Guochen Xu^*

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2024.048337

Abstract Microscopic pore structure in continental shale oil reservoirs is characterized by small pore throats and complex micro-structures. The adsorption behavior of hydrocarbons on the pore walls exhibits unique physical and chemical properties. Therefore, studying the adsorption morphology of hydrocarbon components in nanometer-sized pores and clarifying the exploitation limits of shale oil at the microscopic level are of great practical significance for the efficient development of continental shale oil. In this study, molecular dynamics simulations were employed to investigate the adsorption characteristics of various single-component shale oils in inorganic quartz fissures, and the influence of pore size and shale oil hydrocarbon… More >

Yu Wang^1,2, Mengyang Ma^1,2,*, Yong Long^1,2, Qingxiang Zhao^1,2, Zhifei Cheng^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2024.048695

Abstract

Shrinkage-induced cracking is a common issue in concrete structures, where the formation of cracks not only affects the aesthetic appearance of concrete but also potentially reduces its durability and strength. In this study, the effect of ceramsite sand addition on the properties of a ternary system of cement-ground granulated blast furnace slag (GGBFS)-phosphogypsum (PG) is investigated. In particular, the fluidity, rheology, hydration heat, compressive strength, autogenous shrinkage, and drying shrinkage of the considered mortar specimens are analyzed. The results indicate that an increase in PG content leads to a decrease in fluidity, higher viscosity, lower exothermic peak, and lower compressive… More >

Zhihui Du¹, Mengge Yu^1,*, Jiali Liu², Xiulong Yao¹

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2024.047315

Abstract Snow interacting with a high-speed train can cause the formation of ice in the train bogie region and affect its safety. In this study, a wind-snow multiphase numerical approach is introduced for high-speed train bogies on the basis of the Euler-Lagrange discrete phase model. A particle-wall impact criterion is implemented to account for the presence of snow particles on the surface. Subsequently, numerical simulations are conducted, considering various snow particle diameter distributions and densities. The research results indicate that when the particle diameter is relatively small, the distribution of snow particles in the bogie cavity is relatively uniform. However, as… More >

Yuanjun Dai^1,4,*, Dong Wang¹, Xiongfei Liu², Weimin Wu³

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2024.046158

Abstract To enhance the aerodynamic performance of wind turbine blades, this study proposes the adoption of a bionic airfoil inspired by the aerodynamic shape of an eagle. Based on the blade element theory, a non-uniform extraction method of blade elements is employed for the optimization design of the considered wind turbine blades. Moreover, Computational Fluid Dynamics (CFD) is used to determine the aerodynamic performances of the eagle airfoil and a NACA2412 airfoil, thereby demonstrating the superior aerodynamic performance of the former. Finally, a mathematical model for optimizing the design of wind turbine blades is introduced and a comparative analysis is conducted… More >

Tiantian Yu¹, Youping Lv¹, Hao Zhong², Ming Liu¹, Pingyuan Gai¹, Zeju Jiang¹, Peng Zhang¹, Xingkai Zhang^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2024.049035

Abstract A new measurement device, consisting of swirling blades and capsule-shaped throttling elements, is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow. The swirling blades are used to transform the complex flow pattern into a forced annular flow. Drawing on the research of existing blockage flow meters and also exploiting the single-phase flow measurement theory, a formula is introduced to measure the phase-separated flow of gas and liquid. The formula requires the pressure ratio, Lockhart-Martinelli number (L-M number), and the gas phase Froude number. The unknown parameters appearing in the formula are… More >

Yun Ren^1,*, Lianzheng Zhao², Xiaofan Mo², Shuihua Zheng², Youdong Yang¹

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2024.046274

Abstract A coupled Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) approach is used to calculate the interaction of a flexible rag transported by a fluid current with a fixed solid cylinder. More specifically a hybrid Eulerian-Lagrangian approach is used with the rag being modeled as a set of interconnected particles. The influence of various parameters is considered, namely the inlet velocity (1.5, 2.0, and 2.5 m/s, respectively), the angle formed by the initially straight rag with the flow direction (45°, 60° and 90°, respectively), and the inlet position (90, 100, and 110 mm, respectively). The results show that the flow rate has… More > Graphic Abstract

Chenkai Hong^1,2,*, Zhongda Lyu^2,*, Fei Wang², Zhuo Zhao², Lei Wang²

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2024.042685

Abstract To scrutinize the characteristics of wave–current loads on a bridge shuttle-shaped cap–pile foundation, a 1:125 test model was considered in a laboratory flume. The inline, transverse and vertical wave–current forces acting on the shuttle-shaped cap–pile group model were measured considering both random waves and a combination of random waves with a current. The experimental results have shown that the wave–current forces can be well correlated with the wave height, the wavelength, the current velocity, the incident direction and the water level in the marine environment. An increase in the current velocity can lead to a sharp increase in the inline… More >

Dmitry Bratsun^*, Kirill Kostarev

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2024.048206

Abstract

Swarms of self-organizing bots are becoming important elements in various technical systems, which include the control of bacterial cyborgs in biomedical applications, technologies for creating new metamaterials with internal structure, self-assembly processes of complex supramolecular structures in disordered media, etc. In this work, we theoretically study the effect of sudden fluidization of a dense group of bots, each of which is a source of heat and follows a simple algorithm to move in the direction of the gradient of the global temperature field. We show that, under certain conditions, an aggregate of self-propelled bots can fluidize, which leads to a… More > Graphic Abstract

Wei Chen^*, Dingdan Liu, Yue Liang

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2024.046335

Abstract This study focuses on the effect of ultrafine waste glass powder on cement strength, gas permeability and pore structure. Varying contents were considered, with particle sizes ranging from 2 to 20 μm. Moreover, alkali activation was considered to ameliorate the reactivity and cementitious properties, which were assessed by using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and specific surface area pore size distribution analysis. According to the results, without the addition of alkali activators, the performance of glass powder mortar decreases as the amount of glass powder increases, affecting various aspects such as strength and resistance to gas permeability.… More >

Xin Liu^1,*, Kai Yan², Bo Fang³, Xiaoyu Sun³, Daqiang Feng⁴, Li Yin⁵

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2024.047922

Abstract In response to the complex characteristics of actual low-permeability tight reservoirs, this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs, considering complex boundary shapes. Utilizing radial basis function point interpolation, the method approximates shape functions for unknown functions within the nodal influence domain. The shape functions constructed by the aforementioned meshless interpolation method have δ-function properties, which facilitate the handling of essential aspects like the controlled bottom-hole flow pressure in horizontal wells. Moreover, the meshless method offers greater flexibility and freedom compared to grid cell discretization, making it simpler to discretize complex geometries. A… More >