Article
Engineering, Chemical
Ege Ertekin, John M. Kavanagh, David F. Fletcher, Dale D. McClure
Summary: This paper presents a model that accurately simulates the hydrodynamics of bubble columns and shows good agreement with experimental data. The study also takes into account the presence of surface-active compounds in industrial processes, providing computational predictions in line with experimental measurements. Furthermore, a dataset has been provided to facilitate validation work by others and identify areas for further research.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2021)
Article
Engineering, Environmental
Shanshan Long, Xiaogang Yang, Jie Yang, Martin Sommerfeld
Summary: The added mass stress and turbulent dispersion force have significant effects on the bubble dynamics and mass transfer in bubble column bubbly flow.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Mechanics
Y. Mezui, M. Obligado, A. Cartellier
Summary: This study revisits the hydrodynamics of bubble columns in the heterogeneous regime. By conducting experiments and analyzing data, the self-organization phenomenon in the heterogeneous regime and the applicability of velocity scaling under different conditions are confirmed. Furthermore, the importance of velocity scaling for coalescing media is discussed.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Vikash Pandey, Dhrubaditya Mitra, Prasad Perlekar
Summary: A direct numerical simulation study of buoyancy-driven bubbly flows in the presence of large-scale driving that generates turbulence reveals that increasing turbulence intensity leads to more curved bubble trajectories and decreased average rise velocity. The energy spectrum of the flow exhibits pseudo-turbulence scaling for small length scales and Kolmogorov scaling for larger scales. A scale-by-scale energy budget analysis helps understand the scaling behavior seen in the spectrum, with statistical properties consistent with experiments on turbulence modulation by air bubbles in water despite the weak buoyancy of the bubbles.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Chemical
Yuyun Bao, Ruiting Wang, Shugang Ma, Kaijie Wen, Zhengming Gao, Ziqi Cai
Summary: In this study, the mass transfer coefficient between a single bubble and the surrounding liquid in a flow chamber at elevated temperatures was experimentally measured and analyzed. The effects of liquid physical properties and molecular diffusion were considered, with the latter being the main factor. A modified correlation was proposed to describe the impact of gas phase partial pressure resulting from the change of liquid temperature on the mass transfer coefficient. The volumetric mass transfer coefficient of single bubbles in the flow chamber can be compared to that in a stirred tank, even at elevated temperatures and low stirring speeds.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Thermodynamics
Kota Fujiwara, Kohei Yoshida, Akiko Kaneko, Yutaka Abe
Summary: This study focuses on the aerosol transportation resulting from the flow field inside single bubbles in bubble columns. The dominant role of inertial force in aerosol transportation is revealed through measuring the aerosol mass transfer efficiency of a single bubble and developing a three-phase model. The study also conducts a parametric analysis of aerosols with different diameters to investigate the mass transportation phenomena.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Engineering, Environmental
Kai Zhang, Shuai Wang, Hanyu Jin, Yurong He
Summary: This research considers the importance of the bubble cloud in the mass transfer process and develops a mass transfer model based on clouded bubbles. Experimental results show that the proposed model provides better agreement with experimental data.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Chen Li, Yongli Ma, Mingyan Liu, Kaiyue Wang
Summary: In this study, PIV was used to investigate the flow fields in gas-liquid mini-bubble columns. It was found that the increase of superficial liquid velocity could change the trajectory and size of bubbles, and the terminal velocity of bubbles was influenced by bubble buoyancy and flow resistance, slightly increasing with bubble coalescence.
