Article
Energy & Fuels
Marie Placha, Martin Isoz, Petr Koci, Matthew P. Jones, Milos Svoboda, David S. Eastwood, Andrew P. E. York
Summary: A transient pore-scale model for particle deposit formation in a catalytic filter wall is introduced and validated. The model is used to simulate the soot filtration process in different microstructures and provides insights into its efficiency and pressure drop.
Article
Engineering, Environmental
Jan Nemec, Marie Placha, Petr Koci
Summary: A new extension of a 1D mathematical model is proposed to describe diffusion limitation in a catalytic filter wall. The model considers transport limitations in both flowing gas inside free pores and in the coated catalyst, as well as Langmuir-Hinshelwood reaction kinetics with inhibition effects. By comparing the computed 1D concentration profiles with detailed 3D pore-scale simulations, the best agreement is achieved when gas-in-pores and intra-catalyst diffusion with LH effectiveness factor are considered. The extended model predicts the presence of undesired reactant slip at high flow rates, which was not possible with previously published models.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Environmental Sciences
Yachao Wang, Sheng Su, Yitu Lai, Wanyou Luo, Pan Hou, Tao Lyu, Yunshan Ge
Summary: Particles larger than 10 nm from engine exhaust are causing global concerns. This study investigated the impact of EGR on SPN10 (solid particles larger than 10 nm) emissions from gasoline vehicles. The results showed that vehicles with EGR were more likely to exceed the current limit if the cut-off size was reduced to 10 nm. Specifically, during the WLTC test, EGR increased SPN10 emission factors by 2-3 times depending on vehicle powertrains. Notably, active engagement of EGR resulted in a significant increase in SPN10 emissions, while a constant EGR rate led to a decrease. EGR and enriched fuel-air mixture were identified as critical factors contributing to the increased SPN10 emissions.
ENVIRONMENT INTERNATIONAL
(2023)
Article
Mechanics
Hai-Ning Wang, Wei-Xi Huang, Chun-Xiao Xu
Summary: The study developed a new method for treating the near-wall region in LES based on off-wall boundary conditions, combining minimum flow units and the predictive inner-outer model for wall turbulence. By predicting the fluctuating near-wall velocity field in real-time to provide boundary conditions on the off-wall boundary, the method does not assume a velocity profile and incorporates turbulent structures. Results show the method induces a shorter transition zone in the wall-normal direction compared to other wall models, with the validity and robustness of the method verified by reasonable simulation results of channel flows under different computational parameters.
Article
Mechanics
Zhideng Zhou, Xiang I. A. Yang, Fengshun Zhang, Xiaolei Yang
Summary: In this study, a wall model is developed using the wall-resolved large-eddy simulation (WRLES) data of flow over periodic hills (PH) and the law of the wall (LoW) for data-driven wall-modeled large-eddy simulations of various wall-bounded turbulent flows. A feedforward neural network (FNN) is employed to construct the model. The performance of the obtained FNN_PH-LoW model is successfully evaluated using the direct numerical simulation data of turbulent channel flows and the WRLES data of PH cases, and it is applied to turbulent channel flows with a wide range of Reynolds numbers.
Article
Nuclear Science & Technology
N. Asakura, K. Hoshino, S. Kakudate, F. Subba, J. -h. You, S. Wiesen, T. D. Rognlien, R. Ding, S. Kwon
Summary: The power exhaust concept and divertor design are critical issues in tokamak DEMO design activities worldwide. Radiative cooling is commonly used for power fusion scenarios. Challenges include increasing main plasma radiation fraction for ITER-level P-sep/R-p designs, extending ITER divertor geometry, and optimizing the divertor design for large P-sep. Power exhaust simulations with large P-sep have been performed, showing extended plasma detachment and reduced heat load with the right divertor radiation fraction.
NUCLEAR MATERIALS AND ENERGY
(2023)
Article
Chemistry, Multidisciplinary
Alberto Bosca, Antonio Ladron-de-Guevara, Jorge Pedros, Javier Martinez, Rajveer Fandan, Fernando Calle
Summary: The growth of crystalline graphene through cold-wall chemical vapor deposition relies on catalyst pretreatment, pressure, temperature, and gas flow rates. A comprehensive study is required to translate the optimal thermodynamic configuration into industry-ready CVD cold-wall reactors, which can increase growth area and efficiency while reducing costs. This study investigates how thermodynamic parameters affect growth dynamics and material quality in a cold-wall reactor with high precursor flow rate, demonstrating the suitability of this regime for achieving high-quality material.
