Qingyun Zeng^1,2, Mingxin Zheng^1,*, Dan Huang²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.12, pp. 2981-3005, 2023, DOI:10.32604/fdmp.2023.029427

Abstract A complex interface exists between water flow and solid particles during hydraulic soil erosion. In this study, the particle discrete element method (DEM) has been used to simulate the hydraulic erosion of a granular soil under moving bed conditions and surrounding terrain changes. Moreover, the weakly compressible smoothed particle hydrodynamics (WCSPH) approach has been exploited to simulate the instability process of the free surface fluid and its propagation characteristics at the solid–liquid interface. The influence of a suspended medium on the water flow dynamics has been characterized using the mixed viscosity concept accounting for the solid–liquid mixed particle volume ratio.… More > Graphic Abstract

Youhao Wang¹, Chuntian Zhe¹, Chang Guo², Jinpeng Li³, Jinheng Li³, Shen Cheng², Zitian Wu¹, Suoying He¹, Ming Gao^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.12, pp. 2965-2980, 2023, DOI:10.32604/fdmp.2023.029292

Abstract Flow channels with a variable cross-section are important components of piping system and are widely used in various fields of engineering. Using a finite element method and modal analysis theory, flow-induced noise, mode shapes, and structure-borne noise in such systems are investigated in this study. The results demonstrate that the maximum displacement and equivalent stress are located in the part with variable cross-sectional area. The average excitation force on the flow channel wall increases with the flow velocity. The maximum excitation force occurs in the range of 0–20 Hz, and then it decreases gradually in the range of 20–1000 Hz.… More >

Zhongshuai Chen^1,2, Hongjian Ni^1,*, Xueliang Pei², Yu Gao³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.12, pp. 2953-2963, 2023, DOI:10.32604/fdmp.2023.029491

Abstract The actuator is a key component of the creaming tool in drilling applications. Its jet performances determine the effective reaming efficiency. In this work, a new selective reaming tool is proposed and the RNG k-ε turbulence model is used to calculate its internal and external flow fields. In particular, special attention is paid to the design of the flushing nozzle. The results show that the jet originating from the flushing nozzle has a significant influence on rock cutting and blade cooling effects. In turn, the jet performances depend on geometric structure of the creaming actuator. In this framework, a conical-cylindrical… More >

Ping Lv¹, Jiufei Liu², Mengran Xu^3,*, Hui Tian^3,4, Huajie Liu³, Yuhuan Bu³, Zhuang Cai³, Junfeng Qu⁵

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2907-2921, 2023, DOI:10.32604/fdmp.2023.029304

Abstract Cementing carbonate reservoirs is generally a difficult task. The so-called thixotropic cement slurry has gained considerable attention in this regard as it can help to fix some notable problems. More precisely, it can easily fill the leakage layer; moreover, its gelling strength can grow rapidly when pumping stops, thereby increasing the resistance to gas channeling, effectively preventing this undesired phenomenon in many cases. High-temperature thixotropic cement slurry systems, however, are still in an early stage of development and additional research is needed to make them a viable option. In the present study, using a self-developed composite high-temperature thixotropic additive as… More >

Fulai Cao^1,*, Yanpu Chao^1,*, Hao Yi^2,3, Shuai Lu¹, Chengshui Guo⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2891-2905, 2023, DOI:10.32604/fdmp.2023.029243

Abstract The properties of droplets produced by existing on-demand injection systems are typically determined by the nozzle diameter, i.e., only droplets with size larger than this diameter can be obtained. To solve this problem, a system for electric field-driven droplet injection and deposition was developed, and the related performances were compared with those of a standard pneumatic system. The results show that the diameter of droplets generated accordingly can be significantly smaller than the nozzle diameter. In particular, the effects of frequency and duty ratio on the number of droplets were studied by assuming microcrystalline wax as work material. A deposition… More > Graphic Abstract

Karema A. Hamad^*, Yasser A. Mahmood

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2863-2875, 2023, DOI:10.32604/fdmp.2023.029049

Abstract The cooling of a (pebble bed) spent fuel in a high-temperature gas-cooled reactor (HTGR) is adversely affected by an increase in the temperature of the used gas (air). To investigate this problem, a configuration consisting of three copper spheres arranged in tandem subjected to a forced mist flow inside a cylindrical channel is considered. The heat transfer coefficients and related variations as a function of Reynolds number are investigated accordingly. The experimental results show that when compared to those with only airflow, the heat transfer coefficient of the spherical elements with mist flow (j = 112 kg/m² hr, Re =… More >

Linjuan Zeng¹, Daogang Cai¹, Yunhai Zhao^1,*, Changqing Ye¹, Chengcheng Luo²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2813-2825, 2023, DOI:10.32604/fdmp.2023.026190

Abstract The flow behavior of shale gas horizontal wells is relatively complex, and this should be regarded as the main reason for which conventional pipe flow models are not suitable to describe the related dynamics. In this study, numerical simulations have been conducted to determine the gas-liquid distribution in these wells. In particular, using the measured flow pressure data related to 97 groups of shale gas wells as a basis, 9 distinct pipe flow models have been assessed, and the models displaying a high calculation accuracy for different water-gas ratio (WGR) ranges have been identified. The results show that: (1) The… More >

Jin Cai¹, Xiangwei Kong^1,*, Mingzhu Yu^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2791-2812, 2023, DOI:10.32604/fdmp.2023.029692

Abstract Iron ore sintering is a pre-treatment technology by which ore fines are converted into porous and permeable sinters, which are the used in blast furnaces. This process can be adversely affected by air leakage phenomena of various types. As experimental measurements are relatively difficult and often scarcely reliable, here a theoretical model based on typical fluid-dynamic concepts and relationships is elaborated. Through the analysis of two extreme cases, namely, those in which leakage is due to a small hole or a full rupture, a generalized hole-bed model is introduced, which for the first time also includes a complete bed permeability… More > Graphic Abstract

Muayad M. Hasan^1,*, Firas K. Al-Zuhairi², Anfal H. Sadeq¹, Rana A. Azeez¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2827-2835, 2023, DOI:10.32604/fdmp.2023.027746

Abstract Solvents are generally used to reduce the viscosity of heavy crude oil and ultimately enhance oil recovery. Recently, a new method has been introduced where nanoparticles (NPs) are exploited to induce enhanced oil recovery owing to their ability to improve the mobility ratio, dampen the interfacial tension, and alter rock wettability. This study investigated the integration of nano-alumina (Al₂O₃) NPs with an n-hexane solvent. In particular, a Brookfield viscometer has been used to measure the crude oil viscosity and it has been found that NPs can effectively lead to a significant decrease in the overall oil viscosity (70 cp using… More >

Juanjuan Wang^*, Jiangping Nan, Yanan Wang

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2761-2775, 2023, DOI:10.32604/fdmp.2023.021175

Abstract The main objective of this study is the technical optimization of a Shell-and-Tube Heat Exchanger (STHE). In order to do so, a simulation model is introduced that takes into account the related gas-phase circulation. Then, simulation verification experiments are designed in order to validate the model. The results show that the temperature field undergoes strong variations in time when an inlet wind speed of 6 m/s is considered, while the heat transfer error reaches a minimum of 5.1%. For an inlet velocity of 9 m/s, the heat transfer drops to the lowest point, while the heat transfer error reaches a… More >