Open Engineering最新文献

Effect of adverse slope on performance of USBR II stilling basin 逆坡对USBR II型消力池性能的影响

Open Engineering Pub Date : 2023-01-01 DOI: 10.1515/eng-2022-0469

Layla Ali Mohammed Saleh, Saleh Issa Khassaf

{"title":"Effect of adverse slope on performance of USBR II stilling basin","authors":"Layla Ali Mohammed Saleh, Saleh Issa Khassaf","doi":"10.1515/eng-2022-0469","DOIUrl":"https://doi.org/10.1515/eng-2022-0469","url":null,"abstract":"Abstract This article focuses on the United States Bureau of Reclamation (USBR) Type II stilling basin, which has chute blocks, an end dentated sill, and a flat floor. USBR provides general design criteria to contain the hydraulic jump within the stilling basin. The sequent depth ratio, energy dissipation ratio, and stilling basin dimensions of the hydraulic jump are changed when the bed slope of USBR II stilling basins is changed. This study aimed to investigate the effects of adverse slope on the performance of USBR II stilling basin in terms of sequent depth ratio and energy dissipation. Six discharges ranging from 8 to 33 lps were applied to the USBR II stilling basin with bed slopes ( S ) of −0.085, −0.055, −0.035, and 0. Results demonstrated that for Q = 13 and 8 lps, the basin performs better than other models with S = −0.085, increasing energy dissipation by about 10% compared to a typical basin due to the formation of a free hydraulic jump downstream dentated end sill. On the other hand, the floor downstream of the dentated end sill needs more protection against this free jump, and this case becomes economically expensive. In other cases, the downstream jump was submerged, resulting in a counterintuitive current and reverse roller based on the submerged ratio, reducing the effectiveness of the stilling basin. In addition, the modified design of the stilling basin resulted in a shorter effective length that included the hydraulic jump downstream spillway, thereby reducing internal friction. As a result, the standard USBR II with a flatbed is less expensive and more efficient than the adverse slope basin.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136258932","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

Risk management based on the best value approach and its application in conditions of the Czech Republic 基于最佳价值方法的风险管理及其在捷克共和国的应用

IF 1.7

Open Engineering Pub Date : 2023-01-01 DOI: 10.1515/eng-2022-0438

P. Marvan, V. Hromádka, E. Vítková

引用次数: 0

Human factors in aviation: Fatigue management in ramp workers 航空中的人为因素：停机坪工作人员的疲劳管理

IF 1.7

Open Engineering Pub Date : 2023-01-01 DOI: 10.1515/eng-2022-0411

Carlota Morais, J. Ribeiro, Jorge Silva

引用次数: 0

Improvement of CBR of gypsum subgrade soil by cement kiln dust and granulated blast-furnace slag 水泥窑粉尘和矿渣颗粒改善石膏路基土的CBR

IF 1.7

Open Engineering Pub Date : 2023-01-01 DOI: 10.1515/eng-2022-0397

Asaad Mohammed Baqir Al-Gharrawi, Tawfek Sheer Ali, A. K. Alzerjawi, M. K. Fakhraldin, H. A. Abdul-Husain

引用次数: 0

Dislocated time sequences – deep neural network for broken bearing diagnosis 错位时间序列的深度神经网络故障诊断

IF 1.7

Open Engineering Pub Date : 2023-01-01 DOI: 10.1515/eng-2022-0402

Pramudyana Agus Harlianto, T. B. Adji, N. A. Setiawan

引用次数: 0

Design parameters and mechanical efficiency of jet wind turbine under high wind speed conditions 高风速条件下射流风力机的设计参数与机械效率

Open Engineering Pub Date : 2023-01-01 DOI: 10.1515/eng-2022-0450

Abbas Waheed Dahham, Asylbek Zhumabekovich Kasenov, Mohammed Wahhab Aljibory, Mahmood Mohammed Hilal, Kairatolla Kayrollinovich Abishev, Mussina Zhanara Kereyovna, Nurbolat Sakenovich Sembayev, Hussein Waheed Dahham, Petr Olegovich Bykov, Adamov Abilmazhin Alirakhimovich

{"title":"Design parameters and mechanical efficiency of jet wind turbine under high wind speed conditions","authors":"Abbas Waheed Dahham, Asylbek Zhumabekovich Kasenov, Mohammed Wahhab Aljibory, Mahmood Mohammed Hilal, Kairatolla Kayrollinovich Abishev, Mussina Zhanara Kereyovna, Nurbolat Sakenovich Sembayev, Hussein Waheed Dahham, Petr Olegovich Bykov, Adamov Abilmazhin Alirakhimovich","doi":"10.1515/eng-2022-0450","DOIUrl":"https://doi.org/10.1515/eng-2022-0450","url":null,"abstract":"Abstract Turbines are one of the most important means of producing clean energy, as they do not cause any negative emissions affecting the environment. Recently, the need to design turbines capable of facing strong winds has appeared because the currently designed turbines must be cut off in such circumstances. This study aims to find the best design parameters and investigate the efficiency of the jet turbine at high wind speed conditions. SolidWorks and MatLab are used to design and analyze small jet wind turbines. The design parameters were chosen to obtain the best efficiency. The turbine diameter is 0.5 m, and the short blade length helps withstand the generated stresses due to strong wind, especially fatigue stress, and resists bending. Blade pitch angle beta starts from 2° from the vertical axis at the hub and changes harmonically along the length to end at an angle of 88° at the blade’s tip to allow air to pass through and not form a wall. The blade number has chosen 15 blades, corresponding to the Betz limit, to obtain the maximum power coefficient. As a result, the assigned power was obtained at a wind speed of 28 m/s. At a lower wind speed, it will work with acceptable efficiency and more efficiently at higher speeds. Therefore, this turbine is suitable to use in such cases.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135401917","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

