Effects Of Erosion Research Articles

The effects of beverage erosion on enamel: evaluating surface characteristics and loss of calcium and phosphate ions

BackgroundThe erosive impacts of various beverages on dental enamel have been identified as a potential erosive threat to dental hard tissues. This in vitro study aimed to address this by utilizing a systematic approach and advanced analytical methods to study enamel erosion due to selected beverages in a simulated oral environment.MethodsForty-nine extracted sound second premolar teeth were collected, disinfected, and prepared. These teeth were randomly allocated into seven groups, each exposed to a different beverage: distilled water, mineral water, instant coffee, black tea, Pepsi-Cola, orange juice, and synthetic vinegar. The modified Nordini Artificial Model (mNAM) was used to simulate the oral cavity. The enamel surfaces were scanned using a Scanning Electron Microscope (SEM) and analyzed using Energy-Dispersive X-ray Spectroscopy (EDS). Surface hardness was measured using the Knoop Hardness Scale. Statistical analysis was conducted using the Wilcoxon signed-rank test, with a significance level set at p < 0.05.ResultsDistilled water and mineral water exhibited no significant changes in enamel surface or hardness. Coffee caused an 8–9% loss of calcium and phosphate, indicating potential erosion. Black tea showed signs of remineralization rather than demineralization. Pepsi-Cola and orange juice caused substantial erosion, with Pepsi-Cola resulting in a nearly 24% loss of calcium. Vinegar had a marked erosive effect, with a 17% loss of both calcium and phosphate. SEM images corroborated these findings, showing pronounced enamel prisms and increased visibility of minor cracks in post-treatment teeth. EDS analysis revealed significant changes in the elemental composition of the enamel.ConclusionsThis study categorised beverages based on their pH and fluoride content, revealing that drinks like Pepsi-Cola and orange juice are acidic but low in fluoride, whereas black tea, mineral water, and vinegar are acidic yet contain fluoride. The study suggests that the decrease in pH of acidic beverages may contribute to dental erosion, with fluoride as a mitigating factor. Among the various metrics assessed for evaluating dental erosion, hardness emerged as the most reliable quantitative parameter.

Quantitative evaluation on the cavitation damage energy of metals via multiscale approaches

In-situ experimental observation cannot be an effective method in the impact process of metal cavitation erosion, and the impact damage energy prediction theory has not been established based on a detailed mathematical and physical model. Research has shown that the metal material can be regarded as a sensor to reflect the impact parameters. Soft metal materials such as industrial pure copper with a single α-phase microstructure can be a suitable sensor to detect cavitation erosion effects, revealing the impact behaviors of the cavitation jet through the depth, width and spatial distribution of cavitation pits on the surface. In this scenario, volume loss of cavitation pits on a macro/mesoscale are obtained by three-dimensional surface measurement. A coupled fluid-solid simulation model calculating the impact damage energy on a macro/mesoscale is established based on the Smoothed Particle Hydrodynamics (SPH) and the Crystal Plasticity Finite Element Method (CPFEM). Python programming is used to set the trajectory of SPH particles to determine the macro cavitation flow field. IFEM methods were used to construct the prediction theory of cavitation impact energy in a relatively simple exponential equation, establishing the quantitative relationship between cavitation impact damage energy and measured volume of cavitation pits. Compared with conventional measurement and simulation, the present multiscale approaches are assumed as a further step advancement towards calculating the impact damage energy of cavitation water jet.

