Article
Thermodynamics
Harshal S. Raut, Amitabh Bhattacharya, Atul Sharma
Summary: The study uses Direct Numerical Simulations to investigate the impact of base plate oscillations on nucleate boiling heat transfer. The results show the existence of a lock-on regime where the frequency of bubble departure synchronizes with the frequency of plate oscillation. Increasing oscillation amplitude enhances this lock-on effect and also increases the average Nusselt number by around 22%.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Computer Science, Interdisciplinary Applications
Loric Torres, Annafederica Urbano, Catherine Colin, Sebastien Tanguy
Summary: Numerical simulations of Nucleate Boiling have gained increasing attention in recent years. Further studies are required on the modeling of heat flux near the contact line. This paper proposes a coupling methodology between a micro-region theoretical model and a larger scale DNS solver to investigate the quantitative effect of the micro-region on bubble growth in Nucleate Boiling.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
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
Harshal S. Raut, Amitabh Bhattacharya, Atul Sharma
Summary: This work presents Direct Numerical Simulations to study the effect of base plate oscillations on nucleate boiling heat transfer at low superheat, in the isolated bubble regime, under zero gravity conditions. The proposed technique of asymmetric periodic motion of the base plate sustains nucleate boiling in zero gravity and has potential applications for heat transfer enhancement in space.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Jinming Zhang, Maimuna Rafique, Wei Ding, Igor A. Bolotnov, Uwe Hampel
Summary: Recently, experiments have shown the formation of a thin liquid microlayer underneath a growing bubble in nucleate boiling. This study focuses on investigating the dynamics of the microlayer and its effect on microlayer evaporation. Through numerical simulations, a fully resolved microlayer underneath a growing bubble driven by the local temperature gradient in nucleate boiling is reproduced. The results are validated against experimental observations and a model, revealing the quasi-steady process of microlayer formation and the significant role of microlayer evaporation in nucleate boiling modeling.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Takuya Adachi, Xinyu Chang, Hiroki Nagai
Summary: Loop heat pipes (LHPs) are efficient two-phase heat transfer devices widely used in spacecraft thermal control. A new steady-state model was developed to investigate the effect of nucleate boiling in the evaporator core, and the conditions under which nucleate boiling does not occur were identified.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Nuclear Science & Technology
Sihong He, Bing Tan, Jingtan Chen, Wei Deng, Jiyun Zhao
Summary: This study investigates the boiling processes on a hybrid wettability micropillar structured surface and reveals that the synergistic effect of wettability and surface structure can enhance nucleate boiling. Additionally, hydrophobic nanopillar structured surfaces further enhance nucleate boiling. It highlights the importance of surface design for improving energy conversion and thermal management efficiency.
ANNALS OF NUCLEAR ENERGY
(2023)
Article
Thermodynamics
Jinming Zhang, Maimuna Rafique, Wei Ding, Igor A. Bolotnov, Uwe Hampel
Summary: Recent experimental studies have shown that surface engineering has great potential in enhancing nucleate boiling heat transfer. However, the underlying mechanism, particularly the role of microlayer evaporation, remains unclear. In this study, Direct Numerical Simulations (DNS) were used to investigate the heat transfer from microlayer evaporation underneath a growing bubble on micro-pillar arrayed surfaces. The effects of micro-pillar structures on the microlayer profile and heat transfer performance were systematically studied and analyzed. The results reveal three distinct microlayer morphologies associated with micro-pillar structures, and suggest a strategy for the design of micro-pillar arrayed surfaces to achieve optimal heat transfer performance.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2023)
Article
Chemistry, Physical
Chang Guo, Can Ji, Yalong Kong, Zhigang Liu, Lin Guo, Yawei Yang
Summary: In this study, a modified molecular dynamics simulation was used to investigate bubble nucleation on rough nanostructured substrates with different liquid-solid interactions. The results show that as the contact angle decreases, the nucleation rate increases due to more thermal energy being transferred to the liquid on better-wetting surfaces. The rough profiles of the substrate provide nanogrooves that enhance initial bubble nucleation and improve thermal energy transfer efficiency. Additionally, atomic energies are calculated and adopted to explain the formation of bubble nuclei on various wetting substrates. The simulation results are expected to guide surface design in state-of-the-art thermal management systems, such as surface wettability and nanoscale surface patterns.
