Haichao Zhou^*, Wei Zhang, Tinghui Huang, Haoran Li

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1113-1131, 2025, DOI:10.32604/fdmp.2025.064991 - 30 May 2025

Abstract The configuration of a spoiler plays a crucial role in the aerodynamics of a vehicle. In particular, investigating the impact of spoiler design on aerodynamic performance is essential for effectively reducing drag and optimizing efficiency. This study focuses on the 35° Ahmed body as the test model and examines six different spoiler types mounted on its slant surface. Using the Lattice Boltzmann Method (LBM) in XFlow and the Large Eddy Simulation (LES) technique, the aerodynamic effects of these spoilers were analyzed. The numerical approach was validated against published experimental data. Results indicate that aerodynamic drag More >

K. Sinivasan¹, N. Vishnu Ganesh^1,*, G. Hirankumar², M. Al-Mdallal Qasem^3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1029-1049, 2025, DOI:10.32604/fdmp.2025.064503 - 30 May 2025

Abstract In this study, an analytical investigation is carried out to assess the impact of magnetic field-dependent (MFD) viscosity on the momentum and heat transfers inside the boundary layer of a Jeffrey fluid flowing over a horizontally elongating sheet, while taking into account the effects of ohmic dissipation. By applying similarity transformations, the original nonlinear governing equations with partial derivatives are transformed into ordinary differential equations. Analytical expressions for the momentum and energy equations are derived, incorporating the influence of MFD viscosity on the Jeffrey fluid. Then the impact of different parameters is assessed, including magnetic More >

Yan Xiong¹, Xiangnan Song¹, Jiawei Lu¹, Lei Liu², Yaru Yan³, Xuemin Ye^3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1063-1077, 2025, DOI:10.32604/fdmp.2025.063769 - 30 May 2025

Abstract Enhancing the fermentation efficiency of waste in waste warehouses is pivotal for accelerating the pyrolysis process and minimizing harmful gas emissions. This study proposes an integrated approach, combining hot air injection with dual atomizing nozzles, for the thermal treatment of waste piles. Numerical simulations are employed to investigate the influence of various parameters, namely, nozzle height, nozzle tilt angle, inlet air velocity and air temperature, on the droplet diffusion process, spread area, droplet temperature, and droplet size distribution. The results show that reducing the nozzle height increases the temperature of droplets upon their deposition on… More > Graphic Abstract

Zhengzheng Cao¹, Shuaiyang Zhang¹, Cunhan Huang^2,*, Feng Du^3,4, Zhenhua Li^3,4, Shuren Wang¹, Wenqiang Wang^3,4, Minglei Zhai^3,4

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1007-1028, 2025, DOI:10.32604/fdmp.2025.062738 - 30 May 2025

Abstract Karst collapse columns typically appear unpredictably and without a uniform spatial arrangement, posing challenges for mining operations and water inrush risk assessment. As major structural pathways for mine water inrush, they are responsible for some of the most frequent and severe water-related disasters in coal mining. Understanding the mechanisms of water inrush in these collapse columns is therefore essential for effective disaster prevention and control, making it a key research priority. Additionally, investigating the developmental characteristics of collapse columns is crucial for analyzing seepage instability mechanisms. In such a context, this paper provides a comprehensive… More > Graphic Abstract

Fengxia Shi^1,2, Pengcheng Wang^1,*, Haonan Zhan¹, Xiangyun Shi¹

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1221-1238, 2025, DOI:10.32604/fdmp.2025.062244 - 30 May 2025

Abstract To investigate the impact of guide vane geometry—specifically, outlet angle, blade count, and radial height—on the performance of a Pump as Turbine (PAT), radial guide vanes were introduced upstream of the impeller in an IS80-50-315 low-specific-speed centrifugal PAT. Using an orthogonal test design, numerical simulations were conducted on 16 different PAT configurations, and the influence of vane geometry on performance was analyzed through a range analysis to determine the optimal parameter combinations. The results indicate that the number of guide vane blades significantly affects both the hydraulic efficiency and water head of the PAT under More >

