed by coral bafflestone, forms the first relief of the reef and evolved laterally and upwards to coral-stromatoporoid bafflestone and framestone that form the bulk of the reef and corresponds to the diversification phase of building and non-building organisms. The reef-crest is dominated by massive stromatoporoids and subordinate tabulate corals whereas the back-reef accumulation of debris is very rich in organisms (climax phase). The development of the reef is strongly influenced by sea level variations. Two third-order eustatic sequences are recorded in the reef. The first one corresponds to the basal banks and micritic core (transgressive systems tract) and lower part of the skeletal framestone (highstand systems tract) ending with an emersion. The second sequence is recorded in the upper part of the framestone (transgressive systems tract) and reef-crest and associated facies (highstand systems tract). The final emersion of the reef marked its termination followed by the deposition of fine-grained siliciclastics. The bathymetry, light penetration and hydrodynamism are assessed by the facies and faunal associations. All point to shallow-water, high-energy environment at the base and top of the reef, with deeper and quieter conditions during the development of the micritic core.

Prediction of stress-fatigue life on the impeller of the reactor coolant pump based on fluid-thermal-structure interaction method

The reactor coolant pump (RCP) is the core part of the first loop in nuclear power plant. It plays a crucial role on the stability and security of the nuclear reactor operation. As the only rotating equipment in the RCP, the impeller needs to run tens of thousands of cycles in the high-temperature and high-pressure coolant, which significantly affects the physical properties and reduces the fatigue life. This paper mainly studies the law of the dynamic stress on impeller of the RCP based on the fluid-thermal-structure interaction method, further predicting the stress-fatigue life of the impeller based on the Palmgren-Miner theory. The results show that the impeller is subjected to periodic alternating stress during rotation. The stress value gradually increases with the increase of the flow. The location and value of the maximum stress on the impeller at each moment are inconsistent. The highest negative correlation between the stress amplitude and the fatigue life is found, and the correlation is more than 19%. Fatigue failure first occurs at the junction between the inlet edge of the blade and the hub, and the fatigue life on the impeller is calculated to be 146.6 years. The fatigue life of the impeller is greater than the designed life, thus characterizing the impeller safe for use in nuclear power plant.

Mapping Nanoscale Electrostatic Field Fluctuations around Graphene Dislocation Cores Using Four-Dimensional Scanning Transmission Electron Microscopy (4D-STEM).

Defects in crystalline lattices cause modulation of the atomic density, and this leads to variations in the associated electrostatics at the nanoscale. Mapping these spatially varying charge fluctuations using transmission electron microscopy has typically been challenging due to complicated contrast transfer inherent to conventional phase contrast imaging. To overcome this, we used four-dimensional scanning transmission electron microscopy (4D-STEM) to measure electrostatic fields near point dislocations in a monolayer. The asymmetry of the atomic density in a (1,0) edge dislocation core in graphene yields a local enhancement of the electric field in part of the dislocation core. Through experiment and simulation, the increased electric field magnitude is shown to arise from "long-range" interactions from beyond the nearest atomic neighbor. These results provide insights into the use of 4D-STEM to quantify electrostatics in thin materials and map out the lateral potential variations that are important for molecular and atomic bonding through Coulombic interactions.

The strange resilience of the UK e-Borders programme: Technology hype, failure and lock-in in border control

The UK government’s e-Borders project presents an intriguing anomaly: despite repeated and acknowledged failings of the project over two decades, it has remained a core part of border strategy across successive administrations. This article seeks to explain the surprising resilience of this programme by developing the concept of political lock-in. We combine insights from critical security studies with science and technology studies concepts of ‘tech hype’ and lock-in. We apply these insights to trace how e-Borders was constructed as a compelling technological solution to pressing security issues. This created a form of political lock-in, whereby the project became impossible to abandon because of its political urgency, despite increasing awareness of its unfeasibility. With the project caught in a liminal state of non-completion, successive governments expanded the scope of the programme by attaching new security problems to it, thereby rendering it even more unviable. Our analysis thus throws up a paradox: rather than mobilizing resources to accomplish its tech vision, securitization created forms of lock-in and paralysis that made the programme more difficult to accomplish.

Towards precise complex AM-FM signals decomposition under strong noise conditions: A novel two-level chirp mode decomposition approach

Many signals in the real world contain noise, which interferes with the analysis of signals. Under harsh environments, the signal will be seriously disturbed by strong noise and overwhelm its changing features. Decomposing the signal with strong noise can effectively reveal the actual change law of original signal. However, the current methods cannot effectively process complex amplitude modulation-frequency modulation (AM-FM) signals with strong noise, and suffer from serious mode aliasing problems. In order to effectively decompose complex AM-FM signals with strong noise, a novel two-level chirp mode decomposition (TCMD) approach is proposed in this paper. TCMD can effectively solve the mode aliasing problem caused by strong noise interference and accurately decompose each sub-signal from original signal with strong noise. TCMD mainly includes two core parts: instantaneous frequency (IF) extraction and signal decomposition. Firstly, we establish a new IF extraction model for strong noise signals called improved parameterized time–frequency transform (IPTFT), which overcomes the shortcomings of current PTFT that cannot effectively handle multi-component signals. IPTFT can effectively filter out the interference of strong noise and accurately extract the initial IFs of multi-component signal. Then, we propose a novel adaptive iterative envelope filter tracking (AIETF) for signal decomposition that adopts the adaptive decomposition idea. AIETF can effectively decompose complex multi-component signals with strong noise, accurately estimate the IFs and reconstruct sub-signals. Decomposition experiments of both simulated and experimental signals with strong noise were carried out to verify proposed TCMD. The results show that TCMD can effectively decompose strong noisy AM-FM signals with close IFs, fast-changing IFs and crossing IFs. Meanwhile, TCMD can also effectively decompose the vibration signals with strong noise of wind turbine gearboxes, aero-engine gearboxes, and faulty bearings under non-stationary conditions to obtain high-quality TFR. Furthermore, TCMD achieves better decomposition effect for strong noise signals than the existing decomposition and TFT methods.

Performance prediction of solid particle erosion in fluidic oscillators for fluidic hammers based on CFD-DPM

Fluidic oscillator (FO), the core part of fluidic hammer, is sensitive to erosion due to high flow velocity and slurry concentrations, limiting the service life and efficiency of the fluidic hammer. In the past, the erosion prediction of FO was independent of the impact body motion, which was quite different from the actual situation. Therefore, the erosion prediction of FO was carried out through CFD-DPM in this study considering the flow field coupled with the impact body motion. The results showed that the numerical predictions coincided with the experimental results qualitatively. Then, the effects of flow rate, particle concentration, particle size and flow properties of drilling fluids on the erosion of FO were predicted in turn through this method. Meanwhile, the erosion parameters of cumulative erosion, erosion asymmetry degree and erosion rate were interpreted and analyzed. According to the prediction results, some suggestions for drilling field operation were put forward.