Article
Thermodynamics
Harshal S. Raut, Amitabh Bhattacharya, Atul Sharma
Summary: This study characterizes nucleate boiling heat transfer in ethanol from a single nucle-ation site on a horizontal base plate in the presence of a solid copper torus, either stationary or subjected to forced oscillations. Enhanced Nusselt number is observed due to thinning of the thermal boundary layer under the torus and thickening near the bubble, especially during torus oscillations.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Engineering, Chemical
Tianjiao Wang, Xingsen Mu, Shengqiang Shen, Gangtao Liang
Summary: In this study, the sessile droplet boiling on a micropillar array surface in the nucleate boiling regime is comprehensively investigated using a three-dimensional lattice Boltzmann model. The effects of micro-pillar size on bubble behaviors inside droplet are discussed in detail.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Mojtaba Edalatpour, Camryn L. Colon, Jonathan B. Boreyko
Summary: By using ice pellets instead of water droplets, nucleate boiling can be maintained up to 500 ℃, as the tandem phase-change processes at the solid-liquid and liquid-vapor interfaces dampen the rate of vapor generation.
Article
Thermodynamics
Ning Qiu, Yimin Xuan, Jiangang Li, Qiang Li
Summary: This study aims to investigate the micro-layer evaporation mechanism at high pressure and establish a method to calculate it. Through the validation of two single bubble growing cases and a high-pressure pool boiling experiment, the accuracy of the initial micro-layer thickness model under high pressure environment is confirmed. The results demonstrate that micro-layer evaporation contributes to about 70% of the vapor in nucleate pool boiling.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Zirui Li, Zhenyu Wang, Wei Shao, Qun Cao, Zheng Cui
Summary: The nucleate boiling process on rectangular grooved surfaces with varying aspect ratio is studied through molecular dynamics simulation. The rectangular grooves can significantly accelerate the initial bubble nucleation time and delay the transition from bubble nucleation to film boiling. However, when the groove width is extremely narrow, bubbles cannot be generated first due to the limitation of geometric structure and low potential energy region inside the groove.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
Article
Mechanics
Alireza Salehi, Saeed Mortazavi, Mohamadamin Amini
Summary: In this paper, a direct numerical simulation of saturated nucleate pool boiling is performed using a hybrid front tracking method. The obtained results are in excellent agreement with previous analytical, numerical, and experimental studies. The effects of different fluids and dimensionless parameters on the heat transfer performance of the boiling surface are investigated, and the mechanisms and patterns of nucleate pool boiling are revealed.
Article
Thermodynamics
Jaewon Lee, Gihun Son
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2016)
Article
Thermodynamics
Donghyun Kim, Gihun Son, Sungil Kim
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2016)
Article
Engineering, Mechanical
Donghyun Kim, Gihun Son, Sungil Kim
JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
(2016)
Article
Engineering, Mechanical
Hochan Hwang, Gihun Son
JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
(2016)
Article
Thermodynamics
Hochan Hwang, Gihun Son
HEAT TRANSFER ENGINEERING
(2018)
Article
Thermodynamics
Hanjun Yu, Gihun Son, Woosup Shim
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2017)
Article
Thermodynamics
Jaewon Lee, Gihun Son
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2017)
Article
Thermodynamics
Moonhyeok Choi, Gihun Son, Woosup Shim
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2017)
Article
Engineering, Mechanical
Sungwook Cho, Gihun Son, Sungil Kim
JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
(2017)
Article
Engineering, Mechanical
Seongeun Hong, Gihun Son
JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
(2017)
Article
Thermodynamics
Jaewon Lee, Gihun Son
NUMERICAL HEAT TRANSFER PART A-APPLICATIONS
(2017)
Article
Thermodynamics
Sungwook Cho, Gihun Son
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2018)
Article
Thermodynamics
Hyunseung Lee, Gihun Son
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2018)
Article
Engineering, Mechanical
Jaewon Lee, Gihun Son
JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
(2018)
Article
Computer Science, Interdisciplinary Applications
Moonhyeok Choi, Gihun Son, Woosup Shim
COMPUTERS & FLUIDS
(2017)
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)