Article
Materials Science, Multidisciplinary
Yongyan Hu, Yifan Lei, Xiuliang Liu, Ronggui Yang
Summary: This study demonstrates the use of multi-layer copper micromesh to enhance the heat transfer performance of liquid film boiling in spray cooling. The results show that the micromesh structure and spray flow rate have synergistic effects on liquid supply and bubble escape.
MATERIALS TODAY PHYSICS
(2022)
Article
Thermodynamics
J. B. Schmidt, I. V. Roisman, C. Tropea, J. Hussong
Summary: This study focuses on the heat flux during the cooling process of a hot substrate using an impacting monodisperse drop train. The temperature inside the substrate is measured with high temporal and spatial resolution using thermocouples. Additionally, a new analytical model has been developed to describe and predict the transient cooling and temperature of a semi-infinite body by the impacting drop train, assuming a single point heat sink on the surface. The experimental data show good agreement with the theoretical predictions for various drop train frequencies.
EXPERIMENTAL THERMAL AND FLUID SCIENCE
(2023)
Article
Thermodynamics
Saeed Vahidifar, Seyedhadi Banihashemi
Summary: Researchers have conducted numerous studies on active and passive methods to improve thermal performance and increase heat transfer in internal flows. Different geometries and configurations of turbulators have been proposed for optimal performance in heat exchangers. However, there is limited research on turbulators with equal obstruction inside the tube and aerodynamic geometry. This study investigates the effect of stimulating the boundary layer of the internal flow on heat transfer and flow characteristics, using a pipe with ring-shaped turbulators and equal blocking area.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Emma M. Veley, Karen A. Thole
Summary: This paper investigates the cooling performance of different cross-sectional shapes of cooling channels and finds that the triangle - vertex up shape has a 14% improvement in overall effectiveness compared to other shapes.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Tao Yang, Wei Zhang, Jianyou Wang, Chuang Liu, Mengzhou Yuan
Summary: This study numerically investigated heat transfer enhancement and surface temperature non-uniformity (STNU) improvement of spray cooling using CFD. Results showed different optimal spray heights for heat transfer and STNU, leading to the development of two methods to enhance heat transfer and reduce STNU. Spray-array jets cooling was found to minimize STNU compared to traditional spray cooling cases. Various liquid film microscopic characteristics and droplet distribution were identified as key factors influencing heat transfer and STNU.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Thermodynamics
X. L. Zhong, K. C. Chan, S. C. Fu, L. Q. Wang, Christopher Y. H. Chao
Summary: Piezoelectric fan cooling is receiving increased attention for its compact size and high energy efficiency. This study investigates the impact of fan location and channel configuration on heat transfer performance. By adjusting the fan position, a higher streamwise velocity is achieved, leading to improved heat transfer. Inserting a fan into the channel results in a 55% enhancement of the Nusselt number compared to natural convection. Additionally, both expansion and contraction configurations enhance heat transfer, with the optimal configuration providing an additional 10% enhancement. Flow visualization and velocity measurements reveal that the contraction configuration boosts streamwise velocity and generates a jet flow pattern, while the expansion configuration promotes more vortices and spanwise mixing.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
S. Muthukrishnan, X. Tan, V Srinivasan
Summary: Spray impingement heat transfer experiments were conducted to assess the role of surface roughness on heat transfer performance. The results show that heat transfer performance is better for length scales in the 5-10 μm range than for sub-micron scales. Surfaces with bigger pillar size and larger spacing exhibit greater heat transfer coefficient values due to higher permeability for wicking flow.
APPLIED THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Haojie Xu, Junfeng Wang, Bin Li, Kai Yu, Jiameng Tian, Dongbao Wang, Wei Zhang
Summary: The heat transfer performance of electrospray cooling has been experimentally investigated with different spray modes, showing that droplet size decreases and spray velocity increases with higher applied voltage. As the spray mode transitions to cone-jet/multi-jet modes, the nucleate boiling region is extended and the critical heat flux increases. Electrospray cooling significantly enhances cooling capacity by precise control under certain conditions.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
P. Kotrbacek, M. Chabicovsky, J. Kominek, O. Resl, H. Bellerova
Summary: This paper investigates the influence of water temperature on spray cooling and provides correlations and transformation functions to extend existing correlations. It fills the research gap by presenting generalized results.
APPLIED THERMAL ENGINEERING
(2022)
Article
Engineering, Chemical
Naveen Kushwaha, Vimal Kumar
Summary: This paper numerically predicts the two-phase boiling phenomenon of water around the heated surface of a helically coiled tube at a critical pressure (P-sat = 21.9 MPa). Results show that curvature and orientation play a critical role in fluid dynamics, heat transfer, and vapor volume production.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Thermodynamics
Haiwang Li, Meng Wang, Ruquan You, Zhi Tao
Summary: In this study, a method for separating the contribution of radiative heat flow from the total heat flow in turbine blades with different film-cooling structures is proposed. The effect of film hole angle on the proportion of radiative heat flow is studied, and the radiative heat flow is estimated accurately. Computational fluid dynamics (CFD) simulation data verify the reliability of the method, showing that the radiative heat flow curve decreases as the fourth power of temperature. Future research should focus on the impact of thermal radiation in blade heat transfer design.
APPLIED THERMAL ENGINEERING
(2023)
Article
Mechanics
Chanwoo Park, Kwangjin Jang, Bhavana Joshi, Ashwin Khadka, Ali Aldalbahi, Mostafizur Rahaman, Alexander L. Yarin, Sam S. Yoon
Summary: Device cooling schemes using textured surfaces augmented by highly porous materials were developed to reduce the temperature of solar panels and solar air heaters, while maintaining their radiative heat. The introduction of highly porous iron carboxylate framework, MIL-100(Fe), significantly reduced the surface temperature during air and mist cooling. The proposed coatings promoted rapid evaporative cooling and increased the Leidenfrost limit.
Article
Thermodynamics
Pengfei Liu, Ranjith Kandasamy, Jin Yao Ho, Huicheng Feng, Teck Neng Wong
Summary: The study revealed that adding Rhamnolipid can significantly enhance heat transfer during spray cooling, while adding Sophorolipid can lead to a decrease in heat transfer. All three surfactants can enhance heat transfer during nucleate boiling, with biosurfactants performing better than the conventional surfactant.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Wei Du, Lei Luo, Yinghou Jiao, Songtao Wang, Xingchen Li, Cong Chen
Summary: This paper numerically investigates the influence of film cooling hole locations and blowing ratios on thermal performance. The study found that different locations of film cooling holes result in different flow and cooling effects. The film cooling hole disrupts the boundary layer and enhances heat exchange in the latticework duct.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Review
Green & Sustainable Science & Technology
Mohamed H. Mousa, Nenad Miljkovic, Kashif Nawaz
Summary: Enhancing heat transfer between fluids and walls is crucial for improving performance. By utilizing features that enhance heat transfer, equipment size can be reduced, costs minimized, and safety risks mitigated.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
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)