Journal of King Saud University, Engineering Sciences最新文献_第9页

The effects of adding nano clay and nano zinc oxide on asphalt cement rheology 纳米粘土和纳米氧化锌的加入对沥青水泥流变的影响

Journal of King Saud University, Engineering Sciences Pub Date : 2023-05-01 DOI: 10.1016/j.jksues.2021.03.010

Bara' Al-Mistarehi , Aslam Al-Omari , Madhar Taamneh , Rana Imam , Deya' Al-Deen Khafaja

{"title":"The effects of adding nano clay and nano zinc oxide on asphalt cement rheology","authors":"Bara' Al-Mistarehi , Aslam Al-Omari , Madhar Taamneh , Rana Imam , Deya' Al-Deen Khafaja","doi":"10.1016/j.jksues.2021.03.010","DOIUrl":"10.1016/j.jksues.2021.03.010","url":null,"abstract":"<div><p>This study aims at investigating the effects on asphalt cement (AC) rheology when adding Nano Clay (NC) and Nano Zinc Oxide (NZnO) compounds. The tested contents of NC were 8%, 10%, and 12%, while those of NZnO were 1%, 2%, and 3% by weight of the AC. The study used AC of 60/70 penetration grade since it is the most commonly used in the Middle East region. Different tests were performed on both the control AC (CAC) and modified AC (MAC), including dynamic shear rheometer (DSR), Softening point (SP), penetration, flash and fire points (FFP), bending beam rheometer (BBR), and viscosity tests. These tests' results demonstrated that the modifiers tend to decrease the penetration values but increase the FFP, viscosity, and SP values. A slight improvement in the rheological properties of AC at high temperatures was also evident from the addition of NC or NZnO. Furthermore, adding either modifier led to significant improvements at low-temperature conditions in the AC's performance and cracking resistance. The optimum modifiers of NC and NZnO were 10% and 3% by weight of the AC, respectively.</p></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jksues.2021.03.010","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45641253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Hydrodynamics of the swirling steam-water two-phase flows over a surface with protrusions: Shape optimization and effect of rise in temperature on drag reduction 有凸起表面上旋转蒸汽-水两相流的流体动力学：形状优化和温度升高对减阻的影响

Journal of King Saud University, Engineering Sciences Pub Date : 2023-05-01 DOI: 10.1016/j.jksues.2021.03.013

Afrasyab Khan , Khairuddin Sanaullah , Andrew Ragai Henry Rigit , Atta Ullah

{"title":"Hydrodynamics of the swirling steam-water two-phase flows over a surface with protrusions: Shape optimization and effect of rise in temperature on drag reduction","authors":"Afrasyab Khan , Khairuddin Sanaullah , Andrew Ragai Henry Rigit , Atta Ullah","doi":"10.1016/j.jksues.2021.03.013","DOIUrl":"10.1016/j.jksues.2021.03.013","url":null,"abstract":"<div><p>The current study studies the drag reduction offered by the plate with protrusions to the swirling steam-water two-phase flows. Protrusions of different types, having triangular, sinusoidal, and trapezoidal shapes, are investigated. The variations and modifications were made in the dimensions and orientations (facing along or across, flush-mounted or protruded into the swirling flows), to test the effectivity of these protrusions. At 5 bars of inlet gauge pressure and rpm varying from 360 to 1440, the trapezoidal shape provides the most effective drag reduction. It is also found from the PIV images of the fluid region near the protrusions that the drag reduction in the trapezoidal-shaped protrusions occurs mainly due to the secondary flow structures formation over those protrusions.</p><p>On the one hand, the lateral spacing between the adjacent protrusions created the region of strengthening and expansion against the higher opposite inertial forces from the main swirling core fluids. While on the other hand, these spacings justify the impact of the axial elongation of the vortices above the protrusion tips. Further trends in drag reduction have also been investigated by observing the effect of the rise in the temperature of the fluid medium. Reduction in drag from 1.3 to 1.6% is noted using the trapezoidal protrusions for a temperature rise of 25–60 °C. It is also observed that the drag reduction profiles show a rising trend under the influence of the rising Nusselt Number. This trend is attributed to the decrease in viscosity. Whereas under the influence of a rising Prandtl number, the drag reduction shows a decreasing trend, mainly attributed to the rise in the pressure drop at the boundary layers and the pressure drop due to the friction.</p></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jksues.2021.03.013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46255852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Improving the activity and stability of turtle shell-derived catalyst in alcoholysis of degraded vegetable oil: An experimental design approach 提高甲壳衍生催化剂在降解植物油醇解中的活性和稳定性:实验设计方法