Responses of soil microbial biomass carbon and microbial entropy to soil properties in typical sloping croplands of China under erosion conditions

Soil microbial biomass carbon (MBC) and microbial entropy play a crucial role in the carbon cycle of terrestrial ecosystems, while their responses to soil properties in typical sloping croplands under the impact of soil erosion remain poorly understood due to the complexity of the soil erosion process. In this study, we selected typical sloping croplands with different erosion levels for the four severely eroded soil types (black, loess, purple, and red soil) in China to assess the key controls of MBC and microbial entropy under the influence of soil erosion. The results showed that soil erosion significantly reduced the MBC content but increased the microbial entropy of sloping croplands in black soil region (BS) (22 %, 43.6 %), purple soil region (PS) (25.5 %, 26.2 %) and red soil region (RS) (28.9 %, 21.9 %), but not in loess soil region (LS). The soil physicochemical properties had significantly positive and negative correlations on the MBC and microbial entropy, respectively. The MBC and microbial entropy of these sloping croplands had different dominant drivers under soil erosion. Overall, our results revealed that changes in MBC and microbial entropy directly depended on the fundamental properties of the soil and soil erosion could indirectly affect the MBC and microbial entropy by directly affecting the physicochemical properties of soil. Thus, the impact of soil erosion on sloping croplands and the associated responses following changes in MBC and microbial entropy provide fresh insights into predicting the effects of soil erosion on carbon stability.

Coal deformation characteristics during methane displacement by pulsed nitrogen injection: New method of using pulsed energy to improve coal permeability

The displacement of methane by injecting nitrogen is an effective method for improving extraction efficiency in low-permeability coal seams. By conducting the experiments on uniform/pulsed pressure nitrogen injection for methane displacement (UPNI-MD/PPNI-MD), the coal deformation characteristics are quantitatively characterized, and the coal deformation mechanism is discussed. The results show that the technology of methane displacement by PPNI-MD is more effective in enhancing the permeability of low-permeability coal seams. The pressure of nitrogen injection and the amount of methane/nitrogen adsorption are crucial factors affecting the coal deformation during the process of UPNI-MD/PPNI-MD. The erosive effect of methane adsorption on the mechanical properties of coal decreases, while the erosive effect of nitrogen adsorption on the mechanical properties of coal shows a “wave-like” variation in the case of PPNI-MD. The application of PPNI-MD technology can effectively decrease the coal expansion deformation while undergoing the methane displacement process. Nitrogen injection to displace methane breaks the system energy balance of coal, resulting in deformation. And the coal deformation during nitrogen injection for methane displacement depends on the energy carried by the injected nitrogen, the energy change during gas competitive adsorption and the heat exchange between nitrogen and coal. The effective stress of coal depends on the change in methane/nitrogen pressure. The mechanical properties of coal depend on the amount of methane/nitrogen adsorption and the pore pressure. High-energy nitrogen damage to coal during the process of PPNI-MD is manifested in coal deformation caused by methane/nitrogen pressure, coal deformation caused by methane/nitrogen adsorption, and damage to coal mechanical properties caused by methane/nitrogen adsorption.

Perceived effect of soil erosion on maize production in Imo State, Nigeria

Perceived effect of soil erosion on maize production in Imo State, Nigeria

Long-term evaluation of surface topographic and topsoil grain composition changes in an agricultural landscape

Understanding long-term changes in topography and topsoil grain composition is crucial for the management of agricultural landscapes, especially in areas prone to wind erosion. This study investigates long-term changes in topography and topsoil grain composition within an agricultural landscape in south-western Slovakia. To analyse topographic changes over time, we used high-precision positioning measurements and airborne laser scanning to create digital terrain models (DTM) for the years 2011, 2017 and 2020. To assess changes in soil grain composition, we performed grain size analyses on soil samples collected during three different periods: M1 (1961–1970), M2 (2009–2015) and M3 (2015–2016). Changes in soil texture were evaluated to understand the impact of wind erosion on soil composition. The influence of windbreaks was also analysed by comparing the accumulation and deflation processes. The results showed significant changes in both topography and soil texture over the study period. The DTMs showed marked differences in the accumulation and deflation processes, highlighting areas affected by wind erosion. Comparisons of soil samples showed a shift in dominant soil types from loam and clay loam to silty loam, highlighting the effects of wind erosion. Analysis revealed a decrease in clay and silt content and an increase in sand content, indicating wind-induced soil degradation. The presence of windbreaks played a crucial role in reducing soil erosion by reducing wind speed, promoting soil accumulation and stabilising the landscape up to 80 m windward and 20 m leeward. The study highlights the complex interplay of climate and wind factors in shaping topography and soil properties and emphasises the protective role of windbreaks in agricultural landscapes over time. Our results show that wind erosion significantly alters soil texture, which can affect agricultural productivity. However, windbreaks have proven to be an effective measure in reducing soil erosion and maintaining soil quality.

