Article
Energy & Fuels
Prashant Agrawal, Gary G. Wells, Rodrigo Ledesma-Aguilar, Glen McHale, Khellil Sefiane
Summary: The article discusses a thin-film boiling engine where power output can be controlled by manipulating the position of the rotor over the substrate in a heated state. This new approach offers potential for applications in virtually frictionless engines in extreme environments, particularly at microscales or for space and planetary exploration, with propulsion outputs almost 4 times higher than traditional methods.
Article
Thermodynamics
Swapan Paruya, Jyoti Bhati, Farheen Akhtar
Summary: An improved numerical model was developed to simulate the dynamics of bubble shape and departure in nucleate pool boiling. The model was validated through comparisons with experimental and literature results. Bubble shape was found to be influenced by superheat and Bond number, with direct numerical integration of Young-Laplace working well for spherical bubbles and an approximate analytical solution working better for non-spherical bubbles.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Sandipan Banerjee, Yang Liu, Mark Sussman, Yongsheng Lian
Summary: This paper proposes a new approach to simulate the evaporation and depletion process of the liquid micro layer in nucleate boiling. By estimating the micro layer thickness and calculating the temperature gradient integration, the simulation of bubble growth rate and heat flux is achieved and verified against experimental results.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Zhenyu Liu, Zeyu Liu, Runkeng Liu
Summary: Surface wettability and structure are important factors affecting thermal transport at the solid-liquid interface at the nano scale. This study used non-equilibrium molecular dynamics to investigate the boiling behavior of nano thin liquid argon film on heterogeneous wetting surfaces. The results showed that a lower hydrophobic area fraction favored bubble formation and the ring-patterned surface was more conducive to nucleate boiling compared to the stripe-patterned surface. The nano-structure also played a significant role in enhancing boiling heat transfer.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Yujie Chen, Shuqi Jin, Bo Yu, Kong Ling, Dongliang Sun, Wei Zhang, Kaituo Jiao, Wenquan Tao
Summary: This study proposes a method for investigating the subcooled flow boiling heat transfer in a rectangular channel by considering the microlayer, conjugated heat transfer, nucleation site density, and liquid-vapor interface. Results indicate that microlayer evaporation contributes significantly to bubble volume and heat dissipation.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Tsutomu Ubara, Katsumi Sugimoto, Hitoshi Asano
Summary: This study experimentally investigated the liquid film thickness and heat transfer coefficients on an inclined plate and found that the film thickness increases under nucleate boiling conditions, and the average thickness increases with the heat flux.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Chemistry, Physical
Ben Chu, Cheng Fang, Feiyu Zheng, Weizheng Cheng, Ruitong Wang, Wanli Zhang, Jinran Tao, Lei Huai, Peng Tao, Chengyi Song, Wen Shang, Benwei Fu, Tao Deng
Summary: Graphene-based films can enhance heat transfer capacity by modifying surface structure and chemistry, but current preparation methods are complex and require additional equipment. The SBISA method developed in this study offers a simple way to generate graphene-based films, leading to significant improvements in boiling performance.
MATERIALS TODAY ENERGY
(2021)
Article
Mechanics
Alok Kumar, Prasad Kangude, Atul Srivastava
Summary: This study investigates the interaction modes between adjacent vapor bubbles on a high wettability surface during subcooled nucleate pool boiling. The results show that the parameters such as subcooling level, spacing between the bubbles, and supplied heat flux have a significant impact on the bubble dynamics and microlayer depletion.
Article
Mechanics
Alok Kumar, Prasad Kangude, Atul Srivastava
Summary: This study investigates the interaction between two adjacent vapor bubbles during subcooled nucleate pool boiling on a high wettability surface. The results show that the interaction affects the dynamic parameters of the bubbles and the microlayer dynamics. The study identifies three modes of interaction and reveals that the heat flux, subcooling level, and spacing between the bubbles have a strong impact on the interaction mechanism.
