Seyed Ehsan Rafiee^*, M. M. Sadeghiazad

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-15, 2016, DOI:10.5098/hmt.7.13

Abstract The aim of this investigation is study on separation phenomenon inside a special vortex tube affected by structural and physical factors including; throttle diameter, nozzle number and injection pressure as well as the parametric optimization based on separation efficiency using experimental and 3D-CFD methods. The results show that convergent VT with Dth=5.5mm provides 30.01% and 20.04% higher cooling and heating effectiveness compared to basic model. As another result, the higher injection pressure, the higher cooling effectiveness. The cooling effectiveness improves (16.86%) with increase in slot number up to N=4, then decreases. The maximum disagreement between experimental and predicted values is… More >

A. Zoubir^a , R. Agounoun^a,*, I. Kadiri^b, K. Sbai^a , M. Rahmoune^a

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-6, 2016, DOI:10.5098/hmt.7.35

Abstract Boiling heat transfer process is important because it is a way to increase the flux density transmitted at low temperature differences. To quantify the thermal exchanges, we performed an experimental study of the nitrogen pool boiling, in transient conditions, on a horizontal brass ribbon for a fixed flux density. The results show that there is no break between the monophasic convection zone and the nucleated boiling region. In the nucleated boiling zone, the temperature variations are very small. We also note that the overheating required to trigger boiling increases with the time delay after the activation of nucleation sites. More >

Huifeng Yang, Mingwang Wu, Rixin Gu, Hang Cao, Kai Xiao, Benkai Shi^*

Journal of Renewable Materials, Vol.11, No.12, pp. 4175-4195, 2023, DOI:10.32604/jrm.2023.028507

Abstract This article presents experimental results of steel-timber-steel (STS) joints loaded parallel to grain. Eight groups of specimens were designed, and tensile tests were performed. The fastener types and fastener numbers were considered to evaluate the tensile strengths and ductility performances of the STS joints. The screws with 6 mm diameter and the innovative steel-tubes with 18 mm diameter were adopted as connecting fasteners. The experimental results were discussed in terms of yielding and ultimate strengths, slip stiffness, and ductility factors. The ductility classification and failure mechanisms of each group of specimens were analyzed. It was demonstrated that the STS joint… More >

Zhengyong Wang¹, Jianhua Zhang², Guoliang Su³, Peixing Yang⁴, Xiantao Fan⁴, Shuzhan Bai¹, Ke Sun^1,*, Guihua Wang^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.1, pp. 193-204, 2024, DOI:10.32604/fdmp.2023.030561

Abstract A Diesel Particulate Filter (DPF) is a critical device for diesel engine exhaust products treatment. When using active-regeneration purification methods, on the one hand, a spatially irregular gas flow can produce relatively high local temperatures, potentially resulting in damage to the carrier; On the other hand, the internal temperature field can also undergo significant changes contributing to increase this risk. This study explores the gas flow uniformity in a DPF carrier and the related temperature behavior under drop-to-idle (DTI) condition by means of bench tests. It is shown that the considered silicon carbide carrier exhibits good flow uniformity, with a… More >

Shiyang Song^1,*, Tongxin Han²

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.1, pp. 127-145, 2024, DOI:10.32604/fdmp.2023.030137

Abstract Aiming to mitigate the aerodynamic lift force imbalance between pantograph strips, which exacerbates wear and affects the current collection performance of the pantograph-catenary system, a study has been conducted to support the beam deflector optimization using a combination of experimental measurements and computational fluid dynamics (CFD) simulations. The results demonstrate that the size, position, and installation orientation of the wind deflectors significantly influence the amount of force compensation. They also indicate that the front strip deflectors should be installed downwards and the rear strip deflectors upwards, thereby forming a “π” shape. Moreover, the lift force compensation provided by the wind… More >

Guiwu Lin, Kaige Liu, Yuliang Chen^*, Yunpeng Ji, Rui Jiang

Journal of Renewable Materials, Vol.11, No.11, pp. 3957-3975, 2023, DOI:10.32604/jrm.2023.028290