Erosion-corrosion failure of overhead air cooler in atmospheric tower

ABSTRACT During the hydrogenation process in a petrochemical plant, the air cooler serves as a crucial heat exchanger in atmospheric towers. However, the frequent corrosion and leaks of air coolers significantly impact the safety of the process. Firstly, the Aspen software is utilized to simulate the operation of an air cooler. Then, Computational Fluid Dynamics (CFD) calculations are performed to analyze the internal flow in the air cooler. Finally, four inlet optimization strategies are proposed. It is indicated that the condensation of the oil phase results in the formation of liquid-phase oil droplets that cause erosion-corrosion. The absence of liquid-phase water condensation implies that there is minimal dew point corrosion in the tube bundle. The turbulence kinetic energy near the entrance exhibits significant variation, making erosion-corrosion more likely to occur near the entrance of the cooling tube bundle. Furthermore, vortexes form near the entrances of the first and second rows, exacerbating the corrosion in the tube bundle. By optimizing the air cooler, numerical simulations showed that the shear force of the vortex on the tube wall is reduced by nearly 50%. The internal erosion and scour effect of the improved air cooler is reduced.

Effects of cavitation and erosion on submersible drainage pumps: A numerical study

Submersible drainage pumps are used around the world both residentially and industrially for draining water and sewage. However, these pumps are prone to wear and clogging when the flows inward contain particles and air bubbles, and the combined effects of cavitation and erosion directly affect the performance of such pumps and degrade their efficiency. Therefore, it is essential to design a submersible pump that mitigates the adverse effects of cavitation and erosion. Reported here is an energy-efficient submersible drainage pump for use in emergency response. The combined cavitation–erosion effects are established in order to reduce their adverse impact on the pump, and how erosion wear affects the cavitation characteristics of the water in the pump is investigated. An experiment was conducted to verify the numerical results pump, and then, the influences of particle concentration and size on two-stage existing and altered model submersible pumps were analyzed using computational fluid dynamics. The results show that the performance of the altered model pump increased by 4.34%, with the cavitation–erosion effects reduced significantly. In addition, higher particle concentration induced higher erosion rates at both the leading and trailing edges of the impeller blades. Furthermore, the altered model significantly reduced the cavitation–erosion impact on the pump impeller blades compared to the existing model.

Designing sandwich-zigzag multilayered TiN coatings for corrosion-erosion coupling damage protection

Coatings are utilized to enhance the surface properties of materials. This study aimed to modify the TiN coating with a novel sandwich-zigzag intermediate layer and delve into the intricate damage mechanisms under harsh corrosion-erosion coupling environments. Due to the infiltration of NaCl into the coating and the subsequent formation of TiO2, the sandwich-zigzag TiN coatings exhibited a reduction in mechanical behavior and erosion resistance when exposed to salt spray at 550 °C for 50 h. Moreover, the erosion rates of the as-corroded TiN coatings displayed an opposite trend compared to that of the as-deposited coatings, showing that the erosion rate was highest at the erosion angle of 30°. Nevertheless, the presence of the zigzag-TiN intermediate layer benefited the coating by preventing stress accumulation and heterogeneous interface. This ultimately improved the erosion resistance of the coatings by more than 2 times at universal erosion angle compared to that of the substrates under the synergistic effects of corrosion and erosion.