CRYSTAL GROWTH & DESIGN
(2023)
Letter
Mechanics
Guo-Zhen Ma, Chun-Xiao Xu, Hyung Jin Sung, Wei-Xi Huang
Summary: This paper proposes a roughness scaling method based on the direct numerical simulation of turbulent channel flow over three-dimensional sinusoidal rough walls in a transitionally rough regime. A new coupling scale is defined and the relationships between various parameters are explored.
Article
Environmental Sciences
Yanzhao Hao, Shunxi Deng, Zhaowen Qiu, Zhenzhen Lu, Hui Song, Naiwang Yang
Summary: The study found that the emissions of PM2.5 components decreased significantly from China IV to China V, with most water soluble ions and elements contributing more to PM2.5. In China IV LDVs, the emissions of PM2.5 components also decreased when switching to natural gas fuel.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Engineering, Chemical
Rudolf Pecinka, Miroslav Blazek, Richard Knopp, Petr Koci, Andrew York
Summary: In this study, a method for experimentally observing mass-transfer limitations in catalytic filter walls and their impact on the outlet conversion of gaseous pollutants is presented. The results show that the uniform distribution of catalyst inside the filter pores has a significant effect on CO slip phenomenon at higher flow rates.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Nuclear Science & Technology
Vladimir N. N. Blinkov, Oleg I. I. Melikhov, Vladimir I. I. Melikhov, Andrey V. S. Kapustin, Kirill S. N. Dolganov, Dmitry Yu E. Tomashchik, Vladimir N. S. Semenov, Artem E. Tarasov, Sergey S. Selkin
Summary: The applicability of the one-dimensional two-fluid model in predicting vapor void fraction and frictional pressure drop in upward and downward two-phase flows has been studied. Existing empirical models for interfacial and wall friction show deficiencies in predicting low velocity downward flow.
NUCLEAR ENGINEERING AND DESIGN
(2022)
Article
Mechanics
Ming Yu, PengXin Liu, YaLu Fu, ZhiGong Tang, XianXu Yuan
Summary: This two-part study investigates the effects of Mach number and wall temperature on the statistics of wall shear stress, pressure, and heat flux fluctuations in compressible wall-bounded turbulence. The study found that these statistics vary with the friction Mach number, and the correlations between wall shear stress, pressure, and heat flux fluctuations increase with the Mach number, indicating the interactions between dynamic and thermodynamic processes. The analysis of spectra and probability density functions suggests that the increased correlation is induced by intermittent traveling wave packets among streaky structures. The study also highlights the importance of understanding the characteristics of compressible wall-bounded turbulence.
Article
Multidisciplinary Sciences
Ramin Zakeri, Reza Zakeri
Summary: This paper presents a study on the hybrid of mixed electrolysis and fluids chemical reaction (HEFR) method for creating a fast displacement mechanism. The results show that this method has a quick response time, low construction cost, and is practical for general and frequent uses.
SCIENTIFIC REPORTS
(2022)
Article
Mechanics
Yiyun Peng, Xiaolong He, Haonan Peng, Yuqing Lin, Jianmin Zhang
Summary: A new pseudopotential lattice Boltzmann model has been developed to simulate multiphase flow with a large density ratio and wide viscosity ratio, and it has been validated to accurately simulate the collapse process of single and multiple cavitation bubbles.
Article
Thermodynamics
Pulkit Kumar, Ajit Kumar Parwani, Vivek Vitankar
Summary: This study presents simulations of the chemical looping combustion process with a focus on the hydrodynamic behavior of the air reactor and reactions in the fuel reactor. The results show high turbulence and chaotic flow in the gas-solid regions of the air reactor, as well as favorable pressure gradients for particle movement. Additionally, complete formation of CO2 and H2O in the fuel reactor is achieved within 20 seconds.
HEAT TRANSFER ENGINEERING
(2022)
Article
Chemistry, Physical
Elifkuebra Oezkan, Pascal Cop, Felix Benfer, Alexander Hofmann, Martin Votsmeier, Juan M. Guerra, Marcel Giar, Christian Heiliger, Herbert Over, Bernd M. Smarsly
JOURNAL OF PHYSICAL CHEMISTRY C
(2020)
Article
Chemistry, Applied
M. Bendrich, A. Scheuer, M. Votsmeier
Summary: The study compared a mechanistic model and a global model in predicting NOx conversion rates, with the mechanistic model showing better performance in colder cycles due to its consideration of nitrates. Both models performed similarly in hotter cycles as no ammonium nitrate accumulates at high temperatures. Despite the additional complexity in the mechanistic model, simulation times remained comparable. Additionally, a simple NH3 dosing strategy was found to increase NOx conversion rates, demonstrating the model's utility in optimizing catalyst potential during driving cycles.
