Khalilallah Memarzadeh¹, Hamed Kazemipoor^1,*, Mohammad Fallah¹, Babak Farhang Moghaddam²

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.2, pp. 1275-1304, 2024, DOI:10.32604/cmes.2024.050306 - 27 September 2024

Abstract Motivated by a critical issue of airline planning process, this paper addresses a new two-stage scenario-based robust optimization in operational airline planning to cope with uncertainty and possible flight disruptions. Following the route network scheme and generated flight timetables, aircraft maintenance routing and crew scheduling are critical factors in airline planning and operations cost management. This study considers the simultaneous assignment of aircraft fleet and crew to the scheduled flight while satisfying a set of operational constraints, rules, and regulations. Considering multiple locations for airline maintenance and crew bases, we solve the problem of integrated… More > Graphic Abstract

Xueyan Lin^1,#, Mingtao Wu^2,#, Guodong Li^1,*, Nan Guo³, Lidan Mei¹

Structural Durability & Health Monitoring, Vol.18, No.6, pp. 805-833, 2024, DOI:10.32604/sdhm.2024.051033 - 20 September 2024

Abstract In this paper, a new type of bamboo scrimber column embedded with steel bars (rebars) was proposed, and the compression performance was improved by pre-embedding rebars during the preparation of the columns. The effects of the slenderness ratio and the reinforcement ratio on the axial compression performance of reinforced bamboo scrimber columns were studied by axial compression tests on 28 specimens. The results showed that the increase in the slenderness ratio had a significant negative effect on the axial compression performance of the columns. When the slenderness ratio increased from 19.63 to 51.96, the failure… More >

Bo Zhang¹, Yunxie Huang², Peilin Cui², Zhiguo Wang¹, Duo Ding¹, Zhenhai Pan³, Zhenyu Liu^2,*

Frontiers in Heat and Mass Transfer, Vol.22, No.4, pp. 997-1016, 2024, DOI:10.32604/fhmt.2024.053592 - 30 August 2024

Abstract The high surface area of porous media enhances its efficacy for evaporative cooling, however, the evaporation of pure substances often encounters issues including local overheating and unstable heat transfer. To address these challenges, a volume of fluid (VOF) model integrated with a species transport model was developed to predict the evaporation processes of ternary mixtures (water, glycerol, and 1,2-propylene glycol) in porous ceramics in this study. It reveals that the synergistic effects of thermal conduction and convective heat transfer significantly influence the mixtures evaporation, causing the fluctuations in evaporation rates. The obtained result shows a More >

Hongzhang Wang¹, Jing Guo¹, Shanjun Yang¹, Chaoheng Cheng², Jing Chen^3,*, Zhihao Chen³

Structural Durability & Health Monitoring, Vol.18, No.2, pp. 181-196, 2024, DOI:10.32604/sdhm.2024.044628 - 22 March 2024

Abstract Pitting corrosion is harmful during bridge construction, which will lead to uneven roughness of steel surfaces and reduce the thickness of steel. Hence, the effect of pitting corrosion on the mechanical properties of cold-formed thin-walled steel stub columns is studied, and the empirical formulas are established through regression fitting to predict the ultimate load of web and flange under pitting corrosion. In detail, the failure modes and load-displacement curves of specimens with different locations, area ratios, and depths are obtained through a large number of non-linear finite element analysis. As for the specimens with pitting… More > Graphic Abstract

Oulfa Harrat^1,*, Yazid Hadidane¹, S. M. Anas^2,*, Nadhim Hamah Sor^3,4, Ahmed Farouk Deifalla⁵, Paul O. Awoyera⁶, Nadia Gouider¹

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 3435-3465, 2024, DOI:10.32604/cmes.2023.044950 - 11 March 2024

Abstract Given their numerous functional and architectural benefits, such as improved bearing capacity and increased resistance to elastic instability modes, cold-formed steel (CFS) built-up sections have become increasingly developed and used in recent years, particularly in the construction industry. This paper presents an analytical and numerical study of assembled CFS two single channel-shaped columns with different slenderness and configurations (back-to-back, face-to-face, and box). These columns were joined by double-row rivets for the back-to-back and box configurations, whereas they were welded together for the face-to-face design. The built-up columns were filled with ordinary concrete of good strength.… More > Graphic Abstract

Ayat N. Mahmood¹, Amer A. Abdulrahman¹, Laith S. Sabri^1,*, Abbas J. Sultan¹, Hasan Shakir Majdi², Muthanna H. Al-Dahhan³

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.2, pp. 239-256, 2024, DOI:10.32604/fdmp.2023.028015 - 14 December 2023

Abstract Hydrodynamics characterization in terms of flow regime behavior is a crucial task to enhance the design of bubble column reactors and scaling up related methodologies. This review presents recent studies on the typical flow regimes established in bubble columns. Some effort is also provided to introduce relevant definitions pertaining to this field, namely, that of “void fraction” and related (local, chordal, cross-sectional and volumetric) variants. Experimental studies involving different parameters that affect design and operating conditions are also discussed in detail. In the second part of the review, the attention is shifted to cases with 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… More >

Dalia S. Makki¹, Hasan Sh. Majdi², Amer A. Abdulrahman¹, Abbas J. Sultan^1,3,*, Zahraa W. Hasan¹, Laith S. Sabri^1,3, Bashar J. Kadhim¹, Muthanna H. Al-Dahhan³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.10, pp. 2613-2637, 2023, DOI:10.32604/fdmp.2023.028081 - 25 June 2023

Abstract Bubble and slurry bubble column reactors (BCRs/SBCRs) are used for various chemical, biochemical, and petrochemical applications. They have several operational and maintenance advantages, including excellent heat and mass transfer rates, simplicity, and low operating and maintenance cost. Typically, a catalyst is present in addition to biochemical processes where microorganisms are used to produce industrially valuable bio-products. Since most applications involve complicated gas-liquid, gas-liquid-solid, and exothermic processes, the BCR/SBCR must be equipped with heat-exchanging tubes to dissipate heat and control the reactor’s overall performance. In this review, past and very recent experimental and numerical investigations on More >

Liang Yang^*, Tianle Xi, Zhixing Wang

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1585-1608, 2023, DOI:10.32604/fdmp.2023.024987 - 30 January 2023

Abstract The VOF method is used to simulate the dynamics of a droplet interacting with a structure consisting of an array of microcolumns mounted on a flat surface. Such a specific configuration is intended to mimic the typical properties of lotus leaves, which typically display regularly arranged micron-scale papillary structures. After setting the initial velocity of the simulated droplet on the basis of practical considerations, an analysis is conducted about the effect of the characteristic size of the microstructure on the apparent contact angle. The pressure variation in the microstructure caves is also examined. The simulation More >

Xiaofeng Zhang¹, Lisheng Luo^2,*, Youfu Sun¹, Xinyue Cui², Yongqiang Zhang²

Journal of Renewable Materials, Vol.11, No.4, pp. 2033-2054, 2023, DOI:10.32604/jrm.2022.023651 - 01 December 2022

Abstract Considering the glulam beam-column connection form and the number of bolts, monotonic loading test and finite element analysis was carried out on 9 connection specimens in 3 groups to study the rotational performance and failure mode of the connection. The test results revealed that compared with U-shaped connectors, T-shaped connectors can effectively improve the ductility of connections, and the increase in the number of bolts can reduce the initial stiffness and ductility of connections. By theoretical analysis, formulas for calculating the initial stiffness and ultimate moment of connections were deduced. Subsequently, the moment-rotation theoretical model More > Graphic Abstract