Article
Mechanics
Xiaoyong Cheng, Zhixian Cao, Ji Li, Alistair Borthwick
Summary: This study investigates the settling behavior of non-spherical particles through numerical simulations, finding that non-spherical particles experience larger drag and attain lower terminal velocities compared to equivalent spheres. The effect of particle shape on terminal velocity is more significant at relatively large particle Reynolds numbers, while it is less pronounced at smaller Reynolds numbers. Additionally, empirical correlations are derived for the characteristic time and displacement of particle settling, showing different trends in the Stokes and intermediate regimes.
Article
Engineering, Chemical
Muhammad Uzair, M. Danyal Qasim, M. Aashan Bhatti, Ali Abbas Zaidi, John J. Molina, Ryoichi Yamamoto, Adnan Hamid
Summary: The recently updated Smooth Profile Method (SPM) is validated for rigid particles settling in a Newtonian fluid. Non-spherical particles, including regular and irregular shapes, are generated by joining spherical beads. Drag and lift coefficients are calculated for regular-shaped particles, and good agreement with literature is observed. New correlations for fiber, disk, and scalene prolate particles are suggested.
Article
Mechanics
Giorgia Tagliavini, Mark McCorquodale, Chris Westbrook, Markus Holzner
Summary: The study reveals that the complex shape of snow particles can lead to intricate wake phenomena, affecting their drag coefficient and falling attitudes. Findings suggest that different shapes and wake flows have varying impacts on the drag coefficient at different Reynolds numbers.
Article
Mechanics
Zhe Wang, Jianzhi Yang, Helge I. Andersson, Xiaowei Zhu, Minghou Liu, Liping Wang, XianMing Lu
Summary: Numerical simulations were conducted to study the flow around an inclined 5:2 prolate spheroid in a uniform freestream. Eight flow regimes were identified, with three new modes being reported for the first time. It was found that the elongated body can delay the onset of unsteadiness at small incidence angles.
Article
Mechanics
Zhe Wang, Jianzhi Yang, Helge Andersson, Xiaowei Zhu, Yuxin Wu, Liping Wang, Minghou Liu
Summary: This article numerically investigates the flow characteristics of an inclined 5:2 prolate spheroid in a uniform shear flow. Five different wake modes, including a new mode, are observed. The results show that increasing the shear rate suppresses wake transition, and at high shear rates, the flow can even transition from unsteady to steady state. Additionally, increasing the shear rate and Reynolds number leads to an increase in the time-averaged drag/lift coefficients and Strouhal number. The effect of a sign-change of the incidence angle of the prolate spheroid on wake evolution is also investigated.
Article
Nanoscience & Nanotechnology
Yuqi Wang, Zhengping Zhu, Ruifeng Hu, Lian Shen
Summary: This study conducts fully resolved direct numerical simulations to investigate the effects of fluctuating freestream flow on the drag force and wake characteristics of a stationary spherical particle. The results reveal that the direction of freestream flow fluctuation significantly influences the mean drag and drag fluctuation properties.
Article
Engineering, Environmental
Sathish K. P. Sanjeevi, Jean F. Dietiker, Johan T. Padding
Summary: Detailed simulations of flow around various prolate spheroids were conducted using the multi-relaxation time lattice Boltzmann method (LBM). Accurate correlations for average drag, lift, and torque coefficients were proposed based on the simulation data. These correlations can be extrapolated beyond the simulated regimes and were found to be more accurate compared to other correlations from literature.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Physics, Fluids & Plasmas
F. Cabrera, M. Z. Sheikh, B. Mehlig, N. Plihon, M. Bourgoin, A. Pumir, A. Naso
Summary: The precise description of the motion of anisotropic particles in a flow depends on the understanding of the force and torque acting on them. In this study, the settling motion of very elongated particles in a fluid was experimentally investigated, and the torque was found to have a simple angle dependence. The experimental results were compared with predictions from slender-rod and spheroid models, with the latter providing a better approximation for particles with an aspect ratio of 16.