Article
Mechanics
Stephane Perrard, Alienor Riviere, Wouter Mostert, Luc Deike
Summary: In this study, the deformation modes and lifetime of a bubble in a turbulent flow are investigated through numerical simulations and theoretical analysis. Two temporal regimes are observed during the bubble deformation process, with the first regime driven by inertial forces and the second regime resulting from a balance between inertial forces and surface tension.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Daniel J. Ruth, Marlone Vernet, Stephane Perrard, Luc Deike
Summary: The study shows that the average rising speed of bubbles in liquid decreases with increasing turbulence intensity, following a specific proportional relationship. This is mainly due to the effects of nonlinear drag and the nearly isotropic behavior of the slip velocity on the mean rise speed.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Kazuki Maeda, Masanobu Date, Kazuyasu Sugiyama, Shu Takagi, Yoichiro Matsumoto
Summary: A series of experiments and modelling were conducted to study the interaction of a pair of spherical bubbles rising in a vertical channel. The results showed that bubbles take two preferential configurations depending on their mutual distance, which helps to elucidate the clustering mechanisms.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
D. Raciti, P. Brocca, A. Raudino, M. Corti
Summary: We present a new interferometric method to study the interactions between two gas bubbles in a liquid undergoing small-amplitude oscillations. The technique allows for accurate measurement of the amplitude, frequency, and phase of oscillation, as well as probing the interactions between the bubbles. This method is of great importance for understanding bubble interactions.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Alienor Riviere, Wouter Mostert, Stephane Perrard, Luc Deike
Summary: This study investigates the dynamics and statistics of bubble break-up in homogeneous and isotropic turbulence through direct numerical simulations, focusing on the influence of the Weber number on bubble break-up dynamics. The findings reveal that during the transition to stable conditions, bubble break-up occurs through both local and non-local production processes, resulting in a range of bubble sizes.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Mirko Gallo, Francesco Magaletti, Carlo Massimo Casciola
Summary: This study investigates the impact of solid walls on bubble formation in heterogeneous nucleation processes, exploring the direct effects of boundary conditions compliant with fluctuation-dissipation balance on nucleation.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Chemical
Chengxiang Li, Yizhou Cui, Xiaogang Shi, Jinsen Gao, Xingying Lan
Summary: This study evaluates the applicability and accuracy of three widely-used mass transfer models in the simulations of mass transfer in bubble columns. By comparing simulation results with experimental data, suggestions on choosing a proper mass transfer model are provided. The influence of bubble-induced turbulence and its different modeling approaches on different mass transfer models are also investigated.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Engineering, Environmental
Xin Feng, Chao Yang, Zai-Sha Mao, Jiacai Lu, Gretar Tryggvason
CHEMICAL ENGINEERING JOURNAL
(2019)
Article
Mechanics
Min Lu, Jiacai Lu, Ying Zhang, Gretar Tryggvason
Article
Thermodynamics
Huanxiong Xia, Jiacai Lu, Gretar Tryggvason
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2019)
Article
Mechanics
Min Lu, Jiacai Lu, Ying Zhang, Grtar Tryggvason
Article
Physics, Fluids & Plasmas
Jiacai Lu, Gretar Tryggvason
PHYSICAL REVIEW FLUIDS
(2019)
Article
Energy & Fuels
Alireza Mahdavi Nejad, Gretar Tryggvason
JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME
(2020)
Article
Mechanics
Xuebo Zheng, Jiacai Lu, Bofeng Bai, Gretar Tryggvason
Article
Mechanics
Zaheer Ahmed, Daulet Izbassarov, Jiacai Lu, Gretar Tryggvason, Metin Muradoglu, Outi Tammisola
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2020)
Article
Computer Science, Interdisciplinary Applications
T. Arrufat, M. Crialesi-Esposito, D. Fuster, Y. Ling, L. Malan, S. Pal, R. Scardovelli, G. Tryggvason, S. Zaleski
Summary: The study focuses on the computation of flows with large density contrasts, using a discretization of the Navier-Stokes equation and considering the impact of capillary forces on incompressible flows. Mass and momentum advection is done in a consistent manner, incorporating the Volume-of-Fluid method and Height-Function method, along with different volume fraction advection methods.
COMPUTERS & FLUIDS
(2021)
Article
Mechanics
Xianyang Chen, Jiacai Lu, Gretar Tryggvason
Summary: This study examines a process for coarsening or filtering fully resolved numerical solutions for incompressible multiphase flows while retaining a sharp interface. Different phases are identified using an index function and small flow scales are embedded in other phases by solving diffusion equations with modified coefficients. This approach results in solutions similar to filtered fully resolved fields, particularly for the Rayleigh-Taylor instability at early times.