Article
Engineering, Chemical
Igor Belot, David Vidal, Martin Votsmeier, Robert E. Hayes, Francois Bertrand
CHEMICAL ENGINEERING SCIENCE
(2020)
Article
Chemistry, Multidisciplinary
Elifkubra Oezkan, Felix Badaczewski, Pascal Cop, Sebastian Werner, Alexander Hofmann, Martin Votsmeier, Heinz Amenitsch, Bernd M. Smarsly
Article
Chemistry, Physical
Andreas M. Gaenzler, Benjamin Betz, Sina Baier-Stegmaier, Stephanie Belin, Valerie Briois, Martin Votsmeier, Maria Casapu
JOURNAL OF PHYSICAL CHEMISTRY C
(2020)
Review
Chemistry, Physical
Abhaya K. Datye, Martin Votsmeier
Summary: This review discusses the use, synthesis routes, and materials of exhaust emissions catalysts, as well as the challenges faced in the field. New material concepts include single-atom catalysts, two-dimensional materials, three-dimensional structures, but they need to overcome various challenges before being applied to exhaust treatment in cars and trucks.
Article
Engineering, Chemical
Ileana M. Vega Mesquida, Ivan Cornejo, Petr Nikrityuk, Robert Greiner, Martin Votsmeier, Robert E. Hayes
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2020)
Article
Engineering, Environmental
Igor Belot, David Vidal, Robert Greiner, Martin Votsmeier, Robert E. Hayes, Francois Bertrand
Summary: The impact of catalyst distribution within the porous wall of a coated gasoline particulate filter on its catalytic performance is significant. Improvements in catalytic conversion and washcoat effectiveness are observed when the washcoat distribution is uniform, but the benefits are limited to the transitional regime.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Environmental
Igor Belot, Yixun Sun, David Vidal, Martin Votsmeier, Philippe Causse, Francois Trochu, Francois Bertrand
Summary: The study proposes an experimental magnified twin approach based on kinematic similarity to characterize the permeability of printed magnified porous wall sections, presenting comparisons between numerical, semi-analytical, and experimental predictions on the impact of coating amount and degree of uniformity on wall permeability. Despite the sensitivity of permeability to pore space characteristics, a good agreement between simulations and experiments is reported, indicating the potential of the proposed method in porous media applications.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Elifkubra Ozkan, Alexander Hofmann, Martin Votsmeier, Wu Wang, Xiaohui Huang, Christian Kuebel, Felix Badaczewski, Kevin Turke, Sebastian Werner, Bernd M. Smarsly
Summary: This study investigated the pore structure of a mesoporous cerium oxide material, revealing that it maintains stable mesoporosity at high temperatures and has potential applications in high-temperature catalysis. Various characterization techniques were used to elucidate the structural evolution from heat treatment to aging, showing that the 3D spatial arrangement of primary particles plays a key role in the thermal stability of the hierarchical mesopore structure.
Article
Engineering, Chemical
Florian Maurer, Andreas Gaenzler, Patrick Lott, Benjamin Betz, Martin Votsmeier, Stephane Loridant, Philippe Vernoux, Vadim Murzin, Benjamin Bornmann, Ronald Frahm, Olaf Deutschmann, Maria Casapu, Jan-Dierk Grunwaldt
Summary: The study found that reductive pulse activation leads to an increase in overall catalyst activity and the generation of different particle size zones within the catalyst bed. Activation temperature and pulse length influence the noble metal particle size, and this activation method could potentially be applied to industrially relevant catalysts in the future.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Engineering, Chemical
Michelle Bendrich, Bastian Opitz, Alexander Scheuer, Robert E. Hayes, Martin Votsmeier
Summary: This paper compares the performance of two catalytic systems for removing nitrogen oxides from automotive exhaust using SCR through computational simulation. The results show that adding an ammonia slip catalyst can reduce slip and increase NOx conversion, with benefits for dealing with different dosing situations.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Engineering, Environmental
Xiangxiao Kong, Kerry Chen, Robert Greiner, Martin Votsmeier, Igor Belot, David Vidal, Francois Bertrand, Robert E. Hayes, Jason S. Olfert
Summary: Gasoline particulate filters (GPFs) are effective in reducing particle emissions from gasoline direct injection (GDI) engines. This study examined the filtration efficiency and pressure drop of three GPFs with different in-wall washcoat volumes, finding that filtration efficiency is influenced by particle size, soot loading, and space velocity. The results indicate that coated filters have the highest filtration efficiency at high levels of soot accumulation, but also come with a higher rate of pressure drop increase compared to bare filters.
