Article
Mechanics
Claudiu Patrascu, Corneliu Balan
Summary: This study focuses on the capillary-wave field generated by a liquid jet impinging on a liquid reservoir. It shows that a slight increase in viscosity leads to rapid suppression of wave-like behavior and proposes a simple dependence on the combined Weber-Deborah number for the dimensionless damping coefficient. The experimental results are in good qualitative agreement with the theoretical predictions.
Article
Mechanics
Tianhong Tu, Shaowen Chen, Yuchen Shi, Weihang Li
Summary: In this study, the flow mechanisms and heat transfer characteristics of a sweeping jet on a confined concave surface were investigated using numerical simulations. The results showed that the sweeping jet exhibited better heat transfer performance compared to the circular jet at higher Reynolds numbers and narrower target spacings. The flow details inside the flow field were effectively correlated with the heat transfer characteristics of the target surface. Furthermore, the topology and three-dimensional vortex structure inside the confined channel were remodeled to provide theoretical support for subsequent applications.
Article
Engineering, Environmental
Zhong-Bo Sun, Hai -Long Liao, Li-Hua Wang, Lan Jiang, Xin Zhang, Bao-Ju Wang, Guang-Wen Chu, Yong Luo
Summary: The flow and breakage behaviors of two liquid jets impacting on stainless steel wire mesh were studied using high-speed photography. The impacts resulted in the formation of liquid jets and further breakage into daughter droplets. The impinging angle, liquid initial velocity, mesh number, and liquid jet diameter were found to affect the flow and breakage behaviors. For water-n-hexane jets, a liquid sheet was formed and could undergo marginal or internal breakup. This study provides a theoretical basis for mass transfer enhancement and reactor design in liquid-liquid systems.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Jie Tan, Yufeng Guo, Wanlin Guo
Summary: The spreading of water nanodroplets on solid surfaces after impinging has been systematically studied using large-scale molecular dynamics simulations. It was found that the spreading rates of nanodroplets initially increase and then decrease with increasing diameter, with the highest spreading rates observed at diameters of 17-19 nm. This is due to the combined effect of the strongest interfacial and surface interactions within water molecules. The results also revealed the nonmonotonic characteristics of spreading velocity, interface work of adhesion, and surface tension with nanodroplet diameter.
Article
Computer Science, Interdisciplinary Applications
F. -J. Granados-Ortiz, J. Ortega-Casanova, C. -H. Lai
Summary: This paper presents a probabilistic uncertainty analysis on computational heat transfer, indicating that the simulated system is not significantly sensitive to stochastic variations of input parameters. Additionally, nonlinear regression models for stochastic velocity and turbulent profiles for pipe nozzles are provided.
ENGINEERING WITH COMPUTERS
(2022)
Article
Multidisciplinary Sciences
Sanghoo Park, Wonho Choe, Hyungyu Lee, Joo Young Park, Jinwoo Kim, Se Youn Moon, Uros Cvelbar
Summary: This study investigates the impact of gas jets on a water surface and the stabilizing effect of weakly ionized gas on cavities. Experimental results demonstrate that plasma bullets generated by weakly ionized gas can exert more force on the water surface through electrohydrodynamic flow, leading to cavity expansion without destabilization.
Article
Mechanics
Zi-wei Hou, Ning Li, Xiao-long Huang, Can Li, Hai-cheng Lv, Yang Kang, Chun-sheng Weng
Summary: This study theoretically and experimentally investigates the pressure evolution of detonation waves penetrating into water. The results show that the pressure rise ratios between the detonation and transmitted wave have a certain range and can be influenced by different factors. The experimental results are in good agreement with the theoretical values, highlighting the importance of this research for underwater detonation engines.
Article
Mechanics
Hyunduk Seo, Goran Marjanovic, S. Balachandar, Kyung Chun Kim
Summary: The effect of slip velocity in a bubbly jet with various bubble slip ratios was studied using direct numerical simulations. It was found that a high slip ratio results in a rigid, narrower bubbly jet core region, where the turbulent kinetic energy is conserved along the centerline but does not diffuse towards the ambient region.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Dong Kim, Daniel Schanz, Matteo Novara, Hyunduk Seo, Youngwoo Kim, Andreas Schroeder, Kyung Chun Kim
Summary: This study introduces a method to simultaneously measure time-resolved three-dimensional velocity fields of dispersed and continuous phases of a turbulent bubbly jet at a low void fraction using Lagrangian particle tracking (LPT) velocimetry with the Shake-The-Box algorithm. The results show that streamwise vortex structures in the continuous phase of the bubbly jet are mainly generated by rising bubbles, and the slip velocity in the radial direction increases linearly. Experimental verification is provided for the classical assumption of self-similarity with Gaussian profiles for fluid velocity and bubble concentration.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Physics, Applied
Tlegen Kamidollayev, Juan Pablo Trelles
Summary: This study investigates the interaction between an argon plasma jet and water using a 3D time-dependent computational model. The results suggest that higher jet velocities lead to enhanced transport of reactive species across the plasma-water interface.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Mohammad Saeed Emami, Masoud Haghshenasfard, Reza Zarghami, Roohollah Sadeghi, Mohsen Nasr Esfahany
Summary: This study experimentally determined the nucleation and growth kinetics of loratadine and simulated the anti-solvent precipitation process to obtain ultrafine loratadine nanoparticles. The effect of supersaturation on nucleation and growth rates was found to be significant. The study also assessed size-dependent particle growth and the effect of turbulence aggregation on simulated particle size distribution. The findings contribute to understanding the formation of loratadine nanoparticles and optimizing their production process.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Mechanics
Daehyun Choi, Jungwon Byun, Hyungmin Park
Summary: This study investigates the atomization of a water column by a gas jet flow issued from a two-stage annular nozzle. By varying the nozzle geometry, the momentum flux ratio of the upper and lower jets, and the water flow rate, the atomization process is analyzed into four regimes. It is found that the lower jet drives the atomization in the bulk atomization regime, but it is forced to occur earlier by the stronger upper jet in the droplet atomization regime. Interestingly, the size of the atomized droplets remains unaffected by the momentum flux ratio of upper to lower jets. The atomization process is governed by the Rayleigh-Taylor instability, and the estimated droplet size agrees well with the measurement.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Shahram Karami, Julio Soria
Summary: This study uses large-eddy simulations to investigate the influence of nozzle external geometry on upstream-travelling waves in under-expanded supersonic jets. It is found that the external geometry significantly affects the first-order statistics and leads to multiple peaks in the energy spectra at distinct frequencies. Different forms of upstream-travelling wavepackets contribute to the receptivity process with their contributions and strength altered by the change of the external geometry of the nozzle.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Alessandro Bongarzone, Arnaud Bertsch, Philippe Renaud, Francois Gallaire
Summary: The study investigates self-sustained oscillations induced by the interaction of two impinging jets in microfluidic devices, confirming a predominantly two-dimensional physical mechanism. Utilizing global stability analysis and weakly nonlinear theory, the research reveals hysteresis in the system within a certain aspect ratio range. The Kelvin-Helmholtz instability is identified as the main candidate for the observed oscillations in fluidic devices.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Assem Elzaabalawy, Shaker A. Meguid
Summary: This study investigates the mechanisms associated with the impingement of supercooled water droplets on superhydrophobic and icephobic surfaces using numerical simulations. The model predictions are in excellent agreement with experimental findings, and the results are crucial for anti-icing applications.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2022)