Article
Thermodynamics
Ayush Kumar Dixit, Rupak Kumar, Arup Kumar Das
Summary: In this study, the film boiling of liquid nitrogen on liquid water is numerically investigated. The characteristics of film boiling and the effects of disturbances on it are studied. The temperature, velocity field, and evaporation rate of liquid nitrogen are obtained. The numerical results are validated with experimental studies and compared with previous research.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Xiuliang Liu, Qifan Zou, Ronggui Yang
Summary: In this paper, a theoretical model for bubble nucleation in liquid film boiling is developed, considering transient heat conduction, evaporation at the liquid-vapor interface, and superheat requirement for bubble nucleus stability. The study establishes the ONB criterion and active microcavity size range, comparing them with pool and flow boiling.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Mohd Moiz, Sai Raja Gopal Vadlamudi, Atul Srivastava
Summary: This study investigates the possible mechanism(s) of bubble growth on hydrophobic surfaces under nucleate flow boiling conditions. It has been found that even on low wettability surfaces, the formation of microlayer can occur under the influence of bulk flow inertia. Observations made through thin-film interferograms confirmed the formation of microlayer on hydrophobic surfaces, and it was also found that the rate of growth of dry patch is higher on hydrophobic surfaces compared to hydrophilic substrates.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Peng Ju, Takashi Hibiki
Summary: A comprehensive understanding of annular flow characteristics is essential for improving the efficiency and safety of petroleum and natural gas pipelines, as well as heat transfer equipment. Liquid film characteristics and wave characteristics play crucial roles in heat and mass transfer in annular flows. This paper reviews previous studies and prediction models for these parameters and examines their predictive capability using existing databases. The effects of channel geometry, pressure, and heating state on these characteristics are considered, and the importance of heating state in wave velocity prediction is highlighted.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Jiahua Li, Lin Chen, Fengchu Jin, Yuannan Zhang, Qingyang Wang, Haizhen Xian, Jun Lin
Summary: The use of micro/nano-porous membranes enhances boiling heat transfer, with ultrahigh heat flux being achieved in thin film boiling experiments. The nanoporous membrane plays a crucial role in distributing liquid and serving as a heating surface. Active regulation schemes were proposed to improve performance, with nonuniform membranes showing differences in critical heat flux and responses to electric power increase.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Materials Science, Multidisciplinary
Pengkun Li, Xiuliang Liu, Qifan Zou, Xinlei Zhang, Ronggui Yang
Summary: High-power electronic devices present challenges and opportunities for two-phase cooling technologies. Capillary-driven liquid film boiling, combining capillary evaporation and nucleate boiling, is a promising cooling method. However, the mechanism of liquid film boiling is not well understood. In this study, a model is developed to predict the incipience of liquid film boiling, and experiments validate the model's effectiveness.
MATERIALS TODAY PHYSICS
(2023)
Article
Mechanics
Nicolas Bouvet, Savannah S. Wessies, Eric D. Link, Stephen A. Fink
Summary: This study presents a framework to characterize firebrand flows and compare exposure through the use of a measurement device and data processing methods. The ability to perform exposure comparisons and recognize combustion states is demonstrated.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
P. Botticini, G. Lavalle, D. Picchi, P. Poesio
Summary: This study investigates the gravity-driven liquid layer problem on an inclined plate, taking into account the variable density of the fluid. The study examines the influence of density variation on the formulation of a depth-averaged model and the role of compressibility in long-wave interfacial instability.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Jean-Paul Caltagirone
Summary: This article introduces a method for modeling capillary flows on a surface or at the interface of two fluids. The method involves handling the two components of capillary acceleration using the divergence and curl of surface normal. The proposed formulation is characterized by directional curvature based on dihedral angle, intrinsic anisotropic surface tension per unit mass, and introduction of capillary potential.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Qi-Teng Zheng, Chun-Bai-Xue Yang, Shi-Jin Feng, Yu-Chen Song, Yong Zhao, Yu-Lin Wu
Summary: This paper proposes a new two-phase partitioning boundary model to accurately predict the drying process of a porous medium from saturated to unsaturated conditions. The model is validated through laboratory soil drying tests and the study also investigates the effects of air-water interfacial area and water retention parameters on the drying process.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Alexandra Metallinou Log, Morten Hammer, Svend Tollak Munkejord