EMISSION CONTROL SCIENCE AND TECHNOLOGY
(2021)
Article
Engineering, Chemical
Matthias Bonarens, Robert Greiner, Martin Votsmeier, David Vidal
Summary: An analytical model for the performance of clean polydisperse packed beds is derived based on classical packed bed filtration theory in this paper. The proposed model shows considerably better agreement with numerical simulation results compared to previous analytical models.
JOURNAL OF AEROSOL SCIENCE
(2022)
Article
Engineering, Chemical
Felix A. Doeppel, Martin Votsmeier
Summary: Machine learning can accelerate simulations of catalytic systems by interpolating precomputed solutions of rate equations. Interpolation quality is improved when reaction rates are mapped using logarithmic scaling. However, this method is limited to reaction systems that strictly maintain positive or negative source terms throughout the relevant conditions. A new approach is proposed to overcome this limitation by interpolating the forward and reverse rates of rate-determining reactions. The new method achieves higher accuracy compared to established approaches and outperforms spline interpolation in terms of interpolation time, storage space, and required training data.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Chemistry, Physical
Bolun Yu, Denan Li, Qianqian Zhu, Shufan Yao, Lifeng Zhang, Yanshuo Li, Zhenxin Zhang
Summary: This study successfully improved the catalytic activity of a zeolitic octahedral metal oxide by incorporating a single zinc species into its micropore. The zinc incorporation achieved a high ethane conversion rate and ethylene selectivity. Mechanism study showed that the isolated zinc site played a crucial role in activating oxygen and ethane, as well as stabilizing intermediates and transition states.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Ruoqi Liu, Hao Fei, Jian Wang, Ting Guo, Fangyang Liu, Zhuangzhi Wu, Dezhi Wang
Summary: This work successfully synthesized a high-performing S-enriched MoS2 catalyst for electrocatalytic nitrogen reduction reaction (NRR), demonstrating high activity and selectivity. The synergistic effect of the 1T phase and bridging S22- species was shown to play a positive role in NRR performances, and DFT calculations revealed the mechanism behind the improved performance.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Pan Xia, Lele Zhao, Xi Chen, Zhihong Ye, Zhihong Zheng, Qiang He, Ignasi Sires
Summary: This study presents a modified gas-diffusion electrode (GDE) for highly efficient and stable H2O2 electrosynthesis by using trace polymethylhydrosiloxane (PMHS). DFT calculations provide an in-depth understanding of the roles of PMHS functional groups.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Kwangchol Ri, Songsik Pak, Dunyu Sun, Qiang Zhong, Shaogui Yang, Songil Sin, Leliang Wu, Yue Sun, Hui Cao, Chunxiao Han, Chenmin Xu, Yazi Liu, Huan He, Shiyin Li, Cheng Sun
Summary: Different B-doped rGO catalysts were synthesized and their 2e- oxygen reduction reaction (ORR) performance was investigated. It was found that the 2e- ORR selectivity of B-doped rGO was influenced by the B content and oxygen mass transfer conditions. The synthesized catalyst exhibited high 2e- ORR selectivity and was capable of degrading organic pollutants continuously.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Li Lv, Lin Lei, Qi-Wen Chen, Cheng-Li Yin, Huiqing Fan, Jian-Ping Zhou
Summary: Monoclinic phase La2Ti2O7 and orthorhombic phase Bi4Ti3O12 are widely used in photocatalysis due to their layered crystal structure. The electronic structures of these phases play a crucial role in their photocatalytic activity. Heat treatment in a nitrogen atmosphere introduces more oxygen vacancies into the S-scheme heterojunction, leading to enhanced NO removal efficiency.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Choe Earn Choong, Minhee Kim, Jun Sup Lim, Young June Hong, Geon Joon Lee, Keun Hwa Chae, In Wook Nah, Yeomin Yoon, Eun Ha Choi, Min Jang
Summary: In this study, the synergistic effect between argon-plasma-system (AP) and catalysts in promoting the production of reactive species for water remediation was investigated. By altering the oxygen vacancies concentration of CeO2/Bi2O3 catalyst, the production of hydrated electrons was stimulated for PFOA removal. The results showed that the built-in electric field in the Bi/Ce0.43 interface enhanced electron migration and eaq- generation, leading to improved PFOA removal efficiency.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Yushan Wu, Di Xu, Yanfei Xu, Xin Tian, Mingyue Ding