Effect of varied waste concrete ratios on the mechanical properties of polymer concrete 不同废混凝土配比对聚合物混凝土力学性能的影响

Open Engineering Pub Date : 2023-01-01 DOI: 10.1515/eng-2022-0468

Aliaa Rasheed, Shatha Sadiq, Aseel Shaaban

{"title":"Effect of varied waste concrete ratios on the mechanical properties of polymer concrete","authors":"Aliaa Rasheed, Shatha Sadiq, Aseel Shaaban","doi":"10.1515/eng-2022-0468","DOIUrl":"https://doi.org/10.1515/eng-2022-0468","url":null,"abstract":"Abstract Polymer concrete (PC) was developed at the end of the 1950s and gained popularity in the 1970s for precast parts, flimsy floor coverings, and repairs. Due to its superior performance over traditional Portland cement concrete, which offers many benefits, including mechanical properties, quick hardening, and durability. In this article, polymeric concrete was made using a mixture of sand and epoxy, and different proportions of sand were replaced with crushed concrete waste. This study found that the ideal ratio between resin and fine aggregate was 23% resin to 77% fine aggregate in terms of the total weight of the combination to get the best dispersion of fine aggregate. Waste concrete replaced 5, 10, 15, and 20% of aggregate in PC, respectively. It was further demonstrated that increased waste concrete aggregate content in PC increased the 28-day compressive strength by 7.7, 13.44, 16.8, and 18.97%, respectively; flexural strength increased by 16.68, 25.32, 37.16, and 47.71% at 28 days’ age; and direct tensile strength was higher than the reference mixture by values of 3.41, 17.21, 23.54, and 30.38% at 28 days age. The findings recommended using recycled fine aggregate on PC and suggested a 20% replacement ratio as an optimum percentage.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":"99 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136207652","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

A comparative study to solve fractional initial value problems in discrete domain 离散域分数阶初值问题的比较研究

Open Engineering Pub Date : 2023-01-01 DOI: 10.1515/eng-2022-0480

Alaa Mohsin Abed, Hosein Jafari, Mohammed Sahib Mechee

引用次数: 0

Research on dynamical properties of a three-wheeled electric vehicle from the point of view of driving safety 从驾驶安全角度研究三轮电动汽车的动力特性

IF 1.7

Open Engineering Pub Date : 2023-01-01 DOI: 10.1515/eng-2022-0441

M. Blatnický, J. Dižo, Andrej Suchánek, P. Šťastniak

{"title":"Research on dynamical properties of a three-wheeled electric vehicle from the point of view of driving safety","authors":"M. Blatnický, J. Dižo, Andrej Suchánek, P. Šťastniak","doi":"10.1515/eng-2022-0441","DOIUrl":"https://doi.org/10.1515/eng-2022-0441","url":null,"abstract":"Abstract Many vehicles in urban and suburban environment are occupied just by one passenger, i.e. by a driver. Therefore, it is worth to think about vehicles, which would be smaller and lighter and which would include environmental-friendly power source. One such vehicle is the presented three-wheeled electric vehicle. This vehicle is designed for one passenger and it is powered by an ecologic electric powertrain. Therefore, it is necessary to research its driving properties. There are two types of vehicle designs, an original design and a modified design with a reworked body. Both are characterised by the symmetrical distribution of the mass to the longitudinal axis. In terms of driving properties of the vehicle, overturning stability during cornering and vertical dynamics in terms of safety are assessed for both original and modified designs. The article presents the main description of the original and modified designs of the three-wheeled vehicle and results from simulation computations focused on analysis of the over-turning stability. It has been revealed that the original vehicle, which is lighter, has better dynamical properties in curves with regards to driving and the higher total weight of the modified vehicle is safer in terms of vertical dynamics.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49542938","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

Seismic evaluation cylindrical concrete shells 圆柱形混凝土壳体的抗震评估

IF 1.7

Open Engineering Pub Date : 2023-01-01 DOI: 10.1515/eng-2022-0417

A. M. Hammood, David A. M. Jawad

{"title":"Seismic evaluation cylindrical concrete shells","authors":"A. M. Hammood, David A. M. Jawad","doi":"10.1515/eng-2022-0417","DOIUrl":"https://doi.org/10.1515/eng-2022-0417","url":null,"abstract":"Abstract The reasons for concrete roof shells’ apparent seismic resistance have been subject to limited research but they have been shown to be inherently resilient to earthquakes. Shells constructed of concrete exhibit high structural efficiency and can therefore be made very thin. As a result of their relatively lightweight nature, thin shell structures are implicitly resistant to earthquake forces. The shell structure is typically designed so that it performs optimally under gravity loads, which are carried mainly by membrane action over the shell surface. As earthquakes induce unexpected horizontal forces, concrete shell structures can be damaged by bending stresses. By studying 8 cm-thick concrete roof shells using parametric analysis, this research shows that small and midsized (span <30 m) thin concrete roof shells can indeed be intrinsically earthquake resistant. These structures have high geometric stiffness and low mass, which results in fundamental frequencies far higher than those of realistic seismic events. Under earthquake excitation, these characteristics result in elastic shell behavior, without exceeding the maximum concrete strength. A shallow shell exhibits greater stress in response to earthquake vibrations caused by the vertical components than by horizontal components. Further, by increasing the rise and curvature of large shells, the fundamental frequency increases and the damaging effect of vertical earthquake vibration is reduced. The aim of this study in general is to show the analysis and the effect of earthquakes on cylindrical concrete shells.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49614557","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