Article
Meteorology & Atmospheric Sciences
L. Umek, A. Gohm, M. Haid, H. C. Ward, M. W. Rotach
Summary: This study investigates the erosion processes of cold-air pools (CAP) in an Alpine valley during south foehn through large-eddy simulation (LES), showing the importance of turbulent heating and advective cooling in CAP evolution. The study emphasizes the significance of shear-flow instability and highlights the large magnitudes of advective and turbulent heating compared to their net effect.
QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY
(2021)
Article
Mechanics
Kaijun Li, Wei Xu, Linye Song, Xinghui Zhang, Cong Zhang, Jing Hua
Summary: In this study, the impact of indoor wind speed and human movement on the propagation and diffusion of cough ejected droplets was investigated using computational fluid dynamics. The results showed that indoor airflow and human-induced wake play important roles in the spread of droplets. The combined effect of indoor air velocity and human movement leads to a complex indoor flow field, which increases the risk of infection by delaying the deposition time of certain droplet sizes and facilitating the rapid spread of smaller droplets to distant locations.
Article
Thermodynamics
Wei Xu, Pin Li, Huixia Liu, Hao Wang, Xiao Wang
Summary: This study focused on the formation of molten pool during laser transmission welding, indicating that heat conduction plays a more significant role than convection, and temperature is the key factor in molten pool formation.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2022)
Article
Environmental Sciences
Amir Ghaderi, Saeed Abbasi, Silvia Di Francesco
Summary: This study conducted numerical simulations to investigate the influence of geometric characteristics of pooled steps on energy dissipation, flow patterns, velocity rates, and pressure distributions over a spillway. Results showed that the flat step configuration had the best energy dissipation performance. The efficiency performance of the pooled structure improved by about 5.8% with the notched pooled step configuration, but the pool configuration did not significantly affect the location of air entrainment.
Article
Nuclear Science & Technology
Y. Cordova, D. Blanco, Y. Rivera, C. Berna, J. L. Munoz-Cobo, A. Escriva
Summary: Turbulent jet discharges in subcooled water pools play a crucial role in the safety systems of nuclear power plants. In this field, the gas and liquid flow in these systems have been extensively studied using a combination of experiments, theoretical models, and CFD simulations.
NUCLEAR ENGINEERING AND TECHNOLOGY
(2023)
Article
Energy & Fuels
Piotr Ciuman, Jan Kaczmarczyk
Summary: Ventilation of an indoor swimming pool is energy consuming, but reduction of supply air volume flow rate can lead to lower energy expenditure. The use of two-stage heat recovery can further reduce energy consumption.
Review
Thermodynamics
Hantao Jiang, Yingwen Liu, Huaqiang Chu
Summary: This paper provides a comprehensive review of computational methods used in the study of pool boiling. Different methods at macroscopic, mesoscopic, and nanoscale are evaluated for their effectiveness in modeling bubble dynamics. The challenges and future directions for pool boiling simulations are also discussed.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Thermodynamics
Lin Shi, Laihege Jiang, Ming Gao
Summary: In this study, a three-dimensional transient numerical model is established to investigate the melt pool dynamics in oscillating laser-arc hybrid welding (O-LAHW). The results show that beam oscillation improves the melt pool morphology and reduces heat accumulation. The energy coupling between the oscillating beam and arc, as well as the dynamic keyhole-induced convection/vortex, significantly improves the temperature field. The oscillating shear force drives a powerful vortex that dominates the flow field and stabilizes the melt pool.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Hao Jia, Long Cao, Shuiqi Fu, Hua Wen, Guohong Ma
Summary: A 3D transient numerical model is developed to study the effect of ultrasonic waves on the molten pools in ultrasonic-assisted metal inert gas welding (U-MIG). The model considers droplet impact, liquid metal oscillation, and dynamic variations in arc pressure. The simulations show good agreement with experimental results, confirming the validity of the model and the accuracy of the conclusions. This investigation reveals the impact of ultrasonic waves on the temperature field and fluid flow of the U-MIG welding pool, providing a foundation for optimizing and applying the ultrasonic hybrid welding process.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Jiang Chu, Xiao Wang, Youjuan Ma, Huixia Liu
Summary: Pretreatment of metal surfaces with micro-pits significantly increases the strength of laser transmission joints between polymers and metals. A 3D transient finite element model was built to study the flow field and transient temperature field of the molten polymer flow in the lap joint between polyethylene terephthalate and SUS304 stainless steel. It was found that the joint strength is the highest under specific conditions.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Sudhanshu Pandey, Hariharan Kallath, Ho Yeon Choi, Thierry Sibilli, June Kee Min, Jason Chetwynd-Chatwin, Man Yeong Ha
Summary: This study investigates the aerothermal performance of a CCA heat exchanger with flow nonuniformities. The results show that heat transfer rate increases when the flow nonuniformity is symmetric and decreases when the flow nonuniformity is asymmetric.