Simulation of the effects of pile-rock breakwaters on the coastal sediment transport at Ganh-Hao beach, Bac-Lieu province, Vietnam

Abstract In recent years, the flat riverside coastal area of the Mekong Delta has been dealing with complex issues related to erosion and the buildup of sediment. Numerous research efforts have been undertaken to propose ways to address the adverse effects of shoreline erosion. One of these proposed solutions involves the construction of various types of breakwaters. A contemporary approach includes a design featuring concrete piles combined with a rock core, which has shown promising initial results in reducing wave impact and promoting sediment accumulation behind the structure. This study adopts a quantitative approach to examine how this structure influences sedimentation and erosion processes, the movement of suspended sandy sediments, and the seafloor within the zone extending from the structure to the shore. The research team utilized the Telemac numerical model, which combines dynamic hydrological calculations with simulations of coastal waves and sediment transport. The simulation results indicate a noticeable reduction in the concentration of suspended sandy sediments and an enhancement in sediment deposition in the area behind the coastal structure.

Soil erosion susceptibility prediction using ensemble hybrid models with multicriteria decision-making analysis: Case study of the Medjerda basin, northern Africa

Soil erosion is considered one of the most prevalent natural hazards in semiarid regions, leading to the instability of ecosystems and human life. The main purpose of this research was to investigate and analyze soil erosion susceptibility maps in the Medjerda basin in northern Africa. This study utilizes four ensemble models based on the analytical hierarchy process (AHP) multicriteria decision-making analysis, namely, deep learning neural network AHP (DLNN-AHP), frequency ratio AHP (FR-AHP), Monte Carlo AHP (MC-AHP), and fuzzy AHP (F-AHP). Eight predictor variables were considered as inputs to the model, namely, the slope degree, digital elevation model (DEM), topographic wetness index (TWI), distance to river (DFR), distance to road (DFRD), normalized difference vegetation index (NDVI), rainfall erosivity (R), factor and soil erodibility factor (K). Soil erosion inventory maps were developed from field surveys and satellite images. The dataset was randomly divided into 70% for training and 30% for testing. The performances of the utilized models were compared using a receiver operating characteristic (ROC) curve. The results highlighted that all the models utilized exhibited good performance, with DLNN-AHP (93.1%) exhibiting slight superiority, followed by FR-AHP (90.9%), F-AHP (88.9%), and MC-AHP (88.5%). Among the influencing factors, the distance to the river and rainfall erosivity had the most significant impacts on the incidence of soil erosion. Moreover, the current findings revealed that 38.3% of the study area is extremely highly susceptible to soil erosion. The results of this study can aid in developing decision-support tools for planners and managers aiming to mitigate the adverse effects of soil erosion.

Numerical Investigation of Effects of Ripple Type Needle Erosion on Pressure Inside a Pelton Nozzle

Abstract Pelton turbines, a commonly used impulse turbine for hydroelectric generation which converts the potential energy of the water into kinetic energy through a needle structure within the nozzle system. However, the exposure of the Pelton turbine components such as needle, seat ring, buckets to the sediment laden water can erode these components. The erosion on the needle can also lead to the efficiency degradation. This study aims to investigate the effect of needle erosion on the pressure dynamics within the Pelton nozzle system. For the study purpose, the nozzle system from Pelton rig at the Waterpower Laboratory, NTNU is used and a general erosion pattern is developed through literature and field information. The research focuses on analysing the difference in pressure distribution between the normal and eroded needles under different opening conditions, with the objective of understanding how erosion affects the nozzle performance. Single-phase 3-D simulations are performed with an unstructured ANSYS mesh and the CFX solver. This study examines the static pressure at the inner surface of the nozzle casing wall. The results show that for a constant head at the inlet boundary condition, the static pressure with eroded needles was significantly lower than that with normal needles. The pressure difference was around 1.88 kPa for a 60% nozzle opening and around 3.57 kPa for a 40% nozzle opening. The reduction in pressure is due to the increased area in the needle orifice and nozzle outlet caused by erosion, which is more pronounced at lower openings. The findings reveal a direct correlation between needle erosion and alterations in pressure distribution, highlighting the necessity for vigilant monitoring and timely maintenance. The study provides valuable insights into optimizing turbine performance in sediment-laden water conditions and underscores the importance of addressing needle erosion to maintain efficiency.