PHYSICAL REVIEW FLUIDS
(2022)
Article
Engineering, Chemical
Patrick Fillingham, Ravi S. Vaddi, Andrew Bruning, Gunnar Israel, Igor V. Novosselov
Summary: This study introduces new relations for the aerodynamic forces on prolate-spheroidal particles attached to a surface, predicting drag, lift, and torque coefficients, which agree with the direct numerical simulations results.
Article
Engineering, Marine
Denghui Qin, Qiaogao Huang, Guang Pan, Yao Shi, Fuzheng Li, Peng Han
Summary: The hydrodynamic and noise characteristics of a blended-wing-body glider and a traditional Slocum glider are compared in this study. The blended-wing-body glider has a higher lift/drag ratio and lower noise level, making it suitable for ocean observation tasks.
Article
Mechanics
Wenqiang Shang, Hui Zhao, Dong Li, Kun Luo, Jianren Fan
Summary: This study investigates the flow past a sphere immersed in a flat-plate turbulent boundary layer using direct numerical simulations. The wake of the sphere was found to play an important role in the streamwise region, particularly at a gap ratio of 0.1. The presence of the sphere significantly affected turbulence statistics and the skin friction coefficient.
Article
Mechanics
B. Deussen, Y. Wang, M. Oberlack
Summary: This paper derives a closed system of equations using the Eulerian spatial averaging theory to model an active suspension. The derived equations include balance equations for mass, momentum, angular momentum, and orientation for both the fluid and solid phases. The paper also includes a numerical study to highlight the importance of the Saffman effect in active suspensions.
Article
Thermodynamics
Bo Yin, Yu Guan, Ao Wen, Nader Karimi, Mohammad Hossein Doranehgard
Summary: The study investigates the flow field around two tandem NACA 0012 airfoils in ground effect at a low Reynolds number relevant to pico-aerial vehicles. Results show that two tandem airfoils are more aerodynamically efficient than two isolated identical airfoils, especially when the gap height is positive. The aerodynamics of the tandem-airfoil system are strongly influenced by airfoil-to-airfoil interference and the presence of a laminar separation bubble.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Engineering, Marine
Guillaume Delefortrie, Wim Van Hoydonck, Katrien Eloot
Summary: This paper presents a mathematical model for predicting the force and torque on a ship's rudder during maneuvers in a harbor, with coefficients derived from captive model tests. The model is successfully applied in ship maneuvering simulators and will aid international research on ship maneuvering in shallow and confined waters.
JOURNAL OF MARINE SCIENCE AND TECHNOLOGY
(2022)
Article
Mechanics
Sheng Chen, Pinzhuo Chen, Jianhong Fu
Summary: This study uses particle-resolved direct numerical simulation to calculate the drag and lift forces on linear and irregular agglomerates formed by nano- and micrometer particles. Explicit expressions for the drag and lift coefficients are proposed, and the influence of agglomerate shape on the lift coefficient distribution is revealed.
Article
Computer Science, Interdisciplinary Applications
Rafik Ouchene, Mohammed Khalij, Anne Taniere, Boris Arcen
COMPUTERS & FLUIDS
(2015)
Article
Mechanics
B. Arcen, R. Ouchene, M. Khalij, A. Taniere
Article
Thermodynamics
B. Arcen, A. Taniere, M. Khalij
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2012)
Article
Mechanics
Rafik Ouchene, Juan Ignacio Polanco, Ivana Vinkovic, Serge Simoens
JOURNAL OF TURBULENCE
(2018)
Article
Mechanics
P. Dubs, M. Khalij, R. Benelmir, A. Tazibt
MECHANICS RESEARCH COMMUNICATIONS
(2011)
Article
Mechanics
Rafik Ouchene, Arnaud Erriguible, Stephane Vincent, Pascale Subra-Paternault
MECHANICS RESEARCH COMMUNICATIONS
(2013)
Article
Energy & Fuels
Karima Hijjaji, Nader Frikha, Slimane Gabsi, Abdelhamid Kheiri, Mohammed Khalij
Summary: This study proposes a modification for traditional solar stills by incorporating water spray and ambient air injection to enhance water-air contact area and increase productivity. A Response Surface Methodology (RSM) model is established to optimize evaporated water output, showing excellent agreement between predicted and experimental results. The main influencing parameters were identified as ambient air mass flow, saltwater temperature, sprayed water mass flow, and sprayer height. Hourly productivity ranged from 1.91 to 7.9 kg/h m(2) for water temperatures between 40 and 70 degrees C.