Abstract This paper presents an experimental study to explore the compressive properties of fiber recycled aggregate concrete. A total of 75 specimens with the replacement rate of recycled coarse aggregate and fiber type were conducted under a uniaxial compressive test. The failure modes, stress-strain whole curves, peak stress, peak strain, and energy dissipation capacity were systematically observed and revealed. Test results indicate that steel fiber has the best modification effect on energy dissipation capacity and the toughness index of recycled concrete, corresponding to the enhancement of 81.75% and 22.90% on average. The addition of polyvinyl alcohol fiber can effectively improve the… More > Graphic Abstract

Decheng Li¹, Yan Zhang², Dongdong Ma², Haozhe Geng¹, Yu Wu^1,2,*

Energy Engineering, Vol.120, No.11, pp. 2503-2516, 2023, DOI:10.32604/ee.2023.041803

Abstract The fracturing process of sandstone is inherently complex due to its loose internal structure and deformation adaptability. Liquid nitrogen pre-injection has emerged as a promising approach to damage reservoir rocks, effectively reducing fracture pressure and establishing intricate fracture networks, thus offering a potential solution for reservoir reconstruction. To unravel the fundamental mechanisms governing sandstone fracturing behaviors following liquid nitrogen pre-injection, sandstone fracturing experiments were conducted under varying durations of liquid nitrogen injection, rock temperature, and in-situ stress conditions. The experiments showcased the evolution of injection pressure and fracture characteristics under different testing conditions, complemented by electron microscope analysis to elucidate… More >

Yun Lei^1,2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.12, pp. 3021-3032, 2023, DOI:10.32604/fdmp.2023.029570

Abstract The highly inefficient simultaneous extraction of coal and gas from low-permeability and high-gas coal seams in deep mines is a major problem often restricting the sustainable development of coal industry. A possible way to solve this problem under deep and complex geological conditions is represented by the technology based on the phase-change induced explosion of liquid carbon dioxide. In this work, the mechanism of formation of the coal mass fracture circle resulting from the gas cracking process is theoretically analyzed. Numerical simulations show that a blasting crushing zone with a radius of 1.0 m is formed around the blasting hole.… More >

Weizhi Liao¹, Xiaoyun Xia^1,3, Xiaojun Jia¹, Shigen Shen^2,*, Helin Zhuang^4,*, Xianchao Zhang¹

CMC-Computers, Materials & Continua, Vol.76, No.3, pp. 3297-3323, 2023, DOI:10.32604/cmc.2023.040967

Abstract As a new bionic algorithm, Spider Monkey Optimization (SMO) has been widely used in various complex optimization problems in recent years. However, the new space exploration power of SMO is limited and the diversity of the population in SMO is not abundant. Thus, this paper focuses on how to reconstruct SMO to improve its performance, and a novel spider monkey optimization algorithm with opposition-based learning and orthogonal experimental design (SMO³) is developed. A position updating method based on the historical optimal domain and particle swarm for Local Leader Phase (LLP) and Global Leader Phase (GLP) is presented to improve the… More >

Xiaoyu Zhang^1,2, Huizhong Zeng², Shaohui Zhang², Yan Zhang^3,*, Mi Xiao⁴, Liping Liu², Hao Zhou^2,*, Hongyou Chai², Liang Gao⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.1, pp. 201-220, 2024, DOI:10.32604/cmes.2023.029389

Abstract Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting from the sandwich effect. Such structures can be fabricated by metallic additive manufacturing technique, such as selective laser melting (SLM). However, the maximum dimensions of actual structures are usually in a sub-meter scale, which results in restrictions on their appliance in aerospace and other fields. In this work, a meter-scale thin-walled structure with lattice infill is designed for the fuel tank supporting component of the satellite by integrating a self-supporting lattice into the thickness optimization of the thin-wall. The… More >