Article
Mechanics
Xianyang Chen, Jiacai Lu, Stephane Zaleski, Gretar Tryggvason
Summary: This article reports a study that uses skeletonization to describe complex liquid droplet structures. By diffusing an index function and moving the interfaces accordingly, the skeleton of the droplet can be obtained, representing its basic topology. Various quantitative measures are also explored to characterize and distinguish the skeleton structures of the droplets.
Article
Physics, Fluids & Plasmas
Xianyang Chen, Jiacai Lu, Gretar Tryggvason
Summary: This study uses machine learning to develop closure terms for a coarse grained model of two-dimensional turbulent flow directly from coarse grained data, accurately predicting the time evolution of the flow field.
Proceedings Paper
Mathematical & Computational Biology
Gretar Tryggvason, Jiacai Lu
INTERNATIONAL CONFERENCE ON NUMERICAL ANALYSIS AND APPLIED MATHEMATICS ICNAAM 2019
(2020)
Article
Nanoscience & Nanotechnology
Zhiping Yuan, Huimin Hou, Liyu Dai, Xiaomin Wu, Gretar Tryggvason
ACS APPLIED MATERIALS & INTERFACES
(2020)
Article
Mechanics
Wenbin Li, Jiacai Lu, Gretar Tryggvason, Ying Zhang
Summary: The self-transport of droplets on discontinuous wetting gradient surfaces is influenced by surface roughness, affecting both the transport velocity and stability of motion.
Article
Thermodynamics
Mahsa Taghavi, Swapnil Sharma, Vemuri Balakotaiah
Summary: This study investigates the natural convection effects in the insulation layers of spherical storage tanks and their impact on the tanks' performance. The permeability and Rayleigh number of the insulation material are considered as key factors. The results show that as the Rayleigh number increases, new convective cells emerge and cause the cold boundary to approach the external hot boundary. In the case of large temperature differences, multiple solutions may coexist.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinyang Xu, Fangjun Hong, Chaoyang Zhang
Summary: This study introduces a self-induced jet impingement device for enhancing pool boiling performance in high power electronic cooling. Through visualization and parametric investigations, the effects of this device on pool boiling performance are studied, revealing the promotion of additional liquid supply and vapor exhausting. The flow rate of the liquid jet is found to positively impact boiling performance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Wenchao Ke, Yuan Liu, Fissha Biruke Teshome, Zhi Zeng
Summary: Underwater wet laser welding (UWLW) is a promising and labor-saving repair technique. A thermal multi-phase flow model was developed to study the heat transfer, fluid dynamics, and phase transitions during UWLW. The results show that UWLW creates a water keyhole, making the welding environment similar to in air laser welding.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Xingrong Lian, Lin Tian, Zengyao Li, Xinpeng Zhao
Summary: This study investigates the heat transfer mechanisms in natural fiber-derived porous structures and finds that thermal radiation has a significant impact on the thermal conductivity in low-density regions, while natural convection rarely occurs. Insulation materials derived from micron-sized natural fibers can achieve minimum thermal conductivity at specific densities. Strategies to lower the thermal conductivity include increasing porosity and incorporating nanoscale pores using nanosize fibers.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Yasir A. Malik, Kilian Koebschall, Stephan Bansmer, Cameron Tropea, Jeanette Hussong, Philippe Villedieu
Summary: Ice crystal icing is a significant hazard in aviation, and accurate modeling of sticking efficiency is essential. In this study, icing wind tunnel experiments were conducted to quantify the volumetric liquid water fraction, sticking efficiency, and maximum thickness of ice layers. Two measurement techniques, calorimetry and capacitive measurements, were used to measure the liquid water content and distribution in the ice layers. The experiments showed that increasing wet bulb temperatures and substrate heat flux significantly increased sticking efficiency and maximum ice layer thickness.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinqi Hu, Tongtong Geng, Kun Wang, Yuanhong Fan, Chunhua Min, Hsien Chin Su
Summary: This study experimentally examined the heat dissipation of vibrating fans and demonstrated its inherent mechanism through numerical simulation. The results showed that the flow fields induced by the vibrating blades exhibited pulsating features and formed large-scale and small-scale vortical structures, significantly improving heat dissipation. The study also identified the impacts of different blade structures and developed a trapezoidal-folding blade, which effectively reduced the maximum temperature of the heat source and alleviated high-temperature failure crisis.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Dan-Dan Su, Xiao-Bin Li, Hong-Na Zhang, Feng-Chen Li
