Article
Engineering, Chemical
Li Zhao, Qiang Zhou, Bolun Yang, Xiao Chen
Summary: Lattice Boltzmann simulations were used to investigate the drag force on fixed monodisperse spheres at low Reynolds numbers. The results showed that the solid volume fraction in the surrounding part had a significant impact on the drag force of the center particles, and this effect became more prominent as the solid volume fraction or the inhomogeneities of the central particles increased. A new drag model considering the surrounding influence was proposed, which showed promise in studying gas-solid interactions in flows with complex structures.
Article
Mechanics
H. Rahmani, H. Kumar, J. Greener, S. M. Taghavi
Summary: This study investigates the inertial flows of a yield stress fluid in a channel with a superhydrophobic groovy wall using numerical computations. The superhydrophobic wall is modeled with slip and stick arrays, while the viscoplastic rheology is modeled using the Bingham constitutive model. The study focuses on the effects of flow parameters on various flow variables and addresses the interplay between yield stress fluid rheology, wall superhydrophobicity, and flow inertia.
Article
Mechanics
Kexue Zhang, Liyuan Xu, Yunyun Li, Fabio Marchesoni, Jun Wang, Guodong Xia
Summary: This study investigates the self-propulsion of a Janus particle suspended in a dilute gas at equilibrium and confirms the analytical results through numerical simulations.
Article
Engineering, Aerospace
Mingyang Zheng, Chao Chen, Xiaodong Li
Summary: This study investigates the factors influencing acoustic liner drag, including geometric structures, Mach numbers, and structural characteristics. Experimental results show that Mach number has a critical influence on acoustic liner drag, and the geometric features of the liner can effectively reduce the drag.
AEROSPACE SCIENCE AND TECHNOLOGY
(2022)
Article
Mechanics
Debanjan Banerjee, Sukumar Pati, Pankaj Biswas
Summary: This study investigates the thermal transport and fluid flow behavior of pressure-driven flow on hydrophobic surfaces, taking into account the influence of surface charge on slip. The results show that the flow velocity decreases, with the decrement being more significant for lower n values, higher magnitude of zeta potential, and thicker electric double layer (EDL). Additionally, there is a strong interplay between the rheology of the fluid and EDL thickness in determining the variation of the Nusselt number.
Article
Mechanics
Takahiro Yatabe, Tetsuya Kanagawa, Takahiro Ayukai
Summary: The effects of a translation of bubbles and a drag force acting on bubbles on wave propagation in bubbly flows have been theoretically and numerically investigated. The translation of bubbles enhances the nonlinear effect of waves, while the drag force contributes to the nonlinear and dissipation effects of waves. Results show that the dissipation of waves due to drag force differs from that caused by acoustic radiation.
Article
Chemistry, Multidisciplinary
Matthew Mecklenburg, Brian T. Zutter, Xin Yi Ling, William A. Hubbard, B. C. Regan
Summary: By mapping the density of an aluminum nanowire, it was discovered that an electrical current can cause Joule heating, resulting in tension upwind and compression downwind. Surprisingly, the pressure inside the wire returns to its ambient value despite high current densities, indicating new opportunities for improving IC design resistant to electromigration.
Review
Forestry
Raquel Goncalves, Camila Linhares, Takashi Yojo
Summary: This paper reviews the factors that affect the calculation of drag coefficient in trees. Drag force caused by wind is a common reason for tree fall, and the drag coefficient is a key parameter for calculating this force. Plants have different mechanisms for reacting to wind pressure compared to civil structures, as they have complex architectures and compositions. The dynamic nature of wind and the tree's response to it further add to the complexity of determining the drag coefficient. The scattered existing information and variations in analysis methods make it challenging to accurately measure and calculate the drag coefficient.
TREES-STRUCTURE AND FUNCTION
(2023)
Article
Engineering, Chemical
Mingjian Hu, Yin Wang, Yewei Li, Ziyi Pang, Yubin Ren
Summary: This study develops a drag force model by utilizing genetic programming (GP) and focusing on the voidage function. The model was developed based on a systematic laboratory seepage tests on porous media with different materials. The results indicate that the developed drag force model by GP method has good performance in predicting the drag behavior of particles, and the influencing factors such as gradation coefficient, porosity, and shape coefficient significantly affect the seepage characteristics of the porous media. The proposed model can be used to analyze the flow characteristics of porous media in the field of geotechnical and ocean engineering.
