Article
Engineering, Chemical
Humair Nadeem, Shankar Subramaniam, Nandkishor K. Nere, Theodore J. Heindel
Summary: A novel particle neighborhood based mixing index, called the generalized nearest neighbor (GNN) mixing index, is developed to measure solids mixing at the particle scale. The GNN index is statistically robust and grid-independent, providing reliable particle scale mixture homogeneity values. It can be adapted to mixtures of unequal proportions or mixtures containing more than two species.
ADVANCED POWDER TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Ali Rahimzadeh, Farhad Ein-Mozaffari, Ali Lohi
Summary: This study investigates the effects of aeration rate, impeller type, rotating mode, impeller speed, and pumping direction on gas dispersion efficacy in aerated coaxial mixers containing non-Newtonian fluids. The results suggest that maintaining a constant aeration rate per volume of the non-Newtonian fluid is beneficial for preserving the performance of large-scale coaxial mixers. The use of specific power consumption as a scale-up criterion improves the energy dissipation rate uniformity critical for shear-sensitive applications.
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2022)
Article
Chemistry, Analytical
Keyi Nan, Yanxia Shi, Tianyun Zhao, Xiaowei Tang, Yueqiang Zhu, Kaige Wang, Jintao Bai, Wei Zhao
Summary: This study investigated the effects of electric field intensity, AC frequency, electric conductivity ratio, and channel width at the entrance on the mixing effect of a Y-type electrokinetic turbulent micromixer. It was found that the optimal mixing can be achieved in a 350 μm wide micromixer under specific conditions.
ANALYTICAL CHEMISTRY
(2022)
Article
Construction & Building Technology
Yaxin Tao, A. V. Rahul, Manu K. Mohan, Kim Van Tittelboom, Yong Yuan, Geert De Schutter
Summary: This study investigates the blending performance of a helical static mixer used for twin-pipe 3D concrete printing. A linear relationship between mechanical strength and mixing homogeneity was established, and it was observed that a higher number of mixing elements led to a more dense pore structure.
CEMENT & CONCRETE COMPOSITES
(2022)
Article
Engineering, Electrical & Electronic
Chao-Ming Lin, Yu-Wen Chang
Summary: The study employed the Taguchi design methodology to optimize four geometry parameters of the passive mixer, evaluating the temperature distribution at the mixer outlet through Moldex3D simulations. The results showed that the optimal parameter settings led to significant improvements in temperature uniformity and mixing index.
MICROSYSTEM TECHNOLOGIES-MICRO-AND NANOSYSTEMS-INFORMATION STORAGE AND PROCESSING SYSTEMS
(2021)
Article
Computer Science, Interdisciplinary Applications
Youngwoo Kim, Omid Nematollahi, Hyun Dong Kim, Kyung Chun Kim
Summary: In this study, the mixing characteristics of a multilayer static mixer were investigated using PLIF, showing that the arrangement angles do not affect the mixing index at higher flow ratios but significantly impact the mixing performance at lower flow ratios, with 45 degrees resulting in the highest mixing index and lowest friction factor.
JOURNAL OF VISUALIZATION
(2021)
Article
Energy & Fuels
Ana M. Diaz, Ines Terrones-Fernandez, Pedro Javier Gamez-Montero, Robert Castilla
Summary: In microbiology laboratories, it is crucial to obtain high-quality homogeneous samples for culture media. The pour plate method involves melting and seeding the culture media, which consist of agar and nutrient solution. To validate a CFD model and provide insights into mixer design, a static mixer was designed using Computational Fluid Dynamics (CFD) and OpenFOAM software. By comparing the CFD model with literature, it was found that the internal mixer achieved better performance in achieving homogeneous mixing for fluids with high viscosity ratio. However, the external mixer was easier to manufacture but more computationally complex.
