Abdulmajeed D. Aldabesh¹, P. K. Pattnaik², S. Jena³, S. R. Mishra⁴, Mouna Ben Henda⁵, Iskander Tlili^5,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 205-222, 2022, DOI:10.32604/fdmp.2022.017899

Abstract Free convection of a viscous electrically conducting liquid past a vertical stretching surface is investigated in the presence of a transverse magnetic field. Natural convection is driven by both thermal and solutal buoyancy. The original partial differential equations governing the problem are turned into a set of ordinary differential equations through a similar variables transformation. This alternate set of equations is solved through a Differential Transform Method (DTM) and the Pade approximation. The response of the considered physical system to the non-dimensional parameters accounting for the relative importance of different effects is assessed considering different situations. More >

Pengfei Wang^1,2, Xiangyang Zhang^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 271-283, 2022, DOI:10.32604/fdmp.2022.017882

Abstract A mixture of fault gouge and rubble taken out from a fault zone is used to prepare a S-RM (Soil-Rock Mixture) sample with rock block proportions of 20%, 30%, 40%, 50%, 60% and 70%, respectively. A GDS triaxial test system is used accordingly to measure the seepage characteristics of such samples under different loading and unloading confining pressures in order to determine the variation law of the permeability coefficient. The test results show that: (1) The permeability coefficient of the S-RM samples decreases as the pressure increases, and the decrease rate of this coefficient in the initial stage of confining… More >

Tiankui Guo^1,*, Zhilin Luo¹, Shanbo Mou², Ming Chen¹, Yuanzhi Gong³, Jianhua Qin⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 431-447, 2022, DOI:10.32604/fdmp.2022.017861

Abstract Although the dynamics of proppant (small ceramic balls used to prevent opened fractures from closing on the release of pressure) have been the subject of several numerical studies over recent years, large-scale inclined fractures exist in unconventional reservoirs for which relevant information is still missing. In the present study, this problem is investigated numerically considering the influence of several relevant factors such as the fracture roughness, inclination, the proppant particle size, the injection rate and the fluid viscosity. The results show that a rough wall enables the proppant to travel farther and cover larger areas. The inclination angle has little… More >

Meng Song^1,*, Yuncai Liu², Zhen Wang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 313-327, 2022, DOI:10.32604/fdmp.2022.017737

Abstract The purpose of the study is to implement a new model based on the Navier-Stokes equations for the characterization of landslide sediments interacting with a moving fluid. The model is implemented by combining Hypermesh, the LS-DYNA software and MATLAB. The results show that the main factors affecting the permeability of landslide sediments are the genetic mechanism, the structure and composition of materials, material lithology, and stress. The characteristics and mechanism of permeability changes are determined by adjusting the water levels of fluids. It is found that the permeability of landslide sediments increases at the front and decreases in the middle… More >

Yajuan Jia¹, Lisha Shang¹, Jiangping Nan¹, Guangping Hu², Zhigang Fang^3,4,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 329-344, 2022, DOI:10.32604/fdmp.2022.017734

Abstract The flow past a fixed single transmission conductor and the related heat transfer characteristics are investigated using computational fluid dynamics and a relevant turbulence model. After validating the method through comparison with relevant results in the literature, this thermofluid-dynamic problem is addressed considering different working conditions. It is shown that the resistance coefficient depends on the Reynolds number. As expected, the Nusselt number is also affected by Reynolds number. In particular, the Nusselt number under constant heat flux is always greater than that under a constant wall temperature. More >

Fang Jin^*, Dong Zhou, Liying Zhu

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 285-302, 2022, DOI:10.32604/fdmp.2022.017593

Abstract The purpose is to study the microstructure and macroscopic fluid-dynamic behavior of soft soil after it has been subjected to a seepage consolidation procedure. First, the microscopic pore structure of soft clay is quantitatively studied by a scanning electron microscope technique. Second, the average contact area rate of soil particles is obtained employing statistical analysis applied to microscopic images of soft soil, and the macroscopic porosity of soft clay is determined through an indoor geotechnical test. Finally, mathematical relationships are introduced by fitting the results of the test. The results show that the unmodified empirical equation for the permeability coefficient… More >

Yueli Feng^1,2, Yuetian Liu^1,2,*, Xiaolong Mao^1,2, Jian Chen^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 371-393, 2022, DOI:10.32604/fdmp.2022.017534

Abstract This study clarifies the seepage characteristics of complex fractured pressure-sensitive reservoirs, and addresses a common technological problem, that is the alteration of the permeability degree of the reservoir bed (known to be responsible for changes in the direction and velocity of fluid flows between wells). On the basis of a new pressure-sensitive equation that considers the fracture directional pressure-sensitive effect, an oil-gas-water three-phase seepage mathematical model is introduced, which can be applied to pressure-sensitive, full-tensor permeability, ultralow-permeability reservoirs with fracture-induced anisotropy. Accordingly, numerical simulations are conducted to explore the seepage laws for ultralow-permeability reservoirs. The results show that element patterns… More >

Jiawei Shi¹, Shuai Ge¹, Xiaozhen Sheng^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 463-480, 2022, DOI:10.32604/fdmp.2022.017508

Abstract In order to understand the mechanism by which a pantograph can generate aerodynamic noise and grasp its far-field characteristics, a simplified double-strip pantograph is analyzed numerically. Firstly, the unsteady flow field around the pantograph is simulated in the frame of a large eddy simulation (LES) technique. Then the location of the main noise source is determined using surface fluctuating pressure data and the vortex structures in the pantograph flow field are analyzed by means of the Q-criterion. Based on this, the relationship between the wake vortex and the intensity of the aerodynamic sound source on the pantograph surface is discussed.… More >

Jian Song^*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 345-354, 2022, DOI:10.32604/fdmp.2022.017382

Abstract Computational Fluid Dynamics is used to assess the thermal (heat transfer) performances of an automobile engine considering different grille opening and closing degrees. For this purpose the entire vehicle is modelled and three fundamental aspects are examined, namely, the open area of the air intake grille, the position of the upper and lower grilles and their shape. The results show that the opening area and position of the grille have some influence also on the aerodynamic characteristics of the automobile. With an increase in the opening angle of the grille, the C_D (Drag Coefficient) value of the whole vehicle becomes… More >

Jianhui Yang¹, Kai Shen¹, Shoudong Pan², Shuren Wang^3,*, Zhengsheng Zou³

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 243-255, 2022, DOI:10.32604/fdmp.2022.016677

Abstract The large deformation of soft rock tunnel is one of the key problems to be overcome in the tunnel construction stage. In the present study, the deformation mechanism of a representative tunnel and some related countermeasures are investigated using field tests and engineering geological analysis. Owing to the scarce performances of methods based on other criteria such as small pipe spacing, anchor bolt length and steel frame spacing, a new support scheme is implemented and optimized. Results show that shear failure and bedding sliding are produced under high horizontal stress conditions. The low strength of the surrounding rock results in… More >