Article
Mathematics, Interdisciplinary Applications
Zhenjiang Zhao, Ling Bai, Weidong Shi, Linjian Li, Mahmoud A. El-Emam, Ramesh Agarwal, Ling Zhou
Summary: This study investigates the influence of microscopic forces and energy on the macroscopic motion of particles in a dense gas-solid fluidized bed using the CFD-DEM coupling approach. Experimental validation shows that drag force is positively correlated with inlet flow rate and particle diameter, tangential contact force dominates near the inlet, fluid pressure gradient force can be neglected at certain positions, and particle energy is positively correlated with inlet flow rate and particle diameter due to bubble formation.
COMPUTATIONAL PARTICLE MECHANICS
(2023)
Article
Engineering, Civil
Hoyeoul Park, Chan-Gyu Kim, Kibum Kim, Sang-hun Lee
Summary: This study developed a real-time state estimation of the skydiving physics model using the unscented Kalman filter (UKF). The UKF was able to predict falling altitudes with various error ranges and was influenced by fluctuations in falling velocity and missing datasets. The study also monitored wind velocity and heart rate, and found low correlations between skydiving activities and heart rate.
JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS
(2022)
Article
Energy & Fuels
Paulo Guimaraes de Moraes, Luiz Antonio Alcantara Pereira
Summary: This study investigates the effects of surface roughness on the aerodynamic loads and vortex shedding frequency of two circular cylinders in tandem arrangement. The relative roughness heights were found to significantly influence the behavior of flows past the two cylinders, including drag reduction, intermittence in vortex shedding, and wake destruction.
Article
Physics, Multidisciplinary
Cui Jie, Su Jun-Jie, Wang Jun, Xia Guo-Dong, Li Zhi-Gang
Summary: Thermophoresis refers to the movement of small particles in a fluid with non-uniform temperature, due to temperature gradients. It has significant applications in various fields, and its accuracy is crucial. Studies have shown that the validity of thermophoretic theories depends on gas-particle interactions and temperature conditions. By considering nonrigid-body interactions and adjusting particle size, theoretical results for thermophoretic force align well with simulations.
ACTA PHYSICA SINICA
(2021)
Article
Mechanics
Jana Wedel, Mitja Strakl, Jure Ravnik, Paul Steinmann, Matjaz Hribersek
Summary: In the case of microscopic particles, the momentum exchange between the particle and the gas flow deviates from the standard macroscopic particle case. To account for slip flow, the no-slip conditions at the particle surface need to be modified using the Maxwell's slip model. A novel specific slip length model is proposed to allow for a continuous transition from the no-slip to slip flow regimes for various Knudsen number conditions.
THEORETICAL AND COMPUTATIONAL FLUID DYNAMICS
(2022)
Article
Engineering, Electrical & Electronic
E. Sutinys, A. Dzedzickis, U. Samukaite-Bubniene, V Bucinskas
Summary: Recent progress in 'powdered composites' has led to promising applications in flexible tactile, pressure, and force sensors based on compressed metal oxide powder mass materials. This paper evaluates the resistance of force-sensitive material - synthetic iron (III) oxide powder - by incorporating it into the design of two force sensors. Experimental results show that the synthetic iron (III) oxide powder composite has potential as a sensitive material for force and pressure sensors, offering high mechanical resistance and the ability to operate at high temperatures.