Synthesis and characterization of oleic acid-stabilized cobalt ferrite @MCM-41/nanocomposites for pH-responsive drug delivery

This study presents composite nanoparticles combining cobalt ferrites-oleic acid (CF-OA) and mesoporous silica (MCM-41) for drug delivery. Temperature-dependent analyses at 25 and 42 °C reveal distinct alterations in particle size and distribution, emphasizing the role of oleate complexes in stabilizing the nanocomposites. Power of Laws calculations (n = 0.58, m = 0.44) assessed diffusion and matrix erosion effects, highlighting the pH-responsive behavior. Results showed CF-OA@MCM-41with nanometric scale and predominantly spherical morphology influenced by temperature variations. Nitrogen BET analysis revealed a surface area of 542.1 m2g−1 and a pore volume of 1.1 cm3g−1. Drug release studies demonstrated controlled doxorubicin (DOX) release from CF-OA@MCM-41. In vivo studies showed significant tumor growth suppression (liver cancer): average tumor volume in D-C@M group was 167.8 mm3 after 21 days, compared to 1953.8 mm3, 1203.6 mm3, and 269 mm3 for PBS, CF-OA@MCM-41, and DOX alone respectively. In vitro, a 3 µg mL−1 concentration showed no significant 293 T cell viability change and increased HEP G2 cell viability. Significant HEP G2 cell viability inhibition occurred at 1 and 2 µg mL−1 CF-OA@MCM-41 carrying DOX, with p-values < 0.01 and < 0.001. CF-OA@MCM-41 nanoparticles exhibit promising potential for targeted cancer therapy due to their pH sensitivity and controlled drug release capabilities.

Assessment of fluvial response to landslide susceptibility and transient response of tectonically active upper Alaknanda River basin of Uttarakhand Himalaya, India

This paper focuses on the transient response of the upper Alaknanda River basin and landslide vulnerability analysis of tectonically active segments located between the Trans Himadri Fault (THF) and Main Central Thrust (MCT) in the higher central Himalayan domain. We applied the power law functions of the conventional bedrock incision proxies to decode erosionally balanced tectonic processes. The channel concavity and slope of the upper Alaknanda basin have been logarithmically evaluated to understand the balance between erosion/incision and tectonic events. Further, tectonically balanced erosional events along the trunk and tributary stream dynamics have been estimated using the Chi (χ) function law. The results of χ suggest a disequilibrium state of the trunk and tributary stream concerning steady state condition. Furthermore, the landform and longitudinal river profile have been analyzed to understand differential uplift/incision and impact of erosion in river profile between THF and MCT. Furthermore, we applied a geospatial technique for landslide susceptibility analysis. Our results show that approximately 94.45% of the basin area is highly vulnerable and has the potential for future landslides and glacial avalanches. Furthermore, we claim that this study is extremely helpful to identify the locations of future geohazards (landslide, avalanche, cloudburst etc.) and their impact on the downstream areas where population density is very high.

Submerged surface texturing of AISI 304L using the pulsating water jet method

Submerged jets have a variety of practical applications due to their versatility in providing efficient and environmentally friendly options for treatment in various industries. The physical background is based on the continuous water jet (CWJ) application powered via stagnation pressure. However, it is known that impact pressure is much more effective than static pressure. When the impact pressure is repeated with a high frequency per time unit, the erosive effects of water can be used even at pressures below 100 MPa, which is attractive from the point of view of the low demands of the hydraulic system. Surface modification utilising impact pressure can be achieved by employing the pulsed water jet (PWJ) method. The combination of parameters such as the traverse speed and trajectory pattern can control the number of water clusters impacting the material surface. So far, the field of application of PWJ for surface treatment has mostly been investigated water atmospheric conditions. This article focuses on the possibility of the surface modification of AISI 304L stainless steel using the PWJ method under submerged conditions. The results are compared to those obtained under atmospheric conditions. The reference samples were treated by the same technological conditions using a continuous water jet (CWJ). The affected surfaces were characterised using areal surface roughness parameters Sa, Sz, Sp, and Sv, and the surface topography and mechanism of erosion wear were evaluated by scanning electron microscopy. A significant increase in all roughness parameters was confirmed using the PWJ compared to the CWJ method (both in atmospheric and submerged conditions), which confirms the importance of using impact pressure. The surface treatment by PWJ under submerged conditions resulted in a decrease of the surface roughness parameter Sa by approximately 97% compared to atmospheric conditions at a traverse speed of 2 mm/s for perpendicular interleaved trajectory, nevertheless, the homogeneity of treatment over a larger area was improved.