APPLIED THERMAL ENGINEERING
(2022)
Article
Engineering, Civil
Wangru Wei, Jun Deng, Weilin Xu
Summary: This study analyzed the effects of approach water velocity and area residual of tunnel cross-section on air supply to free-surface water flows using numerical simulation. Results showed a relationship between air demand and area residual, providing reference for air ventilation design of flood discharge tunnels.
JOURNAL OF HYDRAULIC RESEARCH
(2021)
Article
Construction & Building Technology
Xueliang Li, Fan Wu, Yu Tao, Mingzhi Yang, Renze Xu, Dmitri Vainchtein
Summary: This study investigates the decrease in air flux through the air-conditioning unit on a running high-speed train and designs flow deflectors to alleviate the flux drop. The study finds that the cross-sectional shape of deflectors significantly affects the air flux drop and changes the flow conditions above the condensing outlets. The extra aerodynamic drag brought by the deflectors is also computed and analyzed.
BUILDING AND ENVIRONMENT
(2022)
Article
Mechanics
Xiujie Li, Cheuk Ming Mak, Zhengtao Ai, Kuen Wai Ma, Hai Ming Wong
Summary: This study investigates the impacts of environmental conditions (changes in ventilation location, ventilation rate, and relative humidity) and variations in dental patient's breathing rate on droplet transmission during dental service. Computational fluid dynamics simulation was performed to analyze the effects of different factors on droplet deposition in the dental surgery environment. The results indicate that most droplets deposited near the dental treatment region, with the patient's torso, face, and floor accounting for the majority. Changes in ventilation location had minimal impact on the deposition of larger droplets, while variations in ventilation rate and patient's breathing rate had negligible effects.
Article
Mechanics
Luan Ngoc Mai, Trung Hieu Vu, Thien Xuan Dinh, Hoai Duc Vu, Canh-Dung Tran, Van Thanh Dau, Hieu Khanh Ngo
Summary: In this paper, the behavior of the cone-jet mode of fluid by electrohydrodynamic atomization is investigated through numerical simulations. The effects of liquid wetting and corona discharge are taken into account. Experimental data and various analyses are used to verify and validate the numerical method. The results show that factors such as electrical conductivity, surface tension, flow rate, and fluid viscosity have significant impacts on the electrospray characteristics.
Article
Environmental Sciences
Ulas Im, Roberto Bianconi, Efisio Solazzo, Ioannis Kioutsioukis, Alba Badia, Alessandra Balzarini, Rocio Baro, Roberto Bellasio, Dominik Brunner, Charles Chemel, Gabriele Curci, Hugo Denier van der Gon, Johannes Flemming, Renate Forkel, Lea Giordano, Pedro Jimenez-Guerrero, Marcus Hirtl, Alma Hodzic, Luka Honzak, Oriol Jorba, Christoph Knote, Paul A. Makar, Astrid Manders-Groot, Lucy Neal, Juan L. Perez, Guido Pirovano, George Pouliot, Roberto San Jose, Nicholas Savage, Wolfram Schroder, Ranjeet S. Sokhi, Dimiter Syrakov, Alfreida Torian, Paolo Tuccella, Kai Wang, Johannes Werhahn, Ralf Wolke, Rahela Zabkar, Yang Zhang, Junhua Zhang, Christian Hogrefe, Stefano Galmarini
ATMOSPHERIC ENVIRONMENT
(2015)
Article
Environmental Sciences
Ulas Im, Roberto Bianconi, Efisio Solazzo, Ioannis Kioutsioukis, Alba Badia, Alessandra Balzarini, Rocio Baro, Roberto Bellasio, Dominik Brunner, Charles Chemel, Gabriele Curci, Johannes Flemming, Renate Forkel, Lea Giordano, Pedro Jimenez-Guerrero, Marcus Hirtl, Alma Hodzic, Luka Honzak, Oriol Jorba, Christoph Knote, Jeroen J. P. Kuenen, Paul A. Makar, Astrid Manders-Groot, Lucy Neal, Juan L. Perez, Guido Pirovano, George Pouliot, Roberto San Jose, Nicholas Savage, Wolfram Schroder, Ranjeet S. Sokhi, Dimiter Syrakov, Alfreida Torian, Paolo Tuccella, Johannes Werhahn, Ralf Wolke, Khairunnisa Yahya, Rahela Zabkar, Yang Zhang, Junhua Zhang, Christian Hogrefe, Stefano Galmarini
