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[Objectives] The elbow is a common component of ship piping system. Efforts have been made in order to predict the elbow erosion accurately.[Methods] In this paper,the numerical simulation is conducted to calculate and analyze the flow field inside the pipe. From the two aspects,i.e. the influence of the turbulence model on the prediction of the flow field in the elbow and the influence of turbulence model on elbow erosion calculation,intensive research into the method to predict the erosion of elbow by solid and liquid flows.[Results] The results show that the SST k-ω turbulence model,together with the Oka erosion model,can accurately predict the flow field distribution in the elbow. Turbulence model brings a significant impact on the abrasion calculation,where it affects the calculated value of final erosion and also makes a great difference in the distribution of predicted relative erosion.[Conclusions] The obtained results can provide guidance for future pipe erosion prediction.

Simple Summary: This study investigated the effects of plant growth promoting bacteria (Bacillus clausii) and Fe-modified biochar on soil fertility increases and mechanisms of carbon sequestration. Additionally, the impact on C-cycling-related enzyme activity and the bacterial community was also explored. The study results demonstrate that in comparison to the individual application of FeB and BC, the FeBBC treatment significantly relieves soil alkalization and enhances soil alkali-hydro nitrogen content and aggregate stability (particle size > 0.25 mm), thereby contributing to improved soil fertility and ecological function. Additionally, all biochar treatments exhibit higher soil organic carbon, thereby increasing organic carbon sequestration, particularly in the FeBBC treatment. Compared to a single ecological restoration method, FeBBC treatment can improve soil fertility and carbon sequestration, providing important reference values for urban green space soil ecological restoration projects. The soil of urban green spaces is severely degraded due to human activities during urbanization, and it is crucial to investigate effective measures that can restore the ecological functions of the soil. This study investigated the effects of plant growth promoting bacteria (Bacillus clausii) and Fe-modified biochar on soil fertility increases and mechanisms of carbon sequestration. Additionally, the effects on C-cycling-related enzyme activity and the bacterial community were also explored. Six treatments included no biochar or Bacillus clausii suspension added (CK), only Bacillus clausii suspension (BC), only biochar (B), only Fe-modified biochar (FeB), biochar combined with Bacillus clausii (BBC), and Fe-modified biochar combined with Bacillus clausii (FeBBC). Compared with other treatments, the FeBBC treatment significantly decreased soil pH, alleviated soil alkalization, and increased the alkali-hydro nitrogen content in the soil. Compared to the individual application of FeB and BC, the FeBBC treatment significantly improved aggregates' stability and positively improved soil fertility and ecological function. Additionally, compared to the individual application of FeB and BC, the soil organic carbon (SOC), particulate organic carbon (POC), and soil inorganic carbon (SIC) contents for the FeBBC-treated soil increased by 28.46~113.52%, 66.99~434.72%, and 7.34~10.04%, respectively. In the FeBBC treatment, FeB can improve soil physicochemical properties and provide bacterial attachment sites, increase the abundance and diversity of bacterial communities, and promote the uniform distribution of carbon-related bacteria in the soil. Compared to a single ecological restoration method, FeBBC treatment can improve soil fertility and carbon sequestration, providing important reference values for urban green space soil ecological restoration. [ABSTRACT FROM AUTHOR]