Journal of King Saud University, Engineering Sciences Pub Date : 2023-05-01 DOI: 10.1016/j.jksues.2021.05.001

Henry Oghenero Orugba, Lawrence Chukwuka Edomwonyi-Otu

引用次数: 5

Experimental investigation of rubberized reinforced concrete continuous deep beams 橡胶钢筋混凝土连续深梁试验研究

Journal of King Saud University, Engineering Sciences Pub Date : 2023-03-01 DOI: 10.1016/j.jksues.2021.03.001

Ali Abdulameer Kadhim, Hayder Mohammed Kadhim

{"title":"Experimental investigation of rubberized reinforced concrete continuous deep beams","authors":"Ali Abdulameer Kadhim, Hayder Mohammed Kadhim","doi":"10.1016/j.jksues.2021.03.001","DOIUrl":"10.1016/j.jksues.2021.03.001","url":null,"abstract":"<div><p>Results of fourteen two-span continuous deep beams made from ordinary reinforced concrete (ORC) as a reference and rubberized reinforced concrete (RRC) is presented and discussed in this research. The main parameters are the rubber ratios as a replacement with coarse and fine aggregate and the shear span/depth ratio (a/h) is 1.33 and 1.66. Chip and crumb rubbers were used to replace coarse and fine aggregate respectively in four different amounts by volume (5%, 10%, 15%, and 20%). The proposed mix shows an ability to replace 20% of the aggregate (coarse or fine), and the production is still structural concrete. All beams design to fail in shear. The main crack is formatted between the intermediate support and the applied load diagonally. In spite of the inclusion of waste tire rubber in concrete having specific apparent degradations, the potential benefit seems to overlook the adverse effects and also provides the primary significant value of resolution for rubber waste problems. The results show that 20% volumetric substitution of natural coarse or fine aggregates with tier rubber reduced the ultimate load of continuous deep beams by 32.06% and 32.65% but significantly increases the ultimate deflection by 83.07% and 106.28% respectively. The ductility of rubberized continuous deep beams increased up to 36.95% when the replacement ratio of crumb rubber is 20%.</p></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jksues.2021.03.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46418244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Chip experimental analysis approach obtained by micro-end-milling in (Ti-6Al-4 V) titanium alloy and (7075) aluminium alloy 通过微端铣削获得(ti - 6al - 4v)钛合金和(7075)铝合金的切屑实验分析方法

Journal of King Saud University, Engineering Sciences Pub Date : 2023-03-01 DOI: 10.1016/j.jksues.2021.04.003

Mario J. Remolina , Marco A. Velasco , Ernesto Córdoba

引用次数: 2

Log-periodic enactment of a novel patch with square DGS for Ku-band applications Ku波段应用的方形DGS新补丁的对数周期制定

Journal of King Saud University, Engineering Sciences Pub Date : 2023-03-01 DOI: 10.1016/j.jksues.2021.03.015

Ribhu Abhusan Panda, Debasis Mishra

引用次数: 0

Repeatability of concrete rebound hardness using comprehensive statistical analysis 综合统计分析混凝土回弹硬度的重复性

Journal of King Saud University, Engineering Sciences Pub Date : 2023-03-01 DOI: 10.1016/j.jksues.2021.02.013