ATMOSPHERIC ENVIRONMENT
(2015)
Article
Environmental Sciences
Charles Chemel, Gabriele Arduini, Chantal Staquet, Yann Largeron, Dominique Legain, Diane Tzanos, Alexandre Paci
ATMOSPHERIC ENVIRONMENT
(2016)
Article
Environmental Sciences
Bernard Fisher, Charles Chemel, Ranjeet Sokhi, Roger Timmis
ATMOSPHERIC POLLUTION RESEARCH
(2016)
Article
Meteorology & Atmospheric Sciences
Gabriele Arduini, Charles Chemel, Chantal Staquet
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2017)
Article
Meteorology & Atmospheric Sciences
Julian Quimbayo-Duarte, Chantal Staquet, Charles Chemel, Gabriele Arduini
BOUNDARY-LAYER METEOROLOGY
(2019)
Article
Environmental Sciences
Julian Quimbayo-Duarte, Chantal Staquet, Charles Chemel, Gabriele Arduini
Article
Meteorology & Atmospheric Sciences
G. Arduini, C. Chemel, C. Staquet
QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY
(2020)
Article
Environmental Sciences
Julian Quimbayo-Duarte, Charles Chemel, Chantal Staquet, Florence Troude, Gabriele Arduini
Summary: This study examines the severe air pollution in the Arve river valley, attributing it mostly to local emission sources with the central basin-shaped section being the most affected. While other valley sections show a more complex distribution of pollution, with contributions from both local and non-local sources being significant.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Meteorology & Atmospheric Sciences
John Tolladay, Charles Chemel
Summary: The study demonstrates that forest canopies affect airflow dynamics and current methods of representing tall canopies in numerical simulations have deficiencies. Explicit modelling of a forest canopy is lacking in community numerical weather prediction models.
BOUNDARY-LAYER METEOROLOGY
(2021)
Article
Meteorology & Atmospheric Sciences
Joseph Girdwood, Helen Smith, Warren Stanley, Zbigniew Ulanowski, Chris Stopford, Charles Chemel, Konstantinos-Matthaios Doulgeris, David Brus, David Campbell, Robert Mackenzie
ATMOSPHERIC MEASUREMENT TECHNIQUES
(2020)
Article
Meteorology & Atmospheric Sciences
N. R. P. Harris, L. J. Carpenter, J. D. Lee, G. Vaughan, M. T. Filus, R. L. Jones, B. OuYang, J. A. Pyle, A. D. Robinson, S. J. Andrews, A. C. Lewis, J. Minaeian, A. Vaughan, J. R. Dorsey, M. W. Gallagher, M. Le Breton, R. Newton, C. J. Percival, H. M. A. Ricketts, S. J-B Bauguitte, G. J. Nott, A. Wellpott, M. J. Ashfold, J. Flemming, R. Butler, P. I. Palmer, P. H. Kaye, C. Stopford, C. Chemel, H. Boesch, N. Humpage, A. Vick, A. R. MacKenzie, R. Hyde, P. Angelov, E. Meneguz, A. J. Manning
BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY
(2017)
Article
Environmental Sciences
Ioannis Kioutsioukis, Ulas Im, Efisio Solazzo, Roberto Bianconi, Alba Badia, Alessandra Balzarini, Rocio Baro, Roberto Bellasio, Dominik Brunner, Charles Chemel, Gabriele Curci, Hugo Denier van der Gon, Johannes Flemming, Renate Forkel, Lea Giordano, Pedro Jimenez-Guerrero, Marcus Hirtl, Oriol Jorba, Astrid Manders-Groot, Lucy Neal, Juan L. Perez, Guidio Pirovano, Roberto San Jose, Nicholas Savage, Wolfram Schroder, Ranjeet S. Sokhi, Dimiter Syrakov, Paolo Tuccella, Johannes Werhahn, Ralf Wolke, Christian Hogrefe, Stefano Galmarini
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2016)
Article
Environmental Sciences
R. Newton, G. Vaughan, H. M. A. Ricketts, L. L. Pan, A. J. Weinheimer, C. Chemel
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2016)