Denis Polezhaev^*, Alexey Vjatkin, Victor Kozlov

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1051-1061, 2025, DOI:10.32604/fdmp.2025.062000 - 30 May 2025

Abstract The dynamics of fluid and non-buoyant particles in a librating horizontal annulus is studied experimentally. In the absence of librations, the granular material forms a cylindrical layer near the outer boundary of the annulus and undergoes rigid-body rotation with the fluid and the annulus. It is demonstrated that the librational liquefaction of the granular material results in pattern formation. This self-organization process stems from the excitation of inertial modes induced by the oscillatory motion of liquefied granular material under the influence of the gravitational force. The inertial wave induces vortical fluid flow which entrains particles More > Graphic Abstract

Zhi Yang^1,2, Xiaohui Zhang^1,2,*, Xinting Tong³, Yutang Zhao⁴, Teng Xia^1,2, Hua Wang^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1133-1150, 2025, DOI:10.32604/fdmp.2025.061737 - 30 May 2025

Abstract In bottom-blown copper smelting processes, oxygen-enriched air is typically injected into the melt through a lance, generating bubbles that ascend and agitate the melt, enhancing mass, momentum, and heat transfer within the furnace. The melt’s viscosity, which varies across reaction stages, and the operating conditions influence bubble size and dynamics. This study investigates the interplay between melt viscosity and bubble diameter on bubble motion using numerical simulations and experiments. In particular, the volume of fluid (VOF) method and Ω-identification technique were employed to analyze bubble velocity, deformation, trajectories, and wake characteristics. The results showed that More >

Shiyao Peng¹, Hanwen Zhang¹, Chong Chai¹, Shilong Xue², Xiaobin Zhang^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1099-1112, 2025, DOI:10.32604/fdmp.2025.060452 - 30 May 2025

Abstract The diffusion of hydrogen-blended natural gas (HBNG) from buried pipelines in the event of a leak is typically influenced by soil properties, including porosity, particle size, temperature distribution, relative humidity, and the depth of the pipeline. This study models the soil as an isotropic porous medium and employs a CFD-based numerical framework to simulate gas propagation, accounting for the coupled effects of soil temperature and humidity. The model is rigorously validated against experimental data on natural gas diffusion in soil. It is then used to explore the impact of relevant parameters on the diffusion behavior… More >

Yangyang Cao, Jiye Zhang^*, Jiawei Shi, Yao Zhang

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1079-1098, 2025, DOI:10.32604/fdmp.2025.060429 - 30 May 2025

Abstract The pantograph area is a critical source of aerodynamic noise in high-speed trains, generating noise both directly and through its cavity, a factor that warrants considerable attention. One effective method for reducing aerodynamic noise within the pantograph cavity involves the introduction of a jet at the leading edge of the cavity. This study investigates the mechanisms driving cavity aerodynamic noise under varying jet velocities, using Improved Delayed Detached Eddy Simulation (IDDES) and Ffowcs Williams-Hawkings (FW-H) equations. The numerical simulations reveal that an increase in jet velocity results in a higher elevation of the shear layer… More >

Qi Deng¹, Qi Ruan², Bo Zeng¹, Qiang Liu³, Yi Song¹, Shen Cheng¹, Huiying Tang^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1201-1219, 2025, DOI:10.32604/fdmp.2025.060311 - 30 May 2025

Abstract Over more than a decade of development, medium to deep shale gas reservoirs have faced rapid production declines, making sustained output challenging. To harness remaining reserves effectively, advanced fracturing techniques such as infill drilling are essential. This study develops a complex fracture network model for dual horizontal wells and a four-dimensional in-situ stress evolution model, grounded in elastic porous media theory. These models simulate and analyze the evolution of formation pore pressure and in-situ stress during production. The investigation focuses on the influence of infill well fracturing timing on fracture propagation patterns, individual well productivity, and… More >