Mingzhe Huang, Mi Xiao^*, Liang Gao, Mian Zhou, Wei Sha, Jinhao Zhang

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 2479-2505, 2024, DOI:10.32604/cmes.2023.045735

Abstract Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio. In this paper, a full-scale isogeometric topology optimization (ITO) method based on Kirchhoff–Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is proposed. This method utilizes high-order continuous nonuniform rational B-splines (NURBS) as basis functions for Kirchhoff–Love shell elements. The geometric and analysis models of thin shells are unified by isogeometric analysis (IGA) to avoid geometric approximation error and improve computational accuracy. The topological configurations of thin-shell structures are described by constructing the effective density field on the control… More >

Samsudin Anis^1,*, Deni Fajar Fitriyana¹, Aldias Bahatmaka¹, Muhammad Choirul Anwar¹, Arsyad Zanadin Ramadhan¹, Fajar Chairul Anam¹, Raffanel Adi Permana¹, Ahmad Jazilussurur Hakim², Natalino Fonseca Da Silva Guterres³, Mateus De Sousa Da Silva³

Journal of Renewable Materials, Vol.12, No.2, pp. 381-396, 2024, DOI:10.32604/jrm.2023.047128

Abstract Indonesia is one of the largest coconut-producing countries in the world. The utilization of coconut shell waste into briquettes will increase the selling value and become a great export opportunity. However, the effect of adhesives on the quality of coconut shell charcoal briquettes made using screw extruder machine has not been widely studied. This study aims to determine the effect of adhesive type on the quality of coconut shell charcoal briquettes. The process of fabricating briquettes in this study included crushing, mixing, blending, pressing, and drying. In the mixing process, 3 types of adhesives were used, namely tapioca flour (Briquette_1),… More > Graphic Abstract

Juanjuan Wang^*, Jiangping Nan, Yanan Wang

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2761-2775, 2023, DOI:10.32604/fdmp.2023.021175

Abstract The main objective of this study is the technical optimization of a Shell-and-Tube Heat Exchanger (STHE). In order to do so, a simulation model is introduced that takes into account the related gas-phase circulation. Then, simulation verification experiments are designed in order to validate the model. The results show that the temperature field undergoes strong variations in time when an inlet wind speed of 6 m/s is considered, while the heat transfer error reaches a minimum of 5.1%. For an inlet velocity of 9 m/s, the heat transfer drops to the lowest point, while the heat transfer error reaches a… More >

Jin Han¹, Qi Zhang^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09848

Abstract In this paper, we extend the Reissner-Mindlin shell theory based on peridynamics method proposed in [1] to the stiffened plate and explore its application to engineering problems, several examples are given to verify its effectiveness in the dynamic analysis. The coupling method is used in this paper to model the stiffened plate. The plate and the stiffener are treated as two independent shell to calculate the velocity and acceleration respectively, then the interaction between two parts of the stiffened plate is added at the coupling particle to satisfy the continuity condition. The non-local peridynamics theory of solids provides an integral… More >

Zhijian Zhou¹, Jie Yan^1,*, Xinxiang Du¹, Qiulin Xu¹, Zijun Wu², Jinlan Yang³, Xitong Fang¹, Qiuling Zhong², Qiaoguang Li^1,*

Journal of Renewable Materials, Vol.11, No.9, pp. 3501-3515, 2023, DOI:10.32604/jrm.2023.027852

Abstract Iron-pillared bentonite (FB) was prepared by Fe(III) modified bentonite, and then the composites (FB-OS) were prepared by iron-pillared bentonite and oyster shell powder. The composites were characterized by FTIR, SEM, TGA, and EDS, and the phosphorus removal test was carried out. The results showed that FB-OS contained a large amount of CaO. Its structure was compact, but there were gaps in it. The maximum bending stress and compressive strength were 43.7 N and 0.927 MPa, respectively. The phosphorus removal test showed that the phosphorus removal rate of FB-OS was more than 90%, and measured the maximum adsorption capacity was 48.31… More > Graphic Abstract

