Quang-Thai Nguyen^1,2,#, Duong Ngoc Hai^3,4,#, The-Duc Nguyen^1,3,4,*, Van-Tu Nguyen^2,*, Jinyul Hwang², Warn-Gyu Park²

CMES-Computer Modeling in Engineering & Sciences, Vol.145, No.3, pp. 3433-3452, 2025, DOI:10.32604/cmes.2025.070570 - 23 December 2025

Abstract This study presents a numerical analysis of the effects of a rigid flat wall with oscillating motion on the pressure wave propagation during a single spherical cavitation bubble collapse at different initial bubble positions. Different nondimensional distances S = 0.8, 0.9, 1.0, 1.1, 1.2 and 1.3 were considered to investigate the effects of initial in-phase and out-of-phase oscillations of the flat wall. Numerical simulations of cavitation bubble collapse near an oscillating wall were conducted using a compressible two-phase flow model. This model incorporated the Volume of Fluid (VOF) interface-sharpening technique on a general curvilinear moving… More > Graphic Abstract

Hojun Moon, Donghyun You^*

CMES-Computer Modeling in Engineering & Sciences, Vol.145, No.1, pp. 367-390, 2025, DOI:10.32604/cmes.2025.071648 - 30 October 2025

Abstract A numerical method is presented to simulate bubble–particle interaction phenomena in particle-laden flows. The bubble surface is represented in an Eulerian framework by a volume-of-fluid (VOF) method, while particle motions are predicted in a Lagrangian framework. Different frameworks for describing bubble surfaces and particles make it difficult to predict the exact locations of collisions between bubbles and particles. An effective bubble, defined as having a larger diameter than the actual bubble represented by the VOF method, is introduced to predict the collision locations. Once the collision locations are determined, the attachment of particles to the More >

Minki Kim¹, Jenny Jyoung Lee^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.145, No.1, pp. 345-366, 2025, DOI:10.32604/cmes.2025.070524 - 30 October 2025

Abstract Spherical bubble oscillations are widely used to model cavitation phenomena in biomedical and naval hydrodynamic systems. During collapse, a sudden increase in surrounding pressure initiates the collapse of a cavitation bubble, followed by a rebound driven by the high internal gas pressure. While the ideal gas equation of state (EOS) is commonly used to describe the internal pressure and temperature of the bubble, it is limited in its capacity to capture molecular-level effects under highly compressed conditions. In the present study, we employ non-ideal EOS for the gas (the van der Waals EOS and its… More >

Yizhong Wu^1,2, Changliang Han^1,2,*, Jianquan Xu^1,2, Long Ying^1,2, Kang Wang^1,2

Frontiers in Heat and Mass Transfer, Vol.23, No.4, pp. 1103-1128, 2025, DOI:10.32604/fhmt.2025.068181 - 29 August 2025

Abstract Bubble column reactors fitted with tube bundles (BCR TB) belong to common heat transfer equipment in the field of chemical engineering, yet the complicated thermal-hydraulics performance of BCR TB has not been deeply revealed. To fill this gap, the present study proposes a novel variable bubble size modeling approach based on the Euler-Euler two-fluid framework, which is coupled with the population balance model considering comprehensive interphase forces. On the basis of verifying numerical reliability using experimental data, the mechanism of bubble swarm flow around the tube bundle and the effects of gas sparger configurations on… More > Graphic Abstract

Zongyu Jie^1,2, Chao Dang^1,2,*, Qingliang Meng ^3,4

Frontiers in Heat and Mass Transfer, Vol.23, No.4, pp. 1053-1089, 2025, DOI:10.32604/fhmt.2025.066792 - 29 August 2025

Abstract With the increasing miniaturization of systems and surging demand for power density, accurate prediction and control of two-phase flow pressure drop have become a core challenge restricting the performance of microchannel heat exchangers. Pressure drop, a critical hydraulic characteristic, serves as both a natural constraint for cooling systems and determines the power required to pump the working fluid through microchannels. This paper reviews the characteristics, prediction models, and optimization measures of two-phase flow pressure drop for low-boiling-point working fluids in microchannels. It systematically analyzes key influencing factors such as fluid physical properties, operating conditions, channel… More >