Hemraj R. Kumavat, Narayan R. Chandak

{"title":"Repeatability of concrete rebound hardness using comprehensive statistical analysis","authors":"Hemraj R. Kumavat, Narayan R. Chandak","doi":"10.1016/j.jksues.2021.02.013","DOIUrl":"10.1016/j.jksues.2021.02.013","url":null,"abstract":"<div><p>The reliability of the result significantly affects the use of the Coefficient of Variation (within the test variation), which reflects the variability of the concrete properties rather than the standard deviation. For the estimation of reliability and precision, comprehensive statistical analysis (within test variation) is conducted on 534 test samples using a rebound hammer. Different standards, like BIS, EN, ACI, and ASTM, are used in this study to compare the test results. Empirical research revealed that there are contradictions in literature as well as the standards used in many countries. The present paper focuses on detailed investigations of uncertainty measurements of the surface hardness test by statistical parameters (range of rebound index, standard deviation, and Coefficient of Variation). The unbiased estimate of the variability parameters from the published results has been verified concerning to the European standard. Concrete parameters namely cement type, water to cement ratio, compaction deficiency, curing condition, and elevated temperature have an impact on the output of the rebound hardness in terms of the variability of the compressive strength. Based on the results, the authors are willing to propose amendments to the Indian code graciously in compliance with the variability of the rebound hammer.</p></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jksues.2021.02.013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45790809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

A dependence study: Molecular weight of polyethylene glycol (PEG) ON La0.7Sr0.3Co0.2Fe0.8O3−δ (LSCF 7328) hollow fiber membrane for oxygen permeation 聚乙二醇(PEG)对La0.7Sr0.3Co0.2Fe0.8O3−δ (LSCF 7328)中空纤维膜透氧性能的依赖研究

Journal of King Saud University, Engineering Sciences Pub Date : 2023-03-01 DOI: 10.1016/j.jksues.2021.05.003

Hamzah Fansuri , Alfia Dewi Masyitoh , Silvana Dwi Nurherdiana , Wahyu Prasetyo Utomo , Triyanda Gunawan , Nurul Widiastuti , Mohd Hafiz Dzarfan Othman , Ahmad Fauzi Ismail , Subaer

{"title":"A dependence study: Molecular weight of polyethylene glycol (PEG) ON La0.7Sr0.3Co0.2Fe0.8O3−δ (LSCF 7328) hollow fiber membrane for oxygen permeation","authors":"Hamzah Fansuri , Alfia Dewi Masyitoh , Silvana Dwi Nurherdiana , Wahyu Prasetyo Utomo , Triyanda Gunawan , Nurul Widiastuti , Mohd Hafiz Dzarfan Othman , Ahmad Fauzi Ismail , Subaer","doi":"10.1016/j.jksues.2021.05.003","DOIUrl":"10.1016/j.jksues.2021.05.003","url":null,"abstract":"<div><p>In an effort to further improvement of LSCF hollow fiber membrane properties in oxygen purification applications, this work studied the use of polyethylene glycol (PEG) with a different molecular weights of 2000, 3400 and 6000 Da as a pore former. A well-prepared hollow fiber membrane was successfully fabricated via extrusion followed by a sintering method. The results showed that the addition of PEG increased the viscosity of the dope suspension and formed a constant asymmetric pore configuration of the membrane after sintering at 1250 °C. The increasing molecular weight of PEG also leads to a decrease in the mechanical strength of the membranes, indicating that finger-like pores were sacrificed by forming irregular pores. The gas tightness was also examined under room temperature which showed that membrane with PEG 3400 achieved the best tightness with the nitrogen permeability of 3.55 × 10<sup>−5</sup> mol·m<sup>−2</sup>·s<sup>−1</sup>·Pa<sup>−1</sup>. The oxygen permeation of the membranes was also influenced by the addition of PEG, where the highest oxygen permeation flux of 6.07 × 10<sup>−8</sup> mol·cm<sup>−2</sup>·s<sup>−1</sup> was obtained using a hollow fiber membrane with PEG 3400 due to the existence of the lowest dense layer thickness.</p></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jksues.2021.05.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46854591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Technical assessment of biodiesel storage tank; A corrosion case study 生物柴油储罐技术评价;腐蚀案例研究

