Karema A. Hamad^*, Yasser A. Mahmood

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2863-2875, 2023, DOI:10.32604/fdmp.2023.029049

Abstract The cooling of a (pebble bed) spent fuel in a high-temperature gas-cooled reactor (HTGR) is adversely affected by an increase in the temperature of the used gas (air). To investigate this problem, a configuration consisting of three copper spheres arranged in tandem subjected to a forced mist flow inside a cylindrical channel is considered. The heat transfer coefficients and related variations as a function of Reynolds number are investigated accordingly. The experimental results show that when compared to those with only airflow, the heat transfer coefficient of the spherical elements with mist flow (j = 112 kg/m² hr, Re =… More >

Hongfei Ye^1,*, Chenguang Yin¹, Jian Wang¹, Yonggang Zheng¹, Hongwu Zhang¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09741

Abstract The wetting behavior is ubiquitous in natural phenomenon as well as engineering application. As an intrinsic property of solid surface, the wettability with a controllable gradient has been an attractive issue with a wide application in various fields, including microfluidic devices, self-driven transport, biotechnologies, etc. Generally, it often requires elaborate design of microstructure or its response under the electrical, thermal, optical, pH stimuli, etc. However, the relevant complex underlying mechanism makes it difficult to construct quantitative relations between the wettability and the external field for the fine design. In this work, based on the bilayer two-dimensional materials, a simple controlling… More >

Fujian Zhang¹, Xiang Gao¹, Zhongqiang Zhang^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.4, pp. 1-1, 2023, DOI:10.32604/icces.2023.09169

Abstract Biological features such as the bumps on the back of desert beetles and the spikes of cacti enable the directional transport of water droplets, creating conditions for their survival in nature. Inspired by the interesting natural phenomenon, a novel design of nanopillared surface with a gradient density of structural pillar matrix covered by a monolayer graphene is proposed to realize ultrafast self-driving of water droplets. The droplet can move spontaneously at ultrahigh speed of 75.7 m/s (272.52 km/h) from sparsest to densest regions of pillars while a wettability gradient is created by the gradient distribution density of pillar matrix relying… More >

Yue Hu¹, Lu-Wen Zhang^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.010595

Abstract Liquid accretion control plays a key role across a wide range of industrial applications, such as anti-icing, power generation, sewage treatment, water desalination, and energy harvesting. In condensation system, durable dropwise condensation of saturated vapor for heat transfer and energy saving in extensive industrial applications. While numerous superhydrophobic surfaces can promote steam condensation, maintaining discrete microdroplets on surfaces without the formation of a flooded filmwise condensation at high subcooling remains challenging. Here, we report the development of carbon nanotube arrayembedded hierarchical composite surfaces that enable ultra-durable dropwise condensation under a wide range of subcooling temperatures (∆T_sub = 8 K–38 K),… More >

Yunyun Song¹, Xu Zhang¹, Jialei Yang¹, Zhongqiang Zhang^1,*, Guanggui Cheng¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.09916

Abstract Although floating oil with large particle sizes can easily be separated from water by membrane separation methods, tiny oil droplets with tremendously small volume force and density gradient at oil-water interfaces within water lead to barriers of oil-water separation. Consequently, tiny oil droplets remain in the water, resulting in energy waste, environmental pollution and biological health hazard. Traditional super-wetting membranes with extremely small pore sizes were easily blocked during the oil-water separation process. Inspired by the cactus and rice leaf, we developed a superhydrophobic-superoleophilic surface with conical micro-arrays to realize ultrafast adsorption of tiny oil droplets within the water. The… More >

Yuhang Wang^1,2, Gaojin Li^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.2, pp. 1-2, 2023, DOI:10.32604/icces.2023.09895