Summary: Efficient synthesis of primary amines from carbonyl compounds was achieved via reductive amination using Ru@NC-Al2O3 as a catalyst, exhibiting high activity and selectivity under mild conditions.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Yilan Jiang, Peifang Wang, Tingyue Chen, Keyi Gao, Yiran Xiong, Yin Lu, Dionysios D. Dionysiou, Dawei Wang
Summary: By controlling the content of Co and Ni in Co1-xNixFe2O4, the production of O-1(2) from H2O2 can be regulated. NiFe2O4, with the lowest lattice distortion degree, can efficiently produce O-1(2) as the dominant reactive oxygen species. The system also exhibits significant resistance to water matrix interference.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Shuai Feng, Donglian Li, Hao Dong, Song Xie, Yaping Miao, Xuming Zhang, Biao Gao, Paul K. Chu, Xiang Peng
Summary: In this study, MoO2/Mo2N heterostructures were prepared by regulating the coordination of Mo atoms. The electrocatalyst exhibits high current density and excellent stability for hydrogen evolution reaction.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Jia-Cheng E. Yang, Min -Ping Zhu, Daqin Guan, Baoling Yuan, Darren Delai Sun, Chenghua Sun, Ming-Lai Fu
Summary: This study successfully modulated the electron configuration and spin state of millimetric metal catalysts by adjusting the support curvature radius. The electronic structure-oriented spin catalysis was found to affect the degradation of pollutants, providing new insights for the design and production of highly active, reusable, and stable catalysts.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Tao Zhong, Su Tang, Wenbin Huang, Wei Liu, Huinan Zhao, Lingling Hu, Shuanghong Tian, Chun He
Summary: In this study, a highly efficient photocatalyst for the elimination of CH3SH was developed by engineering different crystal facets and coupling them with PHI. Cu (111)/PHI exhibited the highest elimination efficiency and showed good stability and reusability. The enhanced surface electron pump effect and effective adsorption mechanisms were revealed through comprehensive characterizations and DFT calculations.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Physical
Feifei Yang, Tianyu Zhang, Jiankang Zhao, Wei Zhou, Nicole J. Libretto, Jeffrey T. Miller
Summary: A Ni3Sn intermetallic nano particle was found to have geometrically isolated Ni sites that could selectively cleave C-O bonds in biomass derivatives. This nano particle showed high activity and selectivity towards 2-methylfuran, unlike Ni nanoparticles that produced other unwanted products derived from the aromatic rings.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2024)
Article
Chemistry, Physical
Lulu Qiao, Di Liu, Anquan Zhu, Jinxian Feng, Pengfei Zhou, Chunfa Liu, Kar Wei Ng, Hui Pan
Summary: This study reveals that surface evolution plays a crucial role in enhancing the electrocatalytic performance of transition metal oxides for electrochemical nitrate reduction reaction (e-NO3RR). Incorporating nickel into Co3O4 can promote surface reconstruction and improve the adsorption of intermediates and reduce energy barriers, leading to enhanced catalytic performance. The reconstructed cobalt-nickel hydroxides (CoyNi1_y(OH)2) on the catalyst's surface serve as the active phase.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2024)
Article
Chemistry, Physical
Xinyu Song, Yang Shi, Zelin Wu, Bingkun Huang, Xinhao Wang, Heng Zhang, Peng Zhou, Wen Liu, Zhicheng Pan, Zhaokun Xiong, Bo Lai
Summary: This study explores the discriminative activities and mechanisms for activation of O-O bond in peroxy compounds via single-atom catalysts (SACs) with higher coordination numbers (M-N5). The atomic catalyst (Fe-SAC) with Fe-N5 as the active center was constructed, effectively activating peroxymonosulfate (PMS), peroxydisulfate (PDS), and hydrogen peroxide (H2O2). The study demonstrates the degradation efficiencies of acyclovir are related to the O-O bond length in different peroxy compounds, and reveals the discriminative mechanisms for activation of O-O bond in different Fenton-like systems.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2024)
Article
Chemistry, Physical
Yangzhuo He, Hong Qin, Ziwei Wang, Han Wang, Yuan Zhu, Chengyun Zhou, Ying Zeng, Yicheng Li, Piao Xu, Guangming Zeng
Summary: A dual-metal-organic framework (MOF) assisted strategy was proposed to construct a magnetic Fe-Mn oxycarbide anchored on N-doped carbon for peroxymonosulfate (PMS) activation. The FeMn@NC-800 catalyst exhibited superior activity with almost 100% degradation of sulfamethazine (SMZ) in 30 minutes. The study provided insights for the rational design of high-performance heterogeneous catalysts and proposed a novel nonradical-based catalytic oxidation for environmental cleaning.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2024)