Article
Environmental Sciences
Raheleh Faridi-Majidi, Faezeh Norouz, Safieh Boroumand, Seyed Nasrollah Tabatabaei, Reza Faridi-Majidi
Summary: This study examines the effects of different decontamination techniques on the integrity and functionality of nanofiber-based N95 masks. The results show that decontamination with 70% ethanol can cause significant unfavorable changes in filtration efficiency and microstructure. On the other hand, autoclave and UV light do not have a significant impact on filtration efficiency or microstructure.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Chemistry, Physical
Zixiao Guo, Jing Sun, Xinzhuang Fan, Tianshou Zhao
Summary: Designing flow fields with enhanced convection is crucial for improving battery performance. This study presents a numerically modeled convection-enhanced flow field, which is achieved by redesigning the flow path to enhance mass transport. Key geometric parameters and flowing patterns are investigated. The results show that adjusting the channel fraction and number can achieve a more uniform reactant distribution but increase pumping work. Additionally, seven novel flow path designs with enhanced convection are proposed by tailoring rotary methods. The optimized flow field demonstrates higher pump-based voltage efficiency in a vanadium redox flow battery.
JOURNAL OF POWER SOURCES
(2023)
Article
Materials Science, Multidisciplinary
H. R. Li, Y. Ruan
Summary: The unique vortex-shaped microstructure formed in Al70Ag20Ge10 alloy droplets during microgravity solidification was driven by prominent Marangoni motion. The flow pattern was preserved during the rapid growth of metastable Ag2Al dendrites, and was weakened with the decrease of droplet size, leading to the formation of anomalous eutectics. In comparison, solidification under gravity condition resulted in different flow patterns and phase selections in the alloy.
MATERIALS & DESIGN
(2021)
Article
Thermodynamics
F. Koca
Summary: This study numerically investigated the turbulent fluid flow and heat transfer through a backward-facing step connected to a corrugated wall. It was found that the channel surface with a specific geometry achieved the highest heat transfer under certain Reynolds numbers.
JOURNAL OF ENGINEERING THERMOPHYSICS
(2022)
Article
Mechanics
Xufeng Shen, Xin Li
Summary: Viscous flow resistance is dominated by viscous friction between fluid and wall. The flow resistance characteristic curve, represented as the Δp-Q curve, depends on inherent characteristic variables. This paper proposes a new design of variable viscous flow resistance using a rotating slit flow channel to achieve the purpose of changing the Δp-Q curve. Experimental verification shows the significant roles of rotational inertia gradient and viscous gradient terms in governing the radial pressure gradient.
Article
Engineering, Chemical
Antai Liu, Linhai Cheng, Changqi Yan, Haifeng Gu, Zhaoming Meng
Summary: This paper presents a visualization investigation on the characteristic parameters and pressure drop of slug flow in a narrow rectangular channel. The study reveals a linear relationship between the slug bubble velocity and the two-phase mixture velocity, and provides fitting equations for laminar and turbulent flow zones. A new correlation for predicting the liquid film thickness is proposed and validated. Additionally, the relationship between slug length and liquid/gas flow rates is examined, and existing correlations for pressure drop are summarized and evaluated.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2022)
Article
Thermodynamics
Kai Tang, Yanpei Huang, Guiping Lin, Yuandong Guo, Jinyin Huang, Haimiao Lin, Hongxing Zhang, Qi Yang, Jianyin Miao
Summary: This study designed and fabricated a manifold microchannel heat sink to enhance the heat dissipation capability of high-heat-flux hotspots. Ammonia with excellent thermophysical properties was selected as the working fluid, and its thermal-hydraulic characteristics were evaluated. The effects of flow rate, heat flux, saturation temperature, and inlet conditions on the heat sink were investigated through experiments. The results showed that under high-subcooled inlet conditions, the thermal resistance decreased and pressure drop increased with increasing flow rate. Under near-saturated inlet conditions, jet impingement and microchannel cooling were identified as the dominant heat transfer mechanisms.
APPLIED THERMAL ENGINEERING
(2023)
Article
Chemistry, Physical
Hyunkyu Moon, Davis J. McGregor, Nenad Miljkovic, William P. King
Summary: This study presents the design, fabrication, and characterization of a three-dimensional heat exchanger with tube-in-tube architecture using genetic algorithm design and metal additive manufacturing. Through careful thermal hydraulic experiments, the heat exchanger demonstrated high power density and specific power, outperforming commercially available heat exchangers.
Article
Energy & Fuels
Weiqi Fu, Jing Yu, Yang Xiao, Chenglai Wang, Bingxiang Huang, Baojiang Sun
Summary: A novel model is proposed to predict the pressure drop of hydrate slurry bubbly flow based on the energy dissipation theory. The reliability of the model is validated using published data.
Article
Thermodynamics
Pankaj Srivastava, Ruchitkumar Ishwarlal Patel, Anupam Dewan
Summary: A comparative study was conducted on the flow and thermal characteristics in a double-layered microchannel with bifurcation, showing that the bifurcation plates reduce the overall thermal resistance but increase pressure drop and pumping power. Nusselt number is higher in parallel-flow than counter-flow, but the difference is greater at low Re values and diminishes with increasing flow rate. Counter-flow offers a more uniform temperature distribution essential for thermal system reliability.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Acoustics
Amol Gode, Ketan Madane, Vivek V. Ranade
Summary: The design parameters such as aspect ratio of the vortex chamber, number of tangential inlets, and shape of the device significantly influence the flow characteristics and cavitation in vortex-based hydrodynamic cavitation devices. Experimental validation of computational studies showed that an aspect ratio of six is optimal. The performance of devices with single and multiple inlets is comparable at the same pressure drop. Simplification of the device configuration for scale-up does not significantly affect cavitation performance.
ULTRASONICS SONOCHEMISTRY
(2023)
Article
Thermodynamics
Arjun Jayakumar, A. Mani
Summary: A nonintrusive technique based on air-coupled ultrasonic transducer was used to study the behavior of falling film over metal foam layered horizontal tubes. The application of metal foam significantly enhanced the heat transfer efficiency of the falling film.
JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME
(2022)
Article
Thermodynamics
Mohammad Jafari, Amir Farajollahi, Heshmatollah Gazori
Summary: The study reveals that the swirl generator significantly enhances the heat transfer rate while also increasing the pressure drop, especially at lower Reynolds numbers.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Mechanics
Ke Wang, Zhuo Cheng, Na Wu, Qi Zhang, Li Liu
Summary: Previous studies have shown that the flooding of the falling film around the Taylor bubble is due to the transition from slug flow to churn flow, which is related to the generation and evolution of large waves. This study establishes theoretical models based on the Kelvin-Helmholtz instability of the falling film and kinematic analysis of the interfacial wave to reveal the mechanism of the slug/churn transition. The proposed model is verified to have satisfactory predicting accuracy and the effects of pipe diameter and system pressure on the transition are discussed.
Article
Chemistry, Multidisciplinary
Yongchao Rao, Shuli Wang, Lijun Li
Summary: This study conducted a numerical simulation to investigate the gas-liquid two-phase spiral annular flow pattern and its conversion law in a horizontal tube with twist tape by spiral on-way. It identified three main flow patterns and identified the main factor affecting the existence of the gas phase. Additionally, it discovered a new flow pattern compared to the local spiral flow pattern of the short twisted band.