Xin Wang^1,3, Ying Yan^1,3, Hongmei Ji^1,3,*, Xiaowu Li^1,2,*

Journal of Renewable Materials, Vol.11, No.8, pp. 3297-3308, 2023, DOI:10.32604/jrm.2023.027066

Abstract As an essential renewable mineral resource, mollusk shells can be used as handicrafts, building materials, adsorbents, etc. However, there are few reports on the wear resistance of their structures. The Vicker’s hardness and friction, and wear resistance of different microstructures in mollusk shells were comparatively studied in the present work. The hardness of prismatic structures is lower than that of cross-lamellar and nacreous structures. However, the experimental results of sliding tests indicate that the prismatic structure exhibits the best anti-wear ability compared with foliated, crossed-lamellar, and nacreous structures. The anti-wear and hardness do not present a positive correlation, as the… More > Graphic Abstract

Marwah Subhi Attallah, Reem Alaa Mohammed^*, Ruaa Haitham Abdel-Rahim

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.10, pp. 2449-2469, 2023, DOI:10.32604/fdmp.2023.027750

Abstract This study aims to evaluate the erosion behavior and the hardness of hybrid composites made of varying amounts of coconut shells, walnut shells, and carbon fibers dispersed in a polyester matrix. MINITAB (L16) Taguchi experiments were used to determine the optimal combination of parameters. In particular, an erosion device consisting of a motor with a constant flow rate of 45 L/min, a pump with a diameter of 40 mm, a nozzle with a diameter of 5 mm, and a tank made of “perspex glass” 55 cm long, 30 cm tall, and 25 cm wide was used. The tests were conducted by varying the sample-to-nozzle distance, the… More > Graphic Abstract

Yalin Li^1,*, Lei Liu¹, Wenbao Huang¹, Junpu Xie², Zhaoxia Song¹, Shuna Guo¹, Enci Wang¹

Journal of Renewable Materials, Vol.11, No.7, pp. 3001-3023, 2023, DOI:10.32604/jrm.2023.026604

Abstract To achieve optimal recovery and value-added utilisation of cellulose in peanut shells, the cellulose in peanut shells was first extracted using the sodium hydroxide-sodium chlorite method. Then, cellulose hydrogel was prepared by graft copolymerisation using N, N’-methylenebisacrylamide as the cross-linking agent, sodium persulfate as the initiator, and acrylic acid as the monomer. Orthogonal optimisation experiments were designed to obtain optimal process parameters for hydrogel preparation with the cellulose dosage of 0.40 g, initiator dosage of 0.20 g, polymerisation temperature of 70°C, cross-linking agent of 0.25 g, and monomer dosage of 3.0 mL. The effect of initiator dosage on hydrogel synthesis was… More > Graphic Abstract

Pengda Li, Chao Xu, Zhirong Liao^* , Xing Ju, Feng Ye

Frontiers in Heat and Mass Transfer, Vol.15, pp. 1-10, 2020, DOI:10.5098/hmt.15.10

Abstract This study numerically investigates the charging and discharging processes of a three-stages cascaded latent heat thermal energy storage unit using three molten salts as the phase change materials (PCMs). Each stage of the unit is a vertical shell-and-tube heat exchanger, whose shell side is filled with the PCM and air. The liquid fractions, temperatures, and accumulated thermal energy of the PCMs during the fully charging and discharging processes, as well as the effects of the HTF inlet temperature, are analyzed. The results show that lower melting temperature of the PCM causes faster charging rate and more released heat in the… More >

Xiaoyong Gu^*, Guohe Jiang, Yang Wo, Biwen Chen

Frontiers in Heat and Mass Transfer, Vol.15, pp. 1-8, 2020, DOI:10.5098/hmt.15.3

Abstract The heat transfer characteristics of propylene glycol-water (PG-W) mixture with different concentrations in shell side of spiral wound heat exchanger (SWHE) with different geometric parameters were studied numerically. Experiment was carried out and the average difference between the simulated results and the experimental results was 5.3%. The simulation results show that heat transfer coefficient increases with the increase of center core diameter and longitudinal spacing of tubes, but decreases with the increase of tube outer diameter. The center core diameter and tube outer diameter have greater effects on heat transfer performances at higher concentration. Economic index was established and found… More >