Article
Engineering, Chemical
Sean Noble, Michael Poirier, John Thomas
Summary: This paper presents a numerical approach based on the lattice Boltzmann method for predicting the time-accurate fluid flow and mixing properties of non-Newtonian fluids. The approach is able to characterize the blending in shear-thinning fluids and cavern formation in yield-stress fluids. The simulations show good agreement with measured data and first-principles theory, and do not require reparameterization or retuning between scenarios, demonstrating its generality. The approach is also applied to modeling a nuclear waste processing unit operation.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Chemical
Ziqi Li, Guina Yi, Ziqi Cai, Zhengming Gao
Summary: In this study, the behavior of two non-Newtonian droplets during their impingement and mixing on a solid surface was investigated using the Many Body Dissipative Particle Dynamics method. The relationship between droplet morphology and the Weber number of the impinging droplet was studied, and the mixing process was divided into two stages dominated by convection and molecular diffusion, respectively. The study also revealed a special phenomenon in the mixing process caused by the difference in particle diffusion coefficients.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Chemical
Xingren Jiang, Ning Yang, Rijie Wang
Summary: Continuous manufacturing in the pharmaceutical industry has gained more attention due to its safety features and improved mass transfer, but scalability has been a challenge. The Kenics static mixer in a tubular flow reactor has emerged as a solution for this issue, with research indicating that a lower aspect ratio can lead to better mixing performance. Adjusting the aspect ratio of the Kenics static mixer could be a new strategy for scaling up continuous processes in pharmaceutical production.
Article
Engineering, Chemical
Aditya R. Pujari, Sarvgya Kumar, Pradeep Kumar Sow
Summary: Inspired by the unique behavior of the turritella seashell, this study demonstrates that a similar geometry can be used as an effective static mixer insert for inline mixing in a pipe. By parameterizing the geometry and conducting CFD studies, a two-step mixing mechanism is proposed and its performance is evaluated under different conditions. It is found that the inlet velocity, pipe diameter, surface boundary conditions, and insert geometry parameters can all affect the mixing output. Additionally, the no-slip boundary condition is crucial for creating shearing in the fluid, and the insert geometry can be optimized to minimize pressure drop.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Thermodynamics
Seon Yeop Jung, Jo Eun Park, Tae Gon Kang, Jun Dong Park
Summary: This study numerically investigates the flow and mixing characteristics of a thixotropic fluid in a static mixer. The results show that the characteristics of the thixotropic fluid are influenced by the flow parameters and the thixotropy parameter. As the flow parameters increase, the mixing characteristics become more complex, and the thixotropy parameter significantly affects the average of the structure parameter. From the analysis of the Poincare section and the flux-weighted intensity of segregation, it is found that the mixing performance improves with the increase of the thixotropy parameter in the counter-rotational static mixer, while a more complex trend of the degree of mixing is observed in the co-rotational mixer.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Engineering, Chemical
Angga Pratama Herman, Jieqing Gan, Zongyan Zhou, Aibing Yu
Summary: This work presents a numerical study on particle mixing and scale-up of ribbon mixers with different sizes. The study found that as the mixer size increases, the mixing performance worsens. A correlation is proposed to predict the mixing rate based on the scale-up ratio and Froude number. It was observed that the top-bottom loading condition leads to faster mixing compared to the side-side and front-back loading conditions. Additionally, the total mixing time increases significantly with larger mixer sizes. The power consumption per unit mass follows a specific order among the four mixers. The study suggests that scale-up is necessary to save time and power consumption, as well as reduce operating costs.
Article
Biotechnology & Applied Microbiology
M. Constanza Sadino-Riquelme, Jose Rivas, David Jeison, Andres Donoso-Bravo, Robert E. Hayes
Summary: This study investigates the interaction between broth rheology and impeller mixing in fermentation processes. The increase in alginate concentration leads to enhanced pseudoplasticity of the broth, resulting in impaired mixing. Experimental and computational fluid dynamics methods are used to analyze the impact on fluid flow patterns and impeller torque measurements.
FERMENTATION-BASEL
(2022)
Article
Nuclear Science & Technology
Weicong Zhu, Dongyang Li, Mingpeng Chen, Guanhui Xie, Sichao Tan, Ruifeng Tian
Summary: This article investigates the flow mixing characteristics of coolants and the distribution of boron concentration in reactor pressure vessels. It was found that localized eddy currents led to the formation of high concentration retention zones and V-shaped boron concentration distribution in the core. The best mixing diffusion behavior of boron concentration was observed at a certain ratio.