INTERNATIONAL JOURNAL OF ENERGY AND ENVIRONMENTAL ENGINEERING
(2021)
Proceedings Paper
Engineering, Mechanical
B. Arcen, A. Taniere, M. Khalij
THMT-12. PROCEEDINGS OF THE SEVENTH INTERNATIONAL SYMPOSIUM ON TURBULENCE, HEAT AND MASS TRANSFER
(2012)
Article
Engineering, Chemical
JP Carlier, M Khalij, B Oesterlé
AEROSOL SCIENCE AND TECHNOLOGY
(2005)
Article
Mechanics
A Tanière, M Khalij, B Oesterlé
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2004)
Article
Thermodynamics
M Khalij, S Moissette, P Gardin, JL Borean, B Oesterle
PROGRESS IN COMPUTATIONAL FLUID DYNAMICS
(2006)
Article
Engineering, Chemical
Ri Zhang, Shasha Zhang, Mengyan Ding
Summary: A thin liquid film method is proposed to evaluate sand erosion in annular flow. This method considers the direct interaction between the liquid film and gas core, as well as the entrainment and deposition of droplets. The erosion rate is calculated by considering the effects of liquid entrainment and particle velocity decay. The method is fully verified by comparing with experimental data.
Article
Engineering, Chemical
Yu Suo, Xianheng Su, Wenyuan He, Xiaofei Fu, Zhejun Pan
Summary: This research investigates the mechanical properties of sandstone-shale composite through orthogonal experimental method and discrete element simulation. The results show that different lithologies and thickness ratios can affect the strength and fracture mode of the composite rock samples.
Article
Engineering, Chemical
Maurizio Troiano, Andrea El Hassanin, Roberto Solimene, Alessia Teresa Silvestri, Fabrizio Scala, Antonino Squillace, Piero Salatino
Summary: This study investigates the potential of Fluidized Bed Finishing (FBF) for square flat AlSi10Mg specimens manufactured via Laser-Powder Bed Fusion (L-PBF) additive manufacturing technology. The results show that good finishing can be achieved using rotation-assisted tests, with a maximum reduction of surface roughness by 67%. Steel particles are found to be the most effective bed material.
Review
Engineering, Chemical
Ningbo Song, Wanzhong Yin, Jin Yao
Summary: Seawater's dissolved salts and minerals have various effects on the flotation process, including influencing the characteristics and behavior of flotation factors, as well as affecting the surface of sulfide minerals. In most cases, seawater has adverse effects on the flotation of sulfide minerals, but these effects can be mitigated by adjusting the reagents.
Article
Engineering, Chemical
Kaiqiao Wu, Shuxian Jiang, Victor Francia, Marc-Olivier Coppens
Summary: In rectangular and cylindrical annular fluidized beds, pulsating gas flow can create regular bubble patterns, overcoming challenges seen in conventional units. This study provides new opportunities for modularization of fluidized bed operations.
Article
Engineering, Chemical
Shuo Li, Huili Zhang, Jan Baeyens, Miao Yang, Zehao Li, Yimin Deng
Summary: The paper assesses the behavior of cohesive Geldart C-type particles when fluidized by air with the aid of vibration. It determines that mechanical vibration is a simple and effective method to improve the fluidity of cohesive particles during fluidization.
Article
Engineering, Chemical
Zhenfei Feng, Qingyuan Zhang, Shanpan Liang, Zhenzhou Li, Fangwen Guo, Jinxin Zhang, Ding Yuan
Summary: A new micro/mini-channel heat sink (MCHS) with a combined structure of longitudinal and transverse vortex generators is designed, using Al2O3 nanofluid as the working medium. The study explores the effects of transverse vortex generator shape and longitudinal vortex generator angle on the hydraulic and thermal characteristics, comprehensive performance, entropy generation, and exergy efficiency. The results show that the triangular transverse vortex generator improves the comprehensive performance and exergy efficiency. Combined with the longitudinal vortex generator, the MCHS achieves the best comprehensive performance, entropy generation, and exergy efficiency when the Reynolds number is 742.