Abstract The chemically active droplets, which converts the chemical energy into a localized fluid flow at the interfaces by generating a concentration gradients of surfactant, can realize self-propulsion with complex trajectories and have been widely studied to mimic the swimming behavior of micro-organisms. In reality, the motion of chemically active droplets is influenced by a combination of diffusiophoresis and Marangoni effect under concentration gradients of surfactant. However, the interaction between these two effects has been only studied for a drop under the constraint of the axial-symmetric motion. To understand the hydrodynamics of the unconstraint motion, we consider a two-dimensional drop model… More >

AlemKarima^a,*, Sahel Djamel^b , Nemdili Ali^c, Ameur Houari^d

Frontiers in Heat and Mass Transfer, Vol.10, pp. 1-7, 2018, DOI:10.5098/hmt.10.27

Abstract In the present paper, the effects of a new baffle design on the efficiency of a tubular heat exchanger are numerically investigated. It concerns butterfly baffles inserted in a cylindrical tube heat exchanger. We focus on the influence of the shape of baffles, the space between baffles (pitch ratio, PR) and the baffle size (i.e. the blockage ratio, BR) on the heat transfer and flow characteristics. Three geometrical configurations with different PRs are realized (PR = 1, 2 and 4) and five others with different blockage ratios (BR = 0.1, 0.2, 0.3, 0.4 and 0.5). The investigations are achieved for… More >

Jiaxing Sun¹, Lili Ji^1,*, Qianrui He¹, Ran Li¹, Xiaoyue Xia², Yaning Wang¹, Yi Yang², Lu Cai³, Jian Guo²

Journal of Renewable Materials, Vol.11, No.8, pp. 3227-3243, 2023, DOI:10.32604/jrm.2023.027160

Abstract

In this study, a novel absorpent (MSAR600°C) with a hydrophobic surface and hierarchical porous structure for the removal of kitchen oil was facilely fabricated from the macroalgae, laver (Porphyra haitanensis) by incorporating high-temperature carbonization and alkyl polyglucosides (APG) and rhamnolipid (RL) surfactants modification. The characterization results showed MSAR600°C possessed a louts-leaf-like papillae microstructure with high contact angle (137.5°), abundant porous structure with high specific surface area (23.4 m²/g), and various oxygen-containing functional groups (-OH, C=O, C-O). Batch adsorption experiments were conducted to investigate the effect of adsorption time, temperature, pH, and absorbent dose on kitchen oil adsorption performance. Then the… More > Graphic Abstract

Sibel Day^*, Nilüfer Koçak-Şahin

Phyton-International Journal of Experimental Botany, Vol.92, No.8, pp. 2461-2471, 2023, DOI:10.32604/phyton.2023.029920

Abstract Aromatic and medicinal plant species having small seeds have field emergence problems due to low nutrient supply. Therefore, Pimpinella anisum seeds were hydro and osmoprimed with 100 mM MgCl₂, CaCl₂, and ZnCl₂, for 2, 4, and 8 h each to compare their growth attributes during germination and seedling establishment stages. Nontreated seeds were used as control. Both hydro and osmo primed seeds were dried for 48 h before, they were sown in plastic trays in growth room conditions to see the impact of treatments on seedling emergence and growth. The maximum root length (12.90 cm), fresh weight (256.30 mg plant⁻¹),… More >

Mohammed Bourega^*, Ibrahim Kromba, Khadidja Fellah Arbi, Sofiane Soulimane

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.10, pp. 2471-2480, 2023, DOI:10.32604/fdmp.2023.028661

Abstract This study uses a T-junction to examine the effects of different parameters (velocity ratio, viscosity, contact angle, and channel size ratio) on the generation of microdroplets, related rate, and size. More specifically, numerical simulations are exploited to investigate situations with a velocity varying from 0.004 to 1.6 m/s for the continuous phase and from 0.004 to 0.8 m/s for the dispersed phase, viscosity ratios (0.668, 1, 6.689, 10, 66.899), contact angle 80° < θ < 270° and four different canal size ratios (1, 1.5, 2 and 4). The results show that canal size influences droplet size and the generation rate.… More > Graphic Abstract