ANNALS OF NUCLEAR ENERGY
(2024)
Review
Chemistry, Physical
Nina M. Kovalchuk, Mark J. H. Simmons
Summary: Surfactants are used in microfluidic systems to stabilize drops and study phenomena in industrial processes. The dynamics of surfactants play a crucial role in drop formation, movement in channels, coalescence, and surfactant adsorption. This review discusses the effects of surfactant dynamics on microfluidic operations and the advantages and challenges of measuring dynamic interfacial tension using microfluidics.
ADVANCES IN COLLOID AND INTERFACE SCIENCE
(2023)
Article
Engineering, Chemical
Giuseppe Forte, Matteo Antonelli, Elisabetta Brunazzi, Mark J. Simmons, Hugh Stitt, Federico Alberini
Summary: This study successfully identifies different gas-liquid flow regimes using a passive acoustic emission process sensor and machine learning methods. The pressure fluctuations (acoustic emissions) in an air-water system were recorded to detect various flow states. The optimal features were selected and three different machine learning algorithms were trained, achieving accurate predictions of the gas-liquid flow regimes of interest.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Engineering, Chemical
Daniel Ingo Hefft, Federico Alberini
Summary: Alberini et al. have developed a new technology using a single sensor to provide real-time measurement of rheology. Analysis of the transient energy released during probe-fluid interaction identified distinct acoustic fingerprints in the frequency domain, which are characteristic of different fluids and their rheology. The study also demonstrated a direct correlation between acoustic emissions and flow rate using a neural network regression test.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Engineering, Chemical
Francesco Maluta, Federico Alberini, Alessandro Paglianti, Giuseppina Montante
Summary: In this work, the authors present original data on bubble size distribution in a gas-liquid stirred tank obtained through a combination of experimental and computational methods. The aim is to contribute to the development of fully predictive methods for the design and scale-up of chemical and biochemical gas-liquid reactors. The paper discusses the variables that affect mass transfer in industrial aerobic fermentations, with a special focus on bubble size distribution, gassed power consumption, and gas cavities. The latest developments of Two Fluid and Population Balance models for obtaining fully predictive results on gas-liquid mixing in stirred tanks are also discussed. The results highlight the importance of accurately predicting bubble size in the impeller zone for reliable hydrodynamics results in aerated stirred tanks.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2023)
Article
Engineering, Chemical
Zechen Yao, Federico Alberini, Giuseppina Montante, Alessandro Paglianti
Summary: This work focuses on the experimental analysis of a tubular reactor equipped with Kenics static mixers under turbulent flow conditions, aiming to demonstrate the advantages of in-line monitoring tools for continuous process applications. Electrical Resistance Tomography, pressure transducers, and Particle Image Velocimetry are used to evaluate the mixing performance, pressure drop, and flow field. The study shows the applicability of Electrical Resistance Tomography in offering insight into continuous reactors and the potential of monitoring the mixing performance inside the static mixers. The experimental data suggests alternative configurations for optimizing the fluid mixing process.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2023)
Article
Engineering, Chemical
Konstantia Nathanael, Sibo Cheng, Nina M. Kovalchuk, Rossella Arcucci, Mark J. H. Simmons
Summary: The synthesis of silver nanoparticles (AgNPs) is optimized using a T-junction microfluidic system and a machine learning approach. The reduction of silver nitrate with tannic acid in the presence of trisodium citrate is used to synthesize AgNPs. The study uses a decision tree-guided design of experiment method to determine the size of AgNPs.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2023)
Article
Engineering, Chemical
M. G. Romano, F. Alberini, L. Liu, M. J. H. Simmons, E. H. Stitt
Summary: This study simulated Newtonian and non-Newtonian fluid flows in a vessel stirred with a Rushton turbine using CFD. The results were compared to 3D-PTV measurements. For Newtonian fluids, the turbulence models predicted similar mean flow and matched experimental velocity data well. The standard k-e model showed the closest power number to expected values and resolved a significant portion of the total energy dissipation. However, simulations of non-Newtonian flows presented challenges in reproducing the measured flow patterns and predicting mean velocity accurately. Nonetheless, the predictions for yield stress fluids were reasonably consistent with experimental observations.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Mechanical
Z. Yao, F. Alberini, G. Montante, A. Paglianti
Summary: In this study, a off-axis 2D Particle Image Velocimetry system was used to obtain the 3D flow field at the outlet of a tubular reactor with Kenics static mixers. The symmetrical features of the flow generated by the static mixers were considered and the out-of-plane velocity component was exploited to obtain the 3D flow fields. The methodology was validated by comparing the results with a symmetrical 2D-PIV system in a smaller reactor.
