Article
Engineering, Chemical
Liang Li, Runqiu Hao, Xiaoxia Jin, Yachao Hao, Chunming Fu, Chengkai Zhang, Xihui Gu
Summary: A three-dimensional CFD transient model is developed to predict the species concentration distribution in the biodegradation of phenol in an airlift reactor. The model uses the Euler-Euler method coupled with the standard k-epsilon model to determine the gas-liquid flow and predicts the bubble size using the population balance model. A turbulent mass diffusivity model is proposed to simulate the turbulent mass transfer process and predict the species concentration distribution. The model shows good agreement with experimental results and suggests that assuming a constant turbulent Schmidt number is not reasonable.
Article
Energy & Fuels
Yohannis Tobo, Ashraf Lotfi, Luis D. Virla, Nader Mahinpey
Summary: This study successfully overcomes the challenges involved in the experimental investigation of biomass pyrolysis kinetics using a CFD model and simulation. The model provides a detailed characterization and visualization of the pyrolysis kinetics, and predicts the composition of the products obtained from biomass feedstock under specific reactor conditions.
Article
Chemistry, Analytical
Xueer Pan, Wenhao Lian, Nan Zhang, Jingxuan Yang, Zhonglin Zhang, Xiaogang Hao, Guoqing Guan
Summary: A mass transfer model based on the spatial superposition assumption is developed to study the coal pyrolysis process. The simulated volatiles yield using this model shows better agreement with experimental data compared to the conventional Jung-La Nauze equation. It is found that the mass transfer coefficients calculated by the Jung-La Nauze equation are overestimated, indicating an overestimation of the mass transfer process predicted with a uniform structure. The results provide insights into the mass transfer and reaction process in gas-solid fluidized systems by considering the influence of heterogeneous structures.
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
(2023)
Article
Engineering, Chemical
Xueer Pan, Wenhao Lian, Nan Zhang, Jingxuan Yang, Zhonglin Zhang, Xiaogang Hao, Guoqing Guan
Summary: A mass transfer model based on spatial superposition assumption is proposed to reflect the effect of heterogeneous structure on downer mass transfer behavior. This model requires fewer concentration parameters compared to the multi-scale method and is in good agreement with experimental data. The presence of clusters significantly affects gas-solid mass transfer effectiveness, deteriorating the reaction rate. The simulation shows that mass transfer near the inlet region plays a dominant role, while along the flow direction, the influence of the reaction process gradually becomes stronger.
Article
Thermodynamics
Jianqing Wang, Tianqi Liu, Chaozhong Xu, Jiajun Wang, Lian-Fang Feng
Summary: Computational fluid dynamics was used to study the laminar hydrodynamics and heat transfer characteristics of highly viscous fluid in a Sulzer mixer reactor (SMR), which showed better performance in terms of mixing and heat transfer compared to a straight tube heat exchanger (STHE) and a straight tube heat exchanger with segmental baffles (STHE-SG). SMR exhibited more uniform velocity and temperature distributions, as well as a narrower residence time distribution. The regularly arranged heat exchange tubes in SMR helped to continuously twist and split the highly viscous fluid, leading to radial mixing and improved heat transfer efficiency.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Engineering, Chemical
Hariswaran Sitaraman, Ilenia Battiato
Summary: We present well-resolved computational fluid dynamics simulations of a large-scale reverse osmosis membrane-spacer configuration. The study reveals different concentration profile development characteristics at different flow rates and proposes a modified mass-transfer correlation that considers the development of the concentration boundary layer. Additionally, the study finds that a non-uniform arrangement of spacers can significantly reduce pressure drop.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Daniel Borras-Jimenez, Wilber Silva-Lopez, Cesar Nieto-Londono
Summary: This study aims to maximize the Photocatalytic Space-time Yield (PSTY) in a photoelectrocatalytic reactor by selecting a suitable photoreactor flow configuration and operational conditions. Numerical simulation using Computational Fluid Dynamics (CFD) was conducted to model the transport phenomena and reaction kinetics. The results show that the tangential flow configuration generates a higher PSTY compared to the axial flow configuration in both laminar and turbulent regimes. In addition, the use of solar radiation as an external illumination source is necessary to maximize the PSTY.