Research on the erosion resistance characteristics of liquid-solid two-phase flow in high-pressure manifolds

During on-site throttling spray operations, the ground high-pressure manifold is subjected to the erosive effects of high-speed liquid-solid two-phase flow, which poses a high risk of erosive damage and eventual failure. In response to the erosive conditions caused by high-speed sand-carrying liquid-solid two-phase flow on the high-pressure manifold, an experimental apparatus for erosive testing was designed, taking into account key factors such as internal pressure loads. Microscopic erosive morphologies were observed in the experiments. Subsequently, numerical simulation methods were employed to investigate the identification of erosive danger zones and the influence of different installation angles, sand content, pipe flow velocities, and viscosity on erosive areas of the manifold.The research findings indicate that the microscopic morphological changes in erosive experiments align with the micro-cutting theory, which was successfully applied in simulation. Erosive danger zones are mainly distributed on the outer arch side, the curved arc connecting section, and the initial part of the outlet straight pipe. The erosive areas do not vary with changes in installation angles, sand content, and flow velocities. As viscosity increases, the erosive area shifts. The erosive rate is positively correlated with sand content and pipe flow velocity, and with increasing viscosity, the erosive rate on the first outer arch side shows an initial decrease followed by stabilization, while the second outer arch side exhibits an initial increase followed by stabilization. As the installation angle increases, the erosion rate on the second outer arch side first shows a stable trend and then decreases rapidly. At 75°, the erosion rate reaches the lowest.

Erosion Hazard Class Mapping in Dolago Das, South Parigi Sub-district

Introduction: Erosion can be caused by natural activities or human activities. Erosion events that occur naturally do not cause too many problems, but erosion events caused by humans can cause various problems of land damage or degradation and experience an accelerated rate of erosion. The Dolago watershed has an area of ±17,283.09 ha and is a priority watershed that needs attention because several natural disasters such as erosion, landslides, and floods have harmed the community when rainfall increases. Method: Based on the case above, researchers studied the erosion risk class of the Dolago watershed by combining erosion prediction methods, namely USLE and Geographic Information Systems. Erosion hazard class research was carried out in the Dolago watershed for 3 months, from September to November 2022 using the Universal Soil Loss Equation method and Geographic Information System, namely Overlay of several data (erosion determining parameters) to determine the erosion hazard class in the Dolago watershed. Results and Discussion: The results of research using the Geographic Information System and the Universal Soil Loss Equation method show that the amount of eroded soil in the Dolago watershed is 23,888.80 tons/ha/year and the erosion hazard class is divided into 5 classes, namely Class I (very light) erosion rate &lt;15 tons/ha/year with an area of 15,111.55 ha, class II (light) erosion rate 15 - 60 tons/ha/year with an area of 175.52 ha, class III (medium) erosion rate 61 - 180 tons/ha/year with an area of 1,244.87 ha, class IV (heavy) erosion rate 180 - 480 tonnes/ha/year with an area of 491.66 ha and class V (very heavy) erosion rate &gt;480 tonnes/ha/year with an area of 259.49 ha. Conclusion: Combining the geographic information system and the USLE method, five types of erosion hazard classes can be produced, namely class I classified as very light with an area of 15,111.55 ha percentage of 82.81%, class II classified as light with an area of 193.52 ha percentage of 1.12%, class III classified as moderate with an area of 1,815.52 ha percentage of 10.50%, class IV classified as heavy with an area of 682.32 ha percentage of 3.95% and class V classified as very heavy with an area of 279.56 ha percentage of 1.62%.

