Lanxi Zhang¹, Yuming Peng¹, Yudong Wu^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.1, pp. 205-220, 2025, DOI:10.32604/fdmp.2024.056516 - 24 January 2025

Abstract The challenge of aerodynamic noise is a key obstacle in the advancement of low-pressure tube ultra-high-speed maglev transportation, demanding urgent resolution. This study utilizes a broadband noise source model to perform a quantitative analysis of the aerodynamic noise produced by ultra-high-speed maglev trains operating in low-pressure environments. Initially, an external flow field calculation model for the ultra-high-speed maglev train is presented. Subsequently, numerical simulations based on the broadband noise source model are used to examine the noise characteristics. The impact of the train speed and pressure level on noise generation is investigated accordingly. Subsequently, a… More >

Shande Li¹, Wen’an Zhong¹, Shaoxing Yu¹, Hao Wang^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.1, pp. 179-204, 2025, DOI:10.32604/fdmp.2024.056228 - 24 January 2025

Abstract This paper aims to numerically explore the characteristics of unsteady cavitating flow around a NACA0015 hydrofoil, with a focus on vorticity attributes. The simulation utilizes a homogeneous mixture model coupled with a filter-based density correction turbulence model and a modified Zwart cavitation model. The study investigates the dynamic cavitation features of the thermal fluid around the hydrofoil at various incoming flow velocities. It systematically elucidates the evolution of cavitation and vortex dynamics corresponding to each velocity condition. The results indicate that with increasing incoming flow velocity, distinct cavitation processes take place in the flow field. More >

Haoran Meng^1,2,3, Nianxun Li⁴, Xukui Shen², Hong Zhang², Tian Li^4,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.1, pp. 161-178, 2025, DOI:10.32604/fdmp.2024.055389 - 24 January 2025

Abstract The pressure wave generated by an urban-rail vehicle when passing through a tunnel affects the comfort of passengers and may even cause damage to the train and related tunnel structures. Therefore, controlling the train speed in the tunnel is extremely important. In this study, this problem is investigated numerically in the framework of the standard k-ε two-equation turbulence model. In particular, an eight-car urban rail train passing through a tunnel at different speeds (140, 160, 180 and 200 km/h) is considered. The results show that the maximum aerodynamic drag of the head and tail cars is More >

Jianing Hao¹, Dan Yang², Guanxiong Ren¹, Ying Zhao³, Rangling Cao^4,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.1, pp. 141-159, 2025, DOI:10.32604/fdmp.2024.054469 - 24 January 2025

Abstract This study presents an innovative approach to calculating the failure probability of slopes by incorporating fuzzy limit-state functions, a method that significantly enhances the accuracy and efficiency of slope stability analysis. Unlike traditional probabilistic techniques, this approach utilizes a least squares support vector machine (LSSVM) optimized with a grey wolf optimizer (GWO) and K-fold cross-validation (CV) to approximate the limit-state function, thus reducing computational complexity. The novelty of this work lies in its application to one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) slope models, demonstrating its versatility and high precision. The proposed method consistently achieves… More > Graphic Abstract

Haijie Zhang¹, Haifeng Zhao², Ming Jiang^3,*, Junwei Pu¹, Yuanping Luo¹, Weiming Chen¹, Tongtong Luo^1,4, Zhiqiang Li⁵, Xinan Yu⁶

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.1, pp. 221-232, 2025, DOI:10.32604/fdmp.2024.053496 - 24 January 2025

Abstract Pressure control in deep shale gas horizontal wells can reduce the stress sensitivity of hydraulic fractures and improve the estimated ultimate recovery (EUR). In this study, a hydraulic fracture stress sensitivity model is proposed to characterize the effect of pressure drop rate on fracture permeability. Furthermore, a production prediction model is introduced accounting for a non-uniform hydraulic fracture conductivity distribution. The results reveal that increasing the fracture conductivity leads to a rapid daily production increase in the early stages. However, above 0.50 D·cm, a further increase in the fracture conductivity has a limited effect on More >