SENSORS AND ACTUATORS A-PHYSICAL
(2021)
Article
Engineering, Environmental
Qian Wang, Chiqian Zhang, Haesung Jung, Pan Liu, Dhara Patel, Spyros G. Pavlostathis, Yuanzhi Tang
Summary: Anaerobic digestion combined with hydrothermal treatment is an attractive technology for sewage sludge treatment and resource recovery. The study systematically characterizes the transformation of important heavy metals in sewage sludge during AD with pre- or interstage HT. Results show that both Cu and Zn predominantly occur as sulfides in HT hydrochars, with subsequent AD favoring the formation of specific metal species. These findings have important implications for understanding the fate and mobility of heavy metals in sludge-derived hydrochars and AD solids.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Editorial Material
Public, Environmental & Occupational Health
Seong Chan Kim, Dong-Bin Kwak, Thomas Kuehn, David Y. H. Pui
INFECTION CONTROL AND HOSPITAL EPIDEMIOLOGY
(2021)
Article
Thermodynamics
Dong-Bin Kwak, Seong Chan Kim, Handol Lee, David Y. H. Pui
Summary: This study analyzed the fluid flow characteristics on a sharp-bent tube under different conditions and conducted numerical simulations to analyze particle deposition patterns. It was found that most nanoparticles were deposited on the outer wall right after the bending point in the sharp-bent tube, and the differences in relative deposition efficiency along the azimuthal angles were reduced as Reynolds number increased.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Chemistry, Multidisciplinary
Qian Wang, Xiaoguang Liu, Haesung Jung, Simin Zhao, Spyros G. Pavlostathis, Yuanzhi Tang
Summary: This study investigated the evolution and mineralization of P and N in sewage sludge during AD with prestage HT, revealing that the formation of struvite or vivianite in the final AD solids is highly dependent on the Mg/Fe molar ratio and/or the pH of AD suspensions. Additionally, both HT and AD strongly affected N speciation evolution in sewage sludge.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Qian Wang, Haesung Jung, Biao Wan, Pan Liu, Peng Yang, Yuanzhi Tang
Summary: Hydrothermal treatment (HT) is an emerging technique for sustainable sewage sludge management and resource recovery, with a focus on the dynamic speciation evolution of phosphorus (P) and nitrogen (N) during the process. The study provides new insights into the transformation of P and N during HT of Fe-rich sludges as well as a modular design for maximum P and N recovery from the treatment products.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Haesung Jung, Colin Snyder, Wenqian Xu, Ke Wen, Mengqiang Zhu, Yan Li, Anhuai Lu, Yuanzhi Tang
Summary: The study demonstrates rapid photocatalytic oxidation of Mn2+(aq) under circumneutral conditions catalyzed by naturally abundant semiconducting TiO2 minerals. The photocatalytic oxidation rates are comparable to or even higher than those of reported biotic/abiotic processes. Additionally, the rapid photocatalytic oxidation leads to the formation of large tunnel structured Mn oxides on the surface of TiO2, suggesting a previously overlooked pathway for understanding the occurrence of natural Mn oxide coatings on rock surfaces.
ACS EARTH AND SPACE CHEMISTRY
(2021)
Article
Engineering, Chemical
Feng Jia, Wei Huang, David Y. H. Pui, Chuen-Jinn Tsai
Summary: This paper extends the classical theory for diffusional loss of aerosol particles in fully developed laminar flow through a circular tube by considering the slip-flow condition in gas flow at low pressure or with small characteristic length scale. The solution involves the separation of variables, use of confluent hypergeometric function, evaluation of eigenvalues for Knudsen numbers, and development of a power series correlation to describe aerosol penetration in the slip flow regime. In this regime, penetration decreases with increasing Knudsen number, with the solution showing good agreement with previous studies.
JOURNAL OF AEROSOL SCIENCE
(2022)
Article
Engineering, Chemical
Thi-Cuc Le, Chun-Hsuan Lin, Wen-Cheng Gong, Vladimir Zdimal, David Y. H. Pui, Chuen-Jinn Tsai
Summary: In this study, a nanoparticle inertial classifier (NIC) was developed for nanoparticle classification at high particle mass loading conditions with low pressure drop and good classification performance. The NIC can be used for applications such as nanopowder classification or inhalation toxicity testing efficiently.
JOURNAL OF AEROSOL SCIENCE
(2022)
Article
Engineering, Chemical
Weiqi Chen, Qisheng Ou, Cheng Chang, Chenxing Pei, Xin Liu, Matti Maricq, David Kittelson, David Y. H. Pui
Summary: This paper investigates the use of artificial aerosols to synthesize nano-scale membranes that mimic the soot cake in diesel particulate filters (DPF) for gasoline direct injection (GDI) engines. The experiments demonstrate that membranes produced with larger aggregate size particles or under lower face velocity yield better performance in terms of filtration efficiency and pressure drop.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Engineering, Biomedical
Linsey Griffin, Minji Yu, Alison Cloet, Susan Arnold, Neil Carlson, Marc Hillmyer, Qisheng Ou, Chenxing Pei, Qingfeng Cao, David Pui, Rhonda Franklin, William Durfee
Summary: The research aimed to develop and test alternative N95 respirators that could be produced domestically to address the shortage of traditional respirators. New mask designs were developed using repurposed filtration media and commercially available components, and were tested for filtration and fit performance. The tests demonstrated that the new mask designs can be viable alternatives to traditional N95 masks in terms of filtration efficiency and fit.