Roasi A. Flayh^*, Ayser Muneer Flayh

Energy Engineering, Vol.122, No.7, pp. 2801-2818, 2025, DOI:10.32604/ee.2025.062916 - 27 June 2025

Abstract Double pipe heat exchangers (DPHEs) are normally utilized in various manufacturing uses owing to their simple design and low maintenance requirements. For that, performance enhancement by improved heat transfer is ongoing. Air injections are a good strategy for enhancing the thermal performance of the DPHE. In the present work, the influence of air bubble injection in a DPHE was experimentally investigated, and the system’s hydrothermal performance improvement parameters were evaluated. Two modes were designed, manufactured, and used to conduct the experiments. The first mode was conducted with no air injection, named a single phase mode,… More >

Zhi Yang^1,2, Xiaohui Zhang^1,2,*, Xinting Tong³, Yutang Zhao⁴, Teng Xia^1,2, Hua Wang^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1133-1150, 2025, DOI:10.32604/fdmp.2025.061737 - 30 May 2025

Abstract In bottom-blown copper smelting processes, oxygen-enriched air is typically injected into the melt through a lance, generating bubbles that ascend and agitate the melt, enhancing mass, momentum, and heat transfer within the furnace. The melt’s viscosity, which varies across reaction stages, and the operating conditions influence bubble size and dynamics. This study investigates the interplay between melt viscosity and bubble diameter on bubble motion using numerical simulations and experiments. In particular, the volume of fluid (VOF) method and Ω-identification technique were employed to analyze bubble velocity, deformation, trajectories, and wake characteristics. The results showed that More >

Shuaijie Jiang¹, Zechen Zhou¹, Xiuli Wang¹, Wei Xu², Wenzhuo Guo¹, Qingjiang Xiang^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.3, pp. 471-491, 2025, DOI:10.32604/fdmp.2025.059878 - 01 April 2025

Abstract In nature, cavitation bubbles typically appear in clusters, engaging in interactions that create a variety of dynamic motion patterns. To better understand the behavior of multiple bubble collapses and the mechanisms of inter-bubble interaction, this study employs molecular dynamics simulation combined with a coarse-grained force field. By focusing on collapse morphology, local density, and pressure, it elucidates how the number and arrangement of bubbles influence the collapse process. The mechanisms behind inter-bubble interactions are also considered. The findings indicate that the collapse speed of unbounded bubbles located in lateral regions is greater than that of More >

Pengcheng Cai^1,2, Teng Li³, Jianxin Xu^1,2,*, Xiaobo Li³, Zhiqiang Li^1,2, Zhiwen Xu³, Hua Wang^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.2, pp. 325-349, 2025, DOI:10.32604/fdmp.2024.057496 - 06 March 2025

Abstract In modern engineering, enhancing boiling heat transfer efficiency is crucial for optimizing energy use and several industrial processes involving different types of materials. This study explores the enhancement of pool boiling heat transfer potentially induced by combining perforated copper particles on a heated surface with a sodium dodecyl sulfate (SDS) surfactant in saturated deionized water. Experiments were conducted at standard atmospheric pressure, with heat flux ranging from 20 to 100 kW/m². The heating surface, positioned below the layer of freely moving copper beads, allowed the particle layer to shift due to liquid convection and steam More > Graphic Abstract

Naoyuki Nomura^1,*, Mingqi Dong¹, Zhenxing Zhou¹, Weiwei Zhou¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.31, No.4, pp. 1-1, 2024, DOI:10.32604/icces.2024.012381

Abstract Laser powder bed fusion (L-PBF) exhibits many technological opportunities for producing high-performance metallic parts with tailored architectures. However, fabrication of suitable composite powders possessing good flowability, controllable particle size and distribution is a currently prerequisite and main challenge. In this work, two novel techniques, namely freeze-dry pulsated orifice ejection method (FD-POEM) [1] and ultrafine bubble (UFB)-assisted heteroagglomeration [2], have been developed to fabricate uniform composite powders. By taking MoSiBTiC alloy powders as an example, the working principle of FD-POEM process was firstly illustrated. The spherical FD-POEM particles were consisted of typical mesh structures induced by… More >