Article
Engineering, Chemical
Jiazhong Zhou, Bo Sun, Shankar Subramaniam
Summary: The flow past disperse solid particles or bubbles in a carrier fluid induces fluctuations in fluid velocity and temperature, resulting in a pseudo-turbulent heat flux (PTHF). The transport of PTHF is important for energy budget in two-fluid models, and it is modeled using a pseudo-turbulent thermal diffusivity (PTTD). However, the original PTTD correlation becomes unrealistic at low solid volume fractions. In this study, additional data is reported and improved correlations are developed to better predict PTHF transport in dilute flows.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Thermodynamics
Muhammed A. Hassan, Amro H. Al-Tohamy, Amr Kaood
Summary: This study aims to achieve balanced hydrothermal performance by investigating the number and shape of holes in conical rings. The results show that solid divergent rings can achieve higher Nusselt numbers, but also have higher friction factors. Perforating the rings reduces both Nusselt number and friction factor for more balanced performances.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2022)
Article
Engineering, Manufacturing
Tom Van Waeleghem, Flavio H. Marchesini, Ludwig Cardon, Dagmar R. D'hooge
Summary: Fused filament fabrication (FFF) is widely used for polymeric materials. However, the quality of final printed parts is suboptimal due to voids and incomplete bond formation. A computational study was conducted to analyze temperature gradients and void formation during the deposition process. The study demonstrated a dynamic heat transfer, renewing interlayer contact and allowing for tuning of renewable welding.
ADDITIVE MANUFACTURING
(2023)
Article
Mechanics
Zhentong Zhang, Dominique Legendre, Remi Zamansky
Summary: This paper studies the effects of finite particle Reynolds numbers on the dynamics of small spherical bubbles and solid particles in isotropic turbulent flow. Through direct numerical simulations, it is shown that a satisfactory prediction of these quantities can be provided using Tchen's theory, specifying conditions under which the total inertial force is negligible compared to the drag force. The study also highlights the potentially significant role of added mass and fluid inertia forces for large Stokes numbers.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Chemistry, Applied
Cheng Cheng, Guannan Wang, Xi Huang, Xiaobing Zhang
Summary: This paper investigates the influence of gunshot residue particles on muzzle flow during the firing of guns. Using a two-dimensional gas-solid two-phase model and a discrete phase model, the different development processes between pure gas and gas-solid flow are discussed, and the effects of particle diameter and mass fraction on the development process of muzzle flow are explored.
PROPELLANTS EXPLOSIVES PYROTECHNICS
(2023)
Article
Thermodynamics
Joo Hyun Moon, Soyeong Lee, Jungho Lee, Seong Hyuk Lee
Summary: This study numerically investigates the rapid cooling heat transfer characteristics of superheated solid surfaces when subjected to subcooled water jet impingement. The results show the formation of a vapor blanket near the impingement point, preventing direct contact between the liquid and heated surface.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Engineering, Chemical
Zeyu Li, Zhenbo Tong, Aibing Yu, Hao Miao, Kaiwei Chu, Hao Zhang, Gang Guo, Jiang Chen
Summary: Hydrogen utilization is gaining attention and the supercritical water circulating fluidized bed reactor can generate hydrogen. This study uses CFD to analyze cyclone separation mechanisms under supercritical fluid, finding that changing the content of carbon dioxide and adding extra dipleg can improve cyclone performance.
Article
Thermodynamics
Saeed Farsad, Mahmoud Mashayekhi, Mohammad Hossein Zolfagharnasab, Mohammad Lakhi, Foad Farhani, Kourosh Zareinia, Vahab Okati
Summary: This study evaluates the thermofluidic performance of Dimpled-Protruded tubes through four novel investigations. The results show that small vorticities at the Dimpled-Protruded locations increase the interfacial heat transfer, rough tubes enhance heat transfer, and Dimpled-Protruded tubes effectively improve forced-convecting heat transfer.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Engineering, Mechanical
Diego R. Rivera, Nelson O. Moraga
Summary: This study investigates the combined effects of turbulent mixed heat convection and surface thermal radiation on heat transfer and exergy destruction in a cavity with a heat-conducting square solid at its center. The results show that turbulence and thermal radiation significantly affect velocity, temperature, and exergy destruction, while the variation of the thermal diffusivity ratio has a smaller impact.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Engineering, Aerospace
Yilang Liu, Weiwei Zhang, Zhenhua Xia
Summary: This paper proposes a new data assimilation method, called Proper Orthogonal Decomposition Inversion (POD-Inversion), for recovering the high-fidelity turbulent mean flow field around an airfoil at high Reynolds numbers based on experimental data. The proposed method can reconstruct the high-fidelity mean flow field combined with experimental force coefficients and significantly reduce the dimensions of the system. The effectiveness of the method is verified by transonic flow and separated flow cases, demonstrating its ability to recover turbulent flow fields that optimally match the experimental data and reduce the error of aerodynamic coefficients. Furthermore, the proposed method can provide high-fidelity mean field data for establishing turbulence models based on machine learning.