Article
Engineering, Chemical
Kostas Giannis, Christoph Thon, Guoqing Yang, Arno Kwade, Carsten Schilde
Summary: This study presents a 3D convolutional neural network (3D-CNN) methodology for generating realistic 3D models of particles. The method trains on 2D projections of particle images to predict their 3D shapes, and evaluates the accuracy of the predictions using Fourier shape descriptors (FSDs). This methodology has wide applications in particle shape analysis.
Article
Engineering, Chemical
Zheng-qing Zhou, Lu-jia Chai, Yu-long Zhang, Ya-bin Wang, Ze-chen Du, Tian-yi Wang, Yu-zhe Liu
Summary: The dynamic oxidation and shell-breaking processes of aluminum nanoparticles (ANPs) during heating were studied using in situ transmission electron microscopy. The results revealed that the changes in shell thickness can be divided into three stages, and the active aluminum content of ANP decreased before shell-breaking.
Article
Engineering, Chemical
Fulei Chen, Huaqing Ma, Zihan Liu, Lianyong Zhou, Yongzhi Zhao
Summary: A particle breakage model based on the particle replacement scheme, using the polyhedral model to describe particles, is proposed in this work to accurately describe the breakage of a large number of particles. Additionally, a fast-cutting algorithm is proposed to reproduce the size distribution of progeny particles determined by the breakage model. The validation and simulation results show satisfactory accuracy, efficiency, and stability of the algorithm.
Review
Engineering, Chemical
Matteo Errigo, Christopher Windows-Yule, Massimiliano Materazzi, Dominik Werner, Paola Lettieri
Summary: Gas-solid fluidized-bed systems have advantages in terms of chemical reaction efficiency and temperature control, making them widely used in industrial applications. However, the design, scale-up, and optimization of these complex units are limited by the lack of deep physical understanding. Non-invasive and non-intrusive diagnostic techniques provide a way for researchers to study these systems without affecting the flow field or directly contacting the medium under study.
Article
Engineering, Chemical
Saeed Fateh, Mohammad Behshad Shafii, Mohammad Najafi, Cyrus Aghanajafi
Summary: Applying a magnetic field to ferrofluids alters their flow characteristics and enhances heat transfer. Through visualization and quantitative investigation, it is found that the magnetic field influences the flow patterns and velocity profiles, improving fluid mixing and vorticity magnitude.
Article
Engineering, Chemical
Lei Gao, Bingbing Wei, Xiaochuan Hu, Zaifeng Yao, Yiwen Fang, Xuejian Gao
Summary: In this study, a numerical model of sand triaxial test was established using discrete element software PFC3D, and an indoor triaxial test was conducted to calibrate the numerical model. The influence of microscopic parameters on the macroscopic mechanical response of sand was analyzed. The results showed that the friction coefficient had the greatest impact on the peak strength and residual strength of the sand's stress-strain curve, and it was positively correlated. The normal tangential stiffness ratio was negatively correlated, while the porosity and boundary flexibility stiffness had minimal influence on it.
Article
Engineering, Chemical
Xuan Liu, Jie Gong, Kai Jiang, Xiaojuan Lai, Yu Tian, Kang Zhang
Summary: This study aimed to improve the performance of lignite coal water slurries (CWSs) by synthesizing a series of three-arm amphiphilic block copolymers. By controlling the relative molecular weight, hydrophilic/hydrophobic ratio, and ionic group content, the apparent viscosity of CWSs was significantly reduced and the static stability was improved. Thermogravimetric testing and XPS analysis were conducted to reveal the mechanism behind the improved performance.
Article
Engineering, Chemical
Lanka Dinushke Weerasiri, Daniel Fabijanic, Subrat Das
Summary: Fluidization at low pressure offers significant benefits for the fine chemical industry. This study investigates the behavior of bubbles and bed expansion under low pressure conditions. It is found that lower pressure leads to larger bubbles, increased bubble quantity, and higher aspect ratio. The predictability is affected by the inhomogeneous fluidization, but low pressure fluidization can generate similar bubble sizes with lower fluidizing mass compared to atmospheric pressure.