Chakar Khadija^*, El Mouden Mahmoud, Hajjaji Abdelowahed

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.1, pp. 61-70, 2025, DOI:10.32604/fdmp.2024.053458 - 24 January 2025

Abstract The primary objective of this study is to develop an innovative theoretical model to accurately predict the thermophysical properties of hybrid nanofluids designed to enhance cooling in solar panel applications. This research lays the groundwork for our future studies, which will focus on photovoltaic thermal applications. These nanofluids consist of water and nanoparticles of alumina (Al₂O₃), titanium dioxide (TiO₂), and copper (Cu), exploring volumetric concentrations ranging from 0% to 4% for each type of nanoparticle, and up to 10% for total mixtures. The developed model accounts for complex interactions between the nanoparticles and the base fluid, More >

Ryan Randall¹, Chunmei Chen^1,*, Mesfin Belayneh Ageze^2,3, Muluken Temesgen Tigabu⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.12, pp. 2657-2691, 2024, DOI:10.32604/fdmp.2024.058169 - 23 December 2024

Abstract Vertical Axis Wind Turbines (VAWTs) offer several advantages over horizontal axis wind turbines (HAWTs), including quieter operation, ease of maintenance, and simplified construction. Surprisingly, despite the prevailing belief that HAWTs outperform VAWTs as individual units, VAWTs demonstrate higher power density when arranged in clusters. This phenomenon arises from positive wake interactions downstream of VAWTs, potentially enhancing the overall wind farm performances. In contrast, wake interactions negatively impact HAWT farms, reducing their efficiency. This paper extensively reviews the potential of VAWT clusters to increase energy output and reduce wind energy costs. A precise terminology is introduced More >

Jing Li, Bo Ning^*, Bin Li, Dezhi Qiu

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.12, pp. 2927-2939, 2024, DOI:10.32604/fdmp.2024.057388 - 23 December 2024

Abstract Offshore deepwater cementing generally faces more challenges than onshore cementing. Shallow formations in deepwater wells often exhibit low structural strength, high porosity, and are prone to shallow gas influx and hydrate formation. These factors require careful control of hydration heat. In this article, we examine the key factors influencing temperature fluctuations in the wellbore and develop a temperature model that accounts for the thermal effects related to cement slurry circulation and hydration. This model is then applied to a deepwater shallow formation cementing case study. The results show that: (1) When cement slurry is displaced More >

Jiarui Cheng^1,*, Yirong Yang¹, Sai Ye², Yucheng Luo¹, Bilian Peng¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.12, pp. 2887-2906, 2024, DOI:10.32604/fdmp.2024.057056 - 23 December 2024

Abstract During the implementation of CO₂ fracturing for oil and gas development, the force transfer effect caused by the unsteady flow of high-pressure CO₂ fluid can lead to forced vibration of the tubing and ensuing structural fatigue. In this study, a forced vibration analysis of tubing under CO₂ fracturing conditions is carried out by taking into account the fluid-structure coupling and related interaction forces by means of the method of characteristics (MOC). The results show that for every 1 m³/min increase in pumping displacement, the fluid flow rate increases up to 3.67 m/s. The flow pressure in the… More > Graphic Abstract

Junwei Han¹, Guohua Li¹, Wu Zhong¹, Yuchen Yang¹, Maoheng Li^2,3, Zhiwei Chen^2,3, Ruichang Ge^2,3, Lijuan Huang^2,3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.12, pp. 2757-2773, 2024, DOI:10.32604/fdmp.2024.056130 - 23 December 2024

Abstract A comprehensive method to evaluate the factors affecting the production capacity of horizontal wells in Carboniferous volcanic rocks after fracturing is investigated. A systematic approach combining gray correlation analysis, hierarchical analysis and fuzzy evaluation is proposed. In particular, first the incidence of reservoir properties and fracturing parameters on production capacity is assessed. These parameters include reservoir base geological parameters (porosity, permeability, oil saturation, waterproof height) as well as engineering parameters (fracture half-length, fracture height, fracture conductivity, fracture distance). Afterwards, a two-by-two comparison judgment matrix of sensitive parameters is constructed by means of hierarchical analysis, and More >