AEROSPACE SCIENCE AND TECHNOLOGY
(2022)
Article
Thermodynamics
Jiahao Luo, Yu Rao, Li Yang, Mingyang Yang, Hang Su
Summary: Detailed computational analysis was conducted to study the flow and heat transfer features in a latticework structure under various flow configurations. It was found that different flow configurations significantly impact heat transfer, pressure loss, and flow structure features in the latticework subchannels. Specifically, the RFC latticework showed the highest heat transfer performance and pressure losses, while the CFC and TFC latticework had lower heat transfer performance with reduced pressure loss.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Thermodynamics
Paolo Caccavale, Benedetto Mele, Maria Valeria De Bonis, Gianpaolo Ruocco
Summary: In vehicle aerodynamics, new integrated systems based on shape memory metal alloys can be developed to create appendices that change shape in response to thermal inputs, improving vehicle performance and fuel consumption rate.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Engineering, Chemical
Zeyu Li, Zhenbo Tong, Hao Zhang, Kaiwei Chu, Renjie Li, Hao Miao, Jiansong Zhao, Aibing Yu
Summary: With the increasing energy demand and environmental pollution, the utilization of hydrogen energy is gaining attention due to its high calorific value and environmentally friendly combustion products. This study investigates the behavior of solid particles in a cyclone under the extreme conditions of supercritical water (SCW) by using a combined discrete element method (DEM) and computational fluid dynamics (CFD) model. The results show that particles significantly impact the flow fields and the interaction forces between particle and wall are smaller than particle-particle interactions. The findings contribute to the understanding of SCW-cyclone mechanism and can be helpful for optimizing cyclone performance.
Article
Thermodynamics
Aihong Zou, Fangqiu Yu, Ke Li, Wei Dai
Summary: The performance of a twin-tube convective switch is studied, and it is found that the geometric parameters and structures have significant impact on its performance. The performance of a heat switch with a vertical fin structure is further investigated, and it is found that its heat flow is higher than that of the experimental case with a cylindrical cavity.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Engineering, Chemical
Barlev R. Nagawkar, Venkata P. Kotrike, Alberto Passalacqua, Shankar Subramaniam
Summary: A mixing index based on solid volume fraction fields is developed for gas-solid flows. The performance of the new mixing index is tested in two applications, and methods for performance improvement are presented.
Article
Thermodynamics
A. D. Ilgun, A. Passalacqua, R. O. Fox
Summary: Two solution algorithms were developed for conditional moment closure using quadrature-based moment methods, aiming to eliminate the need for additional grid. Both algorithms were tested for multi-step H 2 combustion and achieved expected results with at most six quadrature nodes. The proposed algorithms ensure constant scalar mean during molecular mixing, providing accurate, cost-effective, and direct alternatives to traditional CMC solution methods.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Engineering, Environmental
A. D. Ilgun, R. O. Fox, A. Passalacqua
Summary: The semi-analytical solution for conditional moment closure (SA-CMC) eliminates additional conditioning-space discretization in CMC applications by assuming mixture-fraction PDF is represented by a beta-PDF. A novel quadrature-based moment method (QBMM-CMC) is developed for CMC applications, which does not assume the form of the mixture-fraction PDF. By solving closed forms for micromixing terms from CMC, exact expressions for mixture-fraction moments of any order are obtained.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Chemical
Zhizhong Ding, Shashank S. Tiwari, Chenguang Zhang, Mayank Tyagi, Bo Kong, Krishnaswamy Nandakumar, Jyeshtharaj B. Joshi
Summary: This study investigates the dynamic response of a neutrally buoyant elliptical cylinder in shear flow, revealing two distinct responses and discussing the transition between them through the prediction of a critical Reynolds number. The findings validate the effectiveness of the SDFIBM method for particles subjected to shear flows.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Engineering, Chemical
Barlev R. Nagawkar, Venkata P. Kotrike, Alberto Passalacqua, Shankar Subramaniam
Summary: A mixing index based on solid volume fraction fields is developed for gas-solid flows. The performance of the new mixing index is tested in two applications, and methods for performance improvement are presented.