The Contradictory Issue of the Impact of Antecedent Soil Moisture to Interrill Erosion in Clay Soil: A Two-Year Field Study

The impact of antecedent soil moisture content on soil erosion has been a contradictory issue in erosion research, as well as process-based soil loss estimation models. The objective of this study was to investigate the impact of antecedent soil moisture content on the loss of clay soil through two-year runoff plot experiments under natural rainfall. Volumetric soil moisture sensors were used to monitor soil moisture changes, and readings were used along with rainfall records to quantify the antecedent soil moisture conditions. The results of this study show that the impact of antecedent soil moisture on interrill erosion is conditional, and the impact only exists in erosion events with a low Rainfall–Runoff Erosivity Index. The coefficient of determination between antecedent soil moisture content and soil loss per the Rainfall–Runoff Erosivity Index (Soil Loss/EI30) varies from 0.222 to 0.758, depending on the rainfall duration and Rainfall–Runoff Erosivity. The results of this study also suggest that accumulative rainfall within 48 h (Pp48) prior to an effective erosion event is strongly correlated with Soil Loss/EI30, particularly when the duration of an effective erosion event is either 3~7 h or 10~30 h. Hence, Pp48 can be considered as a replacement for antecedent soil moisture in process-based soil loss simulation models.

Analysis on cause of erosion of guide vane of high‐head Francis turbine in sandy river

AbstractThe Kizilsu River Basin in China is located in the desert Gobi area with high sediment content and high hardness. After 4798h operation, the maintenance of a high‐head Francis turbine in this basin found that the guide vane was seriously worn, and even most of the top and lower skirts of the front of the guide vane were worn off. In this study, the k‐ε turbulence model, ZGB cavitation model and sediment erosion prediction model were used to simulate the solid‐liquid two‐phase flow and cavitation of guide vane. The research results show that the guide vane of a high‐head Francis turbine in a sandy river has a high sediment velocity and serious surface erosion, with the maximum erosion rate of 1.0 × 10−6 kg/(m2·s), while the area near the skirt of the guide vane is a low‐pressure area lower than the saturated steam pressure, and cavitation is very easy to occur, with the maximum vapor volume fraction of 0.9. Serious cavitation erosion occurs near the skirt of the guide vane, and the combined effect of sand erosion and cavitation erosion on the surface of the skirt of the guide vane aggravates the damage of the skirt structure. The research results provide a technical basis for the antiabrasion design of the guide mechanism of the high‐head Francis turbine and the operation and maintenance of the hydropower station in the sandy river.

Well Integrity in Salt Cavern Hydrogen Storage

Underground hydrogen storage (UHS) in salt caverns is a sustainable energy solution to reduce global warming. Salt rocks provide an exceptional insulator to store natural hydrogen, as they have low porosity and permeability. Nevertheless, the salt creeping nature and hydrogen-induced impact on the operational infrastructure threaten the integrity of the injection/production wells. Furthermore, the scarcity of global UHS initiatives indicates that investigations on well integrity remain insufficient. This study strives to profoundly detect the research gap and imperative considerations for well integrity preservation in UHS projects. The research integrates the salt critical characteristics, the geomechanical and geochemical risks, and the necessary measurements to maintain well integrity. The casing mechanical failure was found as the most challenging threat. Furthermore, the corrosive and erosive effects of hydrogen atoms on cement and casing may critically put the well integrity at risk. The research also indicated that the simultaneous impact of temperature on the salt creep behavior and hydrogen-induced corrosion is an unexplored area that has scope for further research. This inclusive research is an up-to-date source for analysis of the previous advancements, current shortcomings, and future requirements to preserve well integrity in UHS initiatives implemented within salt caverns.