Journal of King Saud University, Engineering Sciences Pub Date : 2023-03-01 DOI: 10.1016/j.jksues.2021.03.016

Leily Nurul Komariah , Susila Arita , Baikuni E. Prianda , Tri K. Dewi

{"title":"Technical assessment of biodiesel storage tank; A corrosion case study","authors":"Leily Nurul Komariah , Susila Arita , Baikuni E. Prianda , Tri K. Dewi","doi":"10.1016/j.jksues.2021.03.016","DOIUrl":"10.1016/j.jksues.2021.03.016","url":null,"abstract":"<div><p>The compatibility problems become the main concern in the utilization of biodiesel especially regarding degradation and corrosion. The present study is conducted to describe the corrosion behaviour that occurs in steel tanks after contact with palm-based biodiesel for a period of 7 months. The storage tank used is respectively made of galvanised steel (GS), carbon steel (CS) and stainless steel (SS). It is performed in vertical cylinders with a floating-roof model. In every 30 days of storage time, the profile changes in the wall, roof and base surface of each tank were observed. The oil fuel properties were monitored in the parameter of viscosity, acid numbers, water content and oil colour. The topographic profiles on the surface of the walls and bottom of each tank wetted by biodiesel were examined over three zones inside the tanks using an endoscope imager. The main results of this study indicate that tank steel with different protective layers exhibits different types of corrosion. The corrosion was localized in SS tanks but generalized in GS and CS tanks. The oil contamination in SS tanks was relatively lower than that in CS and GS tanks. The type of corrosion performed differently in different zones on the inside of the tank. The potential for leaks is greater at the base than on the walls and roof of the storage tank.</p></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jksues.2021.03.016","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49195666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

On proposing a non-intrusive device and methodology to monitor motor degradation 提出一种非侵入式监测电机退化的装置和方法

Journal of King Saud University, Engineering Sciences Pub Date : 2023-03-01 DOI: 10.1016/j.jksues.2021.04.007

Henrique Cafruni Kuhn , Rodrigo da Rosa Righi , Cesar David Paredes Crovato

{"title":"On proposing a non-intrusive device and methodology to monitor motor degradation","authors":"Henrique Cafruni Kuhn , Rodrigo da Rosa Righi , Cesar David Paredes Crovato","doi":"10.1016/j.jksues.2021.04.007","DOIUrl":"10.1016/j.jksues.2021.04.007","url":null,"abstract":"<div><p>Monitoring the degradation of induction motors is an essential concern for industries, especially when there are high costs related to maintenance and their stops. Nowadays, there are many non-invasive ways to monitor the health status of induction motors, including sensors to measure temperature, magnetic field, vibration, current, and power. However, installing these sensors may not be a simple task since intrusive procedures such as engine disassembling, wire separation, and engine interruption are commonly observed. Thus, we propose MUCLA (Multiphase Clamp and Tracking - patent pending) as a new device and methodology for monitoring motor degradation by analyzing its stator current. MUCLA introduces a non-invasive current sensors array on a proposed clamp in the hardware perspective, while a spectral tracking methodology refers to our novelty in the software viewpoint. For end-users, the main MUCLA contribution relies on the combination of the simplicity of installation and the possibility of using the proposed device even when considering Variable-Frequency Drive powered engines. The results obtained with both simulation and practical tests show encouraging results over different input workloads and emulated degradation. Compared to the current initiatives, we can classify MUCLA as a better solution for industrial plants in terms of installation time, installation complexity, and cost.</p></div>","PeriodicalId":35558,"journal":{"name":"Journal of King Saud University, Engineering Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jksues.2021.04.007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42758172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0