Article
Engineering, Chemical
Shashank S. Tiwari, Swapnil Ghatage, Jyeshtharaj Joshi, Bo Kong
Summary: Multifluid model simulations are important for liquid-solid fluidized beds. Particle-particle interactions play a crucial role and closure models designed for gas-solid flow regimes are not suitable. Direct numerical simulations are needed to develop rational closure terms. A flow regime map is proposed as a guideline.
Article
Mathematics, Applied
Rodney O. Fox, Frederique Laurent
Summary: A tractable solution is proposed to a classical problem in kinetic theory by introducing the Hyperbolic Quadrature Method of Moments (HyQMOM) to close even-order moments, strictly based on properties of monic orthogonal polynomials. The method is shown to converge with increasing order, demonstrating efficiency and accuracy in closure of moment equations.
SIAM JOURNAL ON APPLIED MATHEMATICS
(2022)
Article
Mechanics
Krishnamurthy Ravichandar, R. Dennis Vigil, Rodney O. Fox, Stephanie Nachtigall, Andreas Daiss, Michal Vonka, Michael G. Olsen
Summary: Droplet dispersion in liquid-liquid systems is a crucial step in various industries. This study investigates droplet breakup using a novel method and finds that breakage time and breakage probability increase with increasing parent droplet size, while the shape of the child drop size distribution depends on the size of the parent droplet.
Article
Thermodynamics
Viraj V. Belekar, Nandkishor K. Nere, Kushal Sinha, Alberto Passalacqua, Theodore J. Heindel, Shankar Subramaniam
Summary: Thermal drying of granular mixtures is common in industrial operations. This study presents a mixture model for estimating the time required to heat the system for solvent vaporization and provides an analytical solution for verification. Additionally, a separated-phase heat transfer model is developed to account for the effect of heat transfer on the heating time of wet granular mixtures.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Computer Science, Interdisciplinary Applications
Kendrick Tan, Boshun Gao, Cheng-Hau Yang, Emily L. Johnson, Ming-Chen Hsu, Alberto Passalacqua, Adarsh Krishnamurthy, Baskar Ganapathysubramanian
Summary: This article presents a computational framework and study based on fluid simulations to evaluate the risk of airborne disease transmission in confined spaces. The study finds that wearing masks significantly reduces the transmission risk.
ENGINEERING WITH COMPUTERS
(2023)
Article
Engineering, Chemical
Rodney O. Fox, Frederique Laurent, Alberto Passalacqua
Summary: The quadrature method of moments (QMOM) is a method to close the moment source terms based on the properties of orthogonal polynomials. The generalized quadrature method of moments (GQMOM) extends QMOM by using recursion coefficients and provides a more accurate moment closure.
JOURNAL OF AEROSOL SCIENCE
(2023)
Article
Energy & Fuels
Antonio Soria-Verdugo, Eduardo Cano-Pleite, Alberto Passalacqua, Rodney O. Fox
Summary: The effect of biomass particle shape on the conversion of beech wood during pyrolysis in a bubbling fluidized bed was investigated. The experimental results demonstrated that the pyrolysis velocity of the particles was proportional to their characteristic heat transfer length. The pyrolysis time ranged from 43 to 85 s at 500°C and from 27 to 53 s at 600°C.