Summary: Flashing flow is commonly found in industrial systems and accurate flashing models are essential for the design of safe and efficient CO2 transportation systems. We propose a homogeneous flashing model that takes into account the physical phenomena of phase change. The model is fitted using CO2 pipe depressurization data and we find that the same model parameters can be applied for different cases.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Q. Tan, S. A. Hosseini, A. Seidel-Morgenstern, D. Thevenin, H. Lorenz
Summary: The possible impact of temperature differences during crystal growth is investigated in this study. A numerical model is developed to simulate the crystallization dynamics of (S)-mandelic acid, taking into account temperature effects. The study shows that the heat generation at the crystal interface has only a small effect on the surrounding temperature field.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Hideki Murakawa, Sana Maeda, Sven Eckert
Summary: This study investigates the behavior of bubbles in a liquid metal under the influence of a magnetic field, particularly bubble chains. The results show that increasing the magnetic field strength suppresses the oscillations of the bubbles and concentrates their crossing positions in a specific area. Applying these findings to numerical models can further optimize continuous casting processes.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Johanna Potyka, Kathrin Schulte
Summary: This paper presents an advanced Volume of Fluid (VOF) method for performing three-dimensional Direct Numerical Simulations (DNS) of the interaction of two immiscible fluids in a gaseous environment with large topology changes. The method includes efficient reconstruction of phase boundaries near the triple line using a Piecewise Linear Interface Calculation (PLIC) method and enhanced surface force modeling with the Continuous Surface Stress (CSS) model. Implementation of these methods in the multi-phase flow solver Free Surface 3D (FS3D) yielded successful validation. The simulations provide valuable insights into the collision process and can support future modeling of immiscible liquid interaction.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Martin Rohde, Sebastian Burgmann, Uwe Janoske
Summary: This study investigates the effect of superimposing an incident flow and two-dimensional vibration on the critical air flow velocity required for the detachment of a droplet. The results show that oscillatory excitation at specific frequencies can significantly reduce the critical velocity for droplet detachment.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Tea-Woo Kim, Baehyun Min
Summary: Liquid-gas two-phase slug flow is a complex flow pattern in energy systems, and accurately predicting slug liquid holdup is crucial for system design and operation. Existing HLLS models have limited applicability due to a lack of physical basis. This study proposes a new dimensionless number SP and correlates it with HLLS data, resulting in a unified HLLS correlation that agrees closely with experimental data.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Christian Lieber, Stephan Autenrieth, Kai-Yannic Schoenewolf, Amy Lebanoff, Rainer Koch, Sterling Smith, Paul Schlinger, Hans-Joerg Bauer
Summary: The observation of acoustically levitated droplets offers great potential for studying their evaporation characteristics. The main objective of this study is to present an experimental setup that minimizes the disturbing effects of the levitation technique in order to investigate convective heat and mass transfer during droplet evaporation.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Facundo Cabrera-Booman, Nicolas Plihon, Mickael Bourgoin
Summary: The settling behavior of individual spheres in a quiescent fluid was experimentally studied. The mean trajectory angle with the vertical showed complex behavior as the parameters Gamma and Ga varied. The transition from planar to non-planar trajectories and the emergence of semi-helical trajectories were observed, especially for denser spheres.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Hongbin Wang, Hanwen Luo, Jinbiao Xiong
Summary: This article introduces an iterative screening method for closure models in nucleate boiling flow simulation, and demonstrates its accuracy through experiments.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Alexandra Metallinou Log, Morten Hammer, Han Deng, Anders Austegard, Armin Hafner, Svend Tollak Munkejord
Summary: This study investigates the rapid depressurization of liquid CO2 and compares the predictions of different models. It is found that higher temperatures result in shorter relaxation times.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Mechanics
Rizwan Zahoor, Sasa Bajt, Bozidar Sarler
Summary: This numerical study evaluates the jet characteristics of non-Newtonian power-law fluids in a gas dynamic virtual nozzle. The results show that shear-thinning fluids result in thicker, longer, and slower jets compared to shear-thickening fluids. Additionally, a dripping-jetting phase diagram of the nozzle is obtained by varying the power law index, gas, and liquid flow rates.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)