JOURNAL OF MEDICAL DEVICES-TRANSACTIONS OF THE ASME
(2022)
Article
Multidisciplinary Sciences
Yan Ye, David Y. H. Pui
Summary: Intentionally intensifying the light scattering of medium molecules allows the detection of suspended nanoparticles under conditions not suitable for conventional optical microscopies or laser particle counters. This method can distinguish between nanoparticles and microparticles, and directly detect suspended nanoparticles much smaller than visible light wavelengths.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Multidisciplinary
Yingshu Liu, Jiayu Zuo, Ziyi Li, Jun Li, Xiaoqin Zou, Xiong Yang, Bentao Yang, Chuanzhao Zhang, Haoyu Wang, David Y. H. Pui, Ralph T. Yang
Summary: This study proposes a membrane separation strategy using chabazite zeolite (SSZ-13) membranes to separate SO2 from NO2, and provides insights into the feasibility and advantages of this process using molecular simulation. The results show that SO2 has a strong competitive adsorption capacity, while NO2 is significantly reduced due to dimerization. Additionally, the study reveals the rapid transport of NO2 and the temperature dependence of SO2 diffusion on SSZ-13.
Article
Chemistry, Analytical
Yan Ye, Qisheng Ou, Weiqi Chen, Qingfeng Cao, Dong-Bin Kwak, Thomas Kuehn, David Y. H. Pui
Summary: A new method is proposed to detect airborne nanoparticles by detecting the light scattering caused by both the particle and the surrounding molecules. This method overcomes the limitations of conventional laser optical methods while maintaining simplicity and cost-effectiveness, paving the way for the further development of nanoparticle detection technology.
Article
Engineering, Chemical
Qiang Lyu, Qisheng Ou, Weiqi Chen, Yujun Wang, Cheng Chang, Yuejin Li, Defu Che, David Y. H. Pui
Summary: The study investigated the influence of catalyst coating on the filtration performance of silicon carbide (SiC) filter cores, finding that the coating significantly decreased the initial filtration efficiency and led to faster increases in filtration efficiency and pressure drop over time in the deep-bed filtration regime. Analysis revealed that the catalyst is preferentially deposited in smaller pores, reducing pore volume for relevant filtration pores, and wiping out a group of smaller pores. The study provides a working mechanism to explain the decreased filtration efficiency on catalyzed filters based on experimental and characterization data.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Engineering, Chemical
Zhengyuan Pan, Qisheng Ou, Francisco J. Romay, Weiqi Chen, Tianle You, Yun Liang, Jing Wang, David Y. H. Pui
Summary: The microstructure of filter media plays a crucial role in determining its macroscopic properties. This study investigated the dust loading process in structure-resolved filter media using microscale simulations. The results provide insights into the influence of structural factors on the dust holding capacity of the filter media and propose a strategy for designing innovative filters.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Engineering, Chemical
Francisco J. Higuera, Juan Fernandez de la Mora
Summary: This study investigates a particle condensation device that uses cold and warm humid air streams to achieve water vapor condensation. Compared to existing water condensation particle counters, this configuration offers advantages such as variable saturation ratio, accelerated penetration of water vapor, and a relatively uniform saturation field.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Brijal Prajapati, Vishal Dharaiya, Manoranjan Sahu, Chandra Venkatraman, Pratim Biswas, Kajal Yadav, Delwin Pullokaran, Ramya Sunder Raman, Ruqia Bhat, Tanveer Ahmad Najar, Arshid Jehangir
Summary: This study evaluated the performance of a low-cost particulate matter sensor and proposed a physics-based calibration method. The results showed that the physics-based calibration approach performed better compared to statistical models at both observation sites.