Article
Engineering, Chemical
Shuaifeng Zhang, Zhuotai Jia, Bo Kong, Shaoping Ma, Zai-Sha Mao, Qinghua Zhang, Ning Yang, Chao Yang
Summary: A multiscale model of slurry-phase olefin polymerization is developed to account for the existence of gas-liquid mass transfer resistance. The comprehensive model integrates the reaction kinetic model, single particle model, and overall mass conservation balance. The interdependence of mass transfer resistance and polymerization reactions is evaluated. The model prediction is validated with literature data, and the effects of operating conditions on polymerization rate and polymer properties are discussed.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Mechanics
Palas Kumar Farsoiya, Zehua Liu, Andreas Daiss, Rodney O. Fox, Luc Deike
Summary: In this study, we investigate the morphology, occurrence, time, and size distribution of drop break-up in homogeneous isotropic turbulence through numerical simulations. The results show that the critical Weber number for drop break-up is nearly constant for viscosity ratio mu(r) <= 20, while it increases with mu(r) (and Reynolds number) for mu(r) > 20. The break-up time is delayed and is influenced by the distance to criticality. The first break-up child-size distribution transitions from M to U shape as the distance to criticality increases for mu(r) <= 20. The distribution shape is modified at high mu(r). At high We, a d(-3/2) size distribution is observed for mu(r) <= 20, while for mu(r) > 20, most of the drops formed by fragmentation are at the smallest scale, controlled by the diameter of the filament.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Victor Boniou, Rodney O. Fox
Summary: The main goal of this study is to explore the closures used in two-fluid models for representing interphase forces between particles and high-speed flows. By employing a hyperbolic two-fluid model, the interaction between an incident shock with Mach number M-s and a thin, moderately dense particle curtain is investigated. The two-fluid model is able to reproduce the experimental data, with some discrepancies observed in configurations with the smallest M-s. Furthermore, the study highlights the importance of investigating the particle-Mach number (M-p) dependence of drag and added-mass coefficients, which have not been extensively explored in the literature.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2023)
Article
Engineering, Chemical
Qing Han, Mengqing Shi, Linkai Han, Di Liu, Mingwei Tong, Yuxin Xie, Zhonghua Xiang
Summary: Developing highly efficient bifunctional oxygen electrocatalysts is crucial for zinc-air flow batteries. Metal-organic frameworks (MOFs) and covalent organic polymers (COPs) have emerged as promising alternatives due to their designable and controllable atomic-level structures. However, their catalytic performances are limited by conductivity and catalytic activity. In this study, nanosheet FeNi-MOF and iron phthalocyanine rich COP hybrid materials are assembled through the pi-pi stacking effect to create highly efficient bifunctional electrocatalysts. The resulting catalyst exhibits superior catalytic performance and stability, making it a promising candidate for zinc-air flow batteries.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Daria Grigorash, Dmytro Mihrin, Rene Wugt Larsen, Erling H. Stenby, Wei Yan
Summary: The article introduces a new approach to describe the cross-association between molecules, allowing for the simulation of weakly bound molecular complexes with different conformations in mixtures. By incorporating this approach into the equation of state, accurate predictions of vapor-liquid equilibrium and liquid-liquid equilibrium can be made. The new method is validated through experiments on alcohol and acid mixtures, with the results compared to experimental data, demonstrating its accuracy and reliability.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Mohammed Al-Sharabi, Daniel Markl, Vincenzino Vivacqua, Prince Bawuah, Natalie Maclean, Andrew P. E. York, Axel Zeitler
Summary: This study used terahertz pulsed imaging to investigate the transport process of different solvents into ceramic catalytic materials. The results showed that the heating rate of the samples influenced the water transport rate, while the viscosity of 1-octanol slowed down its transport.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Chukwunonso Anyaoku, Sati Bhattacharya, Rajarathinam Parthasarathy
Summary: This study aimed to enhance understanding of settling dynamics in viscoelastic fluids by developing a semi-empirical correlation and a dimensionless ratio, which accurately described the characteristics of settling suspensions.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Antti I. Koponen, Janika Viitala, Atsushi Tanaka, Baranivignesh Prakash, Olli-Ville Laukkanen, Ari Jasberg
Summary: This study focuses on the development of foam application chemicals for the paper and board industry. The research explores the rheology of the polyvinyl alcohol foam used in the process. Measurements were conducted to determine the foam viscosity and slip flow. The results suggest that slip flow contributes significantly to the total flow rate, and the obtained viscosity and slip models provide a solid foundation for industrial processes.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Dalei Sun, Jinghui Cai, Yating Yang, Zhiwu Liang