Article
Engineering, Marine
Suli Lu, Jialun Liu, Robert Hekkenberg
Summary: This article presents a case study on ship rudders to investigate the impacts of different mesh properties on the accuracy of hydrodynamic coefficients obtained by CFD methods. Recommended mesh properties, including Reynolds numbers, domain sizes, and node distributions, are provided for airfoil-shaped profiles. The study clarifies the influences of mesh properties on rudder hydrodynamics and offers applicable settings for other airfoil-shaped profiles.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Review
Biochemistry & Molecular Biology
Long Chen, Binxin Wu
Summary: Membrane distillation (MD) is a promising water treatment technology with various applications, but further research is needed to determine appropriate industrial implementation. Computational fluid dynamics (CFD) has been widely used in analyzing MD processes and developing novel membranes, but there is still a need for more comprehensive and in-depth research in the field.
Review
Engineering, Chemical
Zongzhuang Sun, Xin Zhou, Zhaoning Song, Hao Yan, Yongxiao Tuo, Yibin Liu, Hui Zhao, Xiaobo Chen, Xiang Feng, De Chen, Chaohe Yang
Summary: In this study, the gas-phase propene epoxidation reaction in a fixed bed reactor with randomly packed spherical particles of different sizes (6, 8, and 10 mm) was simulated using computational fluid dynamics. The 6 mm particle diameter model showed a more uniform flow distribution, higher thermal conductivity, and lower temperature compared to the 8 mm and 10 mm models. Additionally, the 6 mm model exhibited a more uniform reaction rate within the particles. This research has significant implications for the design and scale-up of industrial reactors for propene epoxidation.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Chemical
Jose. T. Lopez-Maldonado, Sebastian Salazar-Colores, Saul Piedra, Fernando F. Rivera
Summary: Electrochemical reactors with diverse flow channel designs have been extensively studied at lab and bench scales, and scaled up for semipilot and industrial levels. This work evaluates the hydrodynamic performance of different electrochemical reactor designs and quantifies their effect on velocity magnitude through computational and experimental studies. The findings of this experimental technique agreed with those obtained by the traditional experimental flow characterization technique.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Engineering, Environmental
Rebecca L. Gibson, Mark J. H. Simmons, E. Hugh Stitt, Li Liu, Robert W. Gallen
Summary: Computational fluid dynamics (CFD) is used to characterize transport phenomena in thermal analysis reactors. Heat and mass transport issues were found in pan-style and non-uniform diameter tubular reactors, while uniform diameter tubular reactors are suitable for kinetic experimentation with the use of dimensionless analysis.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Thermodynamics
Diego Alcaniz, Paolo Caccavale, Maria Valeria De Bonis, Ruth de los Reyes, Maria Dolores Ortola, Gianpaolo Ruocco
Summary: A new fluid heater based on BCET was proposed in this paper, with fully-dimensional thermo-fluid analysis implemented to achieve more uniform and effective heat transfer to temperature-sensitive working fluids. Through geometry optimization with internal baffles, the uncontrolled temperature excess was significantly reduced, while the pressure drop across the flow device was also lowered.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Thermodynamics
Jianqing Wang, Guancheng Tan, Jiajun Wang, Lian-Fang Feng
Summary: This study applied computational fluid dynamics to analyze the hydrodynamics, heat transfer, and mixing of highly viscous non-Newtonian fluid in a Sulzer mixer reactor. The study found that increasing the rheological parameters led to higher viscosity and power consumption. The yield stress and power-law index significantly affected shear distribution, residence time distribution, and mixing efficiency. Increasing the inlet velocity improved heat transfer performance and mixing efficiency.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Engineering, Chemical
Maulana G. Nugraha, Ronnie Andersson, Bengt Andersson
Summary: This study introduces new models for mass transfer to spheres under three different conditions: mass transfer without Stefan flow, mass transfer with even Stefan flow, and mass transfer with uneven flux driven Stefan flow. The new models, derived from high resolved computational fluid dynamic simulations, show improved accuracy and reduced relative error, especially for higher Sc numbers.
CHEMICAL ENGINEERING SCIENCE
(2022)