JOURNAL OF AEROSOL SCIENCE
(2024)
Correction
Engineering, Chemical
N. Searle, K. Kaur, K. Kelly
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Tianyu Cen, Laura Torrent, Andrea Testino, Christian Ludwig
Summary: In this study, a hyphenated setup consisting of a rotating disk diluter (RDD) with spICP-MS (RDDspICP-MS) was used for online sampling and characterization of metallic nanoparticles (NPs) in ambient pressure aerosols. The RDD allowed for constant flow rate sampling of aerosols and adjusting the dilution ratio for different particle number concentrations (PNCs). The feasibility of this setup was tested with different sizes of AuNPs in argon-based and air-based aerosols, and the results showed a lower limit of detection for number concentration. The capability of the setup to accurately investigate multi-modal samples and the interference of ionic species was also demonstrated.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
A. Valenzuela, E. Bazo, R. A. Rica, L. Alados-Arboledas, F. J. Olmo-Reyes
Summary: This article introduces a method to measure the extinction cross section of levitated particles using an electrodynamic trap and double-cavity ring down spectroscopy technique, and demonstrates the potential of this method in 1,2,6-hexanetriol particles through simulations and experiments. Unlike traditional methods, this technique provides crucial information about the extinction cross section of sodium chloride particles during dehydration and hydration processes.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Shadi Yaqoubi, Mohaddese Sokuti, Sahand Mazloum-Ravasan, Kofi Asare-Addo, Hamed Hamishehkar, Ali Nokhodchi
Summary: In this study, a modified version of ultrasonic spray pyrolysis was used to prepare salbutamol sulfate dry powder. The engineered particles showed suitable characteristics for effective drug delivery to the lungs and demonstrated acceptable aerosolization performance. This newly introduced method appears to be capable of producing dry powder formulations of different drugs without the need for surfactants or stabilizers.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Ashley L. Nord, Patrice Dosset, Pierre Slangen, Manouk Abkarian
Summary: Phonation has been found to be a potent transmission route for the COVID-19 virus. To control transmission, it is important to measure the amount of aerosols produced by speech. Researchers used digital in-line holography to overcome experimental challenges and successfully imaged the formation and deformation of saliva filaments in the mouth during speech, as well as the resulting aerosolized droplets.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Yating Wang, Yiyang Zhang, Zhu Fang, Xinxin Wu
Summary: The research investigates the energy dissipation in particle-wall collision with roughness using the finite element method. The results show that the presence of surface roughness leads to lower viscoelastic dissipation and higher restitution coefficient compared to a smooth surface. The collision time is identified as a key factor in predicting the energy dissipation.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Shaamrit Balendra, Akshay Kale, Julie Pongetti, Mohsen Kazemimanesh, Molly Haugen, Lee Weller, Adam Boies
Summary: The measurement of airborne particles is important for detecting and characterising air pollution, emissions, fire detection, occupational and climate impacts. However, current optical particle counters (OPCs) cannot measure ultrafine particles. This study explores the limitations of miniaturising a condensation particle counter (CPC) growth chamber and provides a toolkit for optimising the design of miniaturised CPC-GCs.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Markus Snellman, Namsoon Eom, Maria E. Messing, Knut Deppert, Chris Hogan
Summary: Segregated bimetallic nanoparticles, such as core-shell nanoparticles, have attracted widespread interest in various fields like biomedicine, catalysis, and optoelectronics. Aerosol technology provides an optimal platform for controlling the size, structure, and composition of nanoparticles, which are crucial parameters for tuning the material performance for specific applications. In this study, researchers developed a novel evaporator design that allows on-line coating of core particles with a shell directly in the gas phase. By utilizing a local heater, the researchers were able to decouple the heating process of the evaporating material from the aerosol particles, thereby limiting core-shell alloying. The resulting core-shell particle formation with controllable shell thickness was demonstrated using evaporation of zinc onto core particles of gold, tin, and bismuth. Simple models were also discussed to explain the observed growth process inside the evaporator and the formation of the shell.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Kentaro Misawa, Yuto Kasai
Summary: In this study, the laser-induced fluorescence technique was used to observe scattered and fluorescent signals from fluorescent polystyrene latex particles. The ratio of fluorescence to scattered signal intensities was found to be almost equal for particles of the same size, allowing for the separate observation of mixed-size fluorescent particles. Relative fluorescence intensities were obtained by incorporating ratios of fluorescence to scattered signal and relative scattered signal intensities.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Sripriya Nannu Shankar, William B. Vass, John A. Lednicky, Tracey Logan, Rebeccah L. Messcher, Arantzazu Eiguren-Fernandez, Stavros Amanatidis, Tara Sabo-Attwood, Chang-Yu Wu
Summary: This study introduces a testing system that allows for direct exposure of aerosolized viruses onto host cells. By collecting particles of different sizes and analyzing them, researchers obtained information on the concentration and viability of the virus at different particle sizes.
JOURNAL OF AEROSOL SCIENCE
(2024)