Summary: In this study, Fe-doped alpha-Bi2O3 catalysts with different Fe/Bi molar ratios were synthesized and utilized in the carbonylation of isobutyl amine with CO2. The results showed that Fe doping significantly enhanced the catalytic abilities of alpha-Bi2O3.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Yuan Tian, Xinxin Wang, Yanrong Liu, Wenping Hu
Summary: This paper predicts the solubility of nitrogen gas in ionic liquids (ILs) using two quantitative structure-property relationship (QSPR) models. By combining machine learning methods and ionic fragments contribution method, the accuracy and reliability of the prediction models are improved.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Liwang Wang, Wei Liu, Pan Yang, Yulong Chang, Xiaoxu Duan, Lingyu Xiao, Yaoming Hu, Jiwei Wu, Liang Ma, Hualin Wang
Summary: This study investigates the effective phase interfacial area (ae) of hydro-jet cyclones at different injection angles. The results show that a 45 degrees upward incidence angle yields the most favorable flow field characteristics for efficient mass transfer. The significant enhancement in ae of the hydro-jet cyclones offers the advantage of reducing equipment volume and cost savings.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Chuanjun Wu, Jiangzhi Chen, Jiyue Sun, I-Ming Chou, Shenghua Mei, Juezhi Lin, Lei Jiang
Summary: In this study, the solubility of H2S hydrate in water was measured using Raman spectroscopy. The results showed that the solubility increases with temperature under certain equilibrium conditions, and the solubility also depends on pressure and temperature under different equilibrium conditions. A thermodynamic model based on the van der Waals-Platteeuw theory was developed to predict the solubility, demonstrating its accuracy.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Lorenzo Brivio, Serena Meini, Mattia Sponchioni, Davide Moscatelli
Summary: This study investigates the influence of three main parameters and proposes a kinetic model to predict the optimal operating conditions for high yield of dimethyl terephthalate (DMT) in the chemical recycling process of polyethylene terephthalate (PET).
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Hongju Lin, Fanhui Liao, Yanchang Chu, Mingyu Xie, Lun Pan, Yuanyuan Wang, Lijian Leng, Donghai Xu, Le Yang, Gangfeng Ouyang
Summary: A honeycomb NiCo/C-Na catalyst with a micro-meso-macroporous structure has been fabricated and shown to have significantly higher catalytic activity for the decarboxylation of fatty acids. It also proves to be efficient in upgrading sludge HTL bio-crude, resulting in a biofuel with decreased viscosity and increased density.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Xiaoxian Li, Rui Li, Min Lin, Mingde Yang, Yulong Wu
Summary: A series of coated non-noble metal porous carbon catalysts were synthesized and applied to the aqueous-phase deoxygenation of algal bio-oil. One of the catalysts showed excellent deoxygenation selectivity and catalytic activity at 250 degrees C. The catalyst exhibited good hydrothermal stability and the reaction mechanism was proposed based on product analysis and active site analysis.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
M. V. Chudakova, M. V. Popov, P. A. Korovchenko, E. O. Pentsak, A. R. Latypova, P. B. Kurmashov, A. A. Pimenov, E. A. Tsilimbaeva, I. S. Levin, A. G. Bannov, A. V. Kleymenov
Summary: A series of catalysts with different potassium contents were prepared using solution combustion synthesis and characterized using various techniques. The results showed that the potassium content affected the phase composition and texture of the catalysts. The addition of a small amount of potassium resulted in a change in particle size distribution, leading to higher hydrogen yield. The Ni-1%K2O/Al2O3 catalyst exhibited the highest hydrogen yield at temperatures of 675 and 750 degrees Celsius.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Aliakbar Roosta, Nima Rezaei
Summary: In this study, we modified the electrolyte cubic plus association equation of state (e-CPA EoS) and integrated it with two electrical conductivity models to estimate the electrical conductivity of 11 monovalent electrolyte solutions in water. The modified e-CPA model demonstrated better performance and the hybridization with electrical conductivity models resulted in two predictive models for estimating the electrical conduction of dilute and concentrated electrolyte solutions. These predictive models showed relative average percentage deviations (AARD) of 11.15% and 13.87% over wide ranges of temperature and electrolyte concentration.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Haoren Niu, Jianzheng Wang, Qingzhu Jia, Qiang Wang, Jin Zhao, Fangyou Yan
Summary: A study developed two quantitative structure-property relationship models for the complexation performance of alpha- and beta-cyclodextrins and validated their stability and predictive ability through internal and external validation. The models showed robustness and satisfactory performance, as demonstrated by the experimental results and model validations. These models can effectively predict the binding constants between cyclodextrins and various types of molecules, providing valuable tools for cyclodextrin design.
CHEMICAL ENGINEERING SCIENCE
(2024)