Summary: The boiling heat transfer of low-boiling-point working fluid is a common heat dissipation technology in electronic equipment cooling. This study analyzed the interfacial boiling behavior of R134a under different conditions and found that factors such as the initial thickness of the liquid film, solid-liquid interaction force, and initial temperature significantly affect the boiling mode and thermal resistance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinyi Wu, Dongke Sun, Wei Chen, Zhenhua Chai
Summary: A unified lattice Boltzmann-phase field scheme is proposed to simulate dendrite growth of binary alloys in the presence of melt convection. The effects of various factors on the growth are investigated numerically, and the model is validated through comparisons and examinations.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Shaokun Ge, Ya Ni, Fubao Zhou, Wangzhaonan Shen, Jia Li, Fengqi Guo, Bobo Shi
Summary: This study investigated the temperature distribution of main cables in a suspension bridge during fire scenarios and proposed a prediction model for the maximum temperature of cables in different lane fires. The results showed that vehicle fires in the emergency lane posed a greater thermal threat to the cables.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Shuang-Ying Wu, Shi-Yao Zhou, Lan Xiao, Jia Luo
Summary: This paper investigates the two-phase flow and heat transfer characteristics of low-velocity jet impacting on a cylindrical surface. The study reveals that the heat transfer regimes are non-phase transition and nucleate boiling with the increase of heat transfer rate. The effects of jet impact height and outlet velocity on local surface temperatures are pronounced at the non-phase transition stage. The growth rates of heat transfer rate and liquid loss rate increase significantly from the non-phase transition to nucleate boiling stage.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Emad Hasani Malekshah, Wlodzimierz Wlodzimierz, Miros law Majkut
Summary: Cavitation has significant practical importance and can be controlled by air injection. This study investigates the natural to ventilated cavitation process around a hydrofoil through numerical and experimental methods. The results show that the location and rate of air injection have a meaningful impact on the characteristics of cavitation.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Feriel Yahiat, Pascale Bouvier, Antoine Beauvillier, Serge Russeil, Christophe Andre, Daniel Bougeard
Summary: This study explores the enhancement of mixing performance in laminar flow equipment by investigating the generation of chaotic advection using wall deformations in annular geometries. The findings demonstrate that the combined geometry can achieve perfect mixing at various Reynolds numbers.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Hui He, Ning Lyu, Caihua Liang, Feng Wang, Xiaosong Zhang
Summary: This study investigates the condensation, frosting, and defrosting processes on superhydrophobic surfaces with millimeter-scale structures. The results reveal that the structures can influence the growth and removal of frost crystals, with the bottom grooves creating a frost-free zone and conical edges promoting higher frost crystal heights. Two effective methods for defrosting are observed: hand-lifting the groove and airfoil retraction contraction on protruding structures. This research provides valuable insights into frost formation and defrosting on millimeter-structured superhydrophobic surfaces, with potential applications in anti-frost engineering.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Thiwanka Arepolage, Christophe Verdy, Thibaut Sylvestre, Aymeric Leray, Sebastien Euphrasie
Summary: This study developed two thermal concentrators, one with a 2D design of uniform thickness and another with a 3D design, using the coordinate transformation technique and metamaterials. By structuring the thermal conductor, the desired local density-heat capacity product and anisotropic thermal conductivities were achieved. The homogenized thermal conductivities were obtained from finite element simulations and cylindrical symmetry consideration. A 3D concentrator was fabricated using 3D metal printing and characterized using a thermal camera. Compared to devices that solely consider anisotropic conductivities, the time evolution characteristics of the metadevice designed with coordinate transformation were closer to those of an ideal concentrator.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Liangyuan Cheng, Qingyang Wang, Jinliang Xu
Summary: In this study, we investigated the supercritical heat transfer of CO2 in a horizontal tube with a diameter of 10.0 mm, covering a wide range of pressures, mass fluxes, and heat fluxes. The study revealed a non-monotonic increase in wall temperatures along the flow direction and observed both positive and negative wall temperature differences between the bottom and top tube. The findings were explained by the thermal conduction in the solid wall interacting with the stratified-wavy flow in the tube.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