EXPERIMENTAL TECHNIQUES
(2023)
Article
Engineering, Mechanical
Jake Airey, James Simpson, Matthew Spencer, Richard W. Greenwood, Mark J. H. Simmons
Summary: This article explores the impact of anti-wear additives on micropitting and tribofilm formation. The study finds that aviation anti-wear additives promote micropitting less than zinc dialkyldithiophosphate (ZDDP) but more than base oil alone. The slower formation of tribofilms allows for initial running-in of surfaces, effectively delaying the initiation of micropitting.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2023)
Article
Pharmacology & Pharmacy
Konstantinos Stamatopoulos, Connor O'Farrell, Mark J. H. Simmons, Hannah K. Batchelor, Nena Mistry
Summary: A physiologically based biopharmaceutic model (PBBM) was developed to predict the pharmacokinetic (PK) data of theophylline based on dissolution profiles measured in the Dynamic Colon Model (DCM). The DCM showed superior predictions compared to the United States Pharmacopeia (USP) Apparatus II (USP II) for the 200 mg tablet. However, erosion of the tablet in the USP II resulted in overpredicted PK data. The DCM was recommended for dosage forms with distal gastrointestinal (GI) tract release phenomena.
Article
Engineering, Chemical
S. D. Hare, D. Werner, C. R. K. Windows-Yule, T. Z. Kokalova Wheldon, E. Kendrick, M. J. H. Simmons
Summary: The mixing of electrode slurries is essential in lithium-ion battery manufacturing and can significantly impact the battery's performance. This study used Positron Emission Particle Tracking (PEPT) to analyze the fluid dynamics and dispersion of a graphite-based anode slurry in a specific mixer. The research focused on wetting graphite particles and breaking up large agglomerates, observing different mixing dynamics at various rotor speeds.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2023)
Article
Chemistry, Physical
Kewei Zhu, Sibo Cheng, Nina Kovalchuk, Mark Simmons, Yi-Ke Guo, Omar K. Matar, Rossella Arcucci
Summary: In this study, the use of deep learning generative models is proposed to predict drop coalescence in chemical engineering. By training the predictive models with generated synthetic data, the lack of training data and label imbalance problem can be overcome. A novel generative model called DSCVAE is developed for labelled tabular data, which is capable of generating consistent and realistic samples compared to the standard CVAE. By enhancing random forest and gradient boosting classifiers on synthetic data and evaluating their performances based on real experimental data, numerical results show a considerable improvement in prediction accuracy, with DSCVAE outperforming the standard CVAE. This research provides valuable insights into handling imbalanced data for classification problems, particularly in chemical engineering.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Engineering, Chemical
Grace E. Cunningham, Shreyasi Deshpande, Mark J. H. Simmons, Jonathan O'Sullivan
Summary: This study explores the use of traditional mixer-viscometer techniques to infer viscosity from torque-speed data during batch mixing processes. The non-linearity in torque-speed data at lower fill levels presents challenges, which may require non-linear modelling techniques or data driven models to overcome.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Environmental
Paula Pico, Konstantia Nathanael, Alessio D. Lavino, Nina M. Kovalchuk, Mark J. H. Simmons, Omar K. Matar
Summary: In this study, the production of silver nanoparticles under different operating conditions was investigated using a combination of population balance modelling and computational fluid dynamics. The results showed that the process parameters have an impact on the size and distribution of the nanoparticles.
CHEMICAL ENGINEERING JOURNAL
(2023)
