Strojniski Vestnik-Journal of Mechanical Engineering最新文献_第5页

The Influence of Machining Parameters on the Surface Porosity of a Closed-Cell Aluminium Foam 加工参数对闭孔泡沫铝表面孔隙率的影响

IF 1.7 4区工程技术

Strojniski Vestnik-Journal of Mechanical Engineering Pub Date : 2019-12-20 DOI: 10.5545/sv-jme.2019.6297

B. Razboršek, Janez Gotlih, Timi Karner, M. Ficko

引用次数: 6

Heat Dissipation from Stationary Passenger Car Brake Discs 静止客车制动盘的散热

IF 1.7 4区工程技术

Strojniski Vestnik-Journal of Mechanical Engineering Pub Date : 2019-12-20 DOI: 10.5545/sv-jme.2019.6002

Stergios Topouris, Dragan Stamenković, Michel Olphe-Galliard, V. Popovic, M. Tirovic

{"title":"Heat Dissipation from Stationary Passenger Car Brake Discs","authors":"Stergios Topouris, Dragan Stamenković, Michel Olphe-Galliard, V. Popovic, M. Tirovic","doi":"10.5545/sv-jme.2019.6002","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6002","url":null,"abstract":"The paper presents experimental investigation of the heat dissipation from stationary brake discs concentrated on four disc designs, a ventilated disc with radial vanes, two types of ventilated discs with curved vanes - a non-drilled and cross-drilled disc, and a solid disc. The experiments were conducted on a purpose built Thermal Spin Rig and provided repeatable and accurate temperature measurement and reliable prediction of the total, convective and radiative heat dissipation coefficients. The values obtained compare favourably with Computational Fluid Dynamics results for the ventilated disc with radial vanes and solid disc, though the differences were somewhat pronounced for the ventilated disc. The speeds of the hot air rising above the disc are under 1 m/s, hence too low to experimentally validate. However, the use of a smoke generator and suitable probe was very useful in qualitatively validating the flow patterns for all four disc designs. Convective heat transfer coefficients increase with temperature but the values are very low, typically between 3 and 5 W/m2K for the disc designs and temperature range analysed. As expected, from the four designs studied, the disc with radial vanes has highest convective heat dissipation coefficient and the solid disc the lowest, being about 30% inferior. Convective heat dissipation coefficient for the discs with curved vanes was about 20% lower than for the disc with radial vanes, with the cross drilled design showing marginal improvement at higher temperatures.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"17 1","pages":"15-28"},"PeriodicalIF":1.7,"publicationDate":"2019-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87225805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Design and Performance Analysis of Airbag-Soft-Manipulator According to Characteristic Parameters 基于特征参数的气囊式软机械臂设计与性能分析

IF 1.7 4区工程技术

Strojniski Vestnik-Journal of Mechanical Engineering Pub Date : 2019-12-20 DOI: 10.5545/sv-jme.2019.6228

Liu Peng, Yonghong Liu, Ke Wang, Xiaoxuan Wei, Chao Xin, Xinlei Wu

引用次数: 1

Stress Analysis of a Pipeline as a Hydropower Plant Structural Element 水电站管道结构单元的应力分析

IF 1.7 4区工程技术

Strojniski Vestnik-Journal of Mechanical Engineering Pub Date : 2019-12-20 DOI: 10.5545/sv-jme.2019.6157

Stefan Ćulafić, T. Maneski, D. Bajić

{"title":"Stress Analysis of a Pipeline as a Hydropower Plant Structural Element","authors":"Stefan Ćulafić, T. Maneski, D. Bajić","doi":"10.5545/sv-jme.2019.6157","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6157","url":null,"abstract":"This paper describes pipeline stress analysis, primarilybranch junctions, as a structural element in hydro-power plants. Pipelines are exposed to internal pressure,which is present under working conditions. Analysis of stresses in the pipeline of the hydropower plant is based on analytical, numerical, and experimental methods. In this paper, we will define the critical elements of the pipeline. After that, we will determine critical areas in the branch junction, under experimental conditions, where strain gauges should be installed. The obtained resultsshow that a boiler formula can be efficiently applied in the stress analysis. Also, a correlation between the internal pressure and the maximum circumferential stresses in the elastic zone is given. In the final sections of the paper, the limit value of the internal pressure as a load for which stress in the zone of plasticity appears and the safety factor of the branch junction in the exploitation conditions are determined. The contribution of this work is the unification and deepening of the topic related to the problem of the testing ofhydro-power structural elements.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"53 1","pages":"51-60"},"PeriodicalIF":1.7,"publicationDate":"2019-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76064862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Cavitation as a Potential Technology for Wastewater Management – An Example of Enhanced Nutrient Release from Secondary Pulp and Paper Mill Sludge 空化作为废水管理的一种潜在技术——以二次纸浆和造纸厂污泥中养分释放增强为例

IF 1.7 4区工程技术

Strojniski Vestnik-Journal of Mechanical Engineering Pub Date : 2019-11-18 DOI: 10.5545/sv-jme.2019.6328

M. Sežun, J. Kosel, M. Zupanc, M. Hočevar, J. Vrtovšek, M. Petkovšek, M. Dular

{"title":"Cavitation as a Potential Technology for Wastewater Management – An Example of Enhanced Nutrient Release from Secondary Pulp and Paper Mill Sludge","authors":"M. Sežun, J. Kosel, M. Zupanc, M. Hočevar, J. Vrtovšek, M. Petkovšek, M. Dular","doi":"10.5545/sv-jme.2019.6328","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6328","url":null,"abstract":"Wastewater recycling and sludge removal in the paper industry account for about 60 % of all process costs. New and environmentally friendly wastewater treatment techniques are, therefore, continually being developed. Cavitation exploitation is currently a well-investigated topic that is also interesting for the paper production industry. This study investigates efficiency of hydrodynamic cavitation alone and in combination with the addition of NaOH for the treatment of secondary pulp and paper mill sludge in order to enhance nutrient release. First, two laboratory-scale devices were tested: the blow-through and the rotating hydrodynamic cavitation generator. The latter set-up proved to be more efficient: therefore, further experiments were performed on its pilot-scale version. The results showed an increase of soluble chemical oxygen demand (CODs) by 514 mg/L, total nitrogen (Nt) by 17.4 mg/L, and total phosphorous (Pt) by 2.3 mg/L. To further increase nutrient release combination of cavitation and sludge sample alkalinization was tested. The addition of NaOH and 30 min cavitation of secondary sludge (500 L) significantly improved CODs and Nt release by 2400 mg/L and 120 mg/L, respectively. Microbiological photos revealed a definite disintegration of sludge flocks. According to our estimates, 1.9 kg of released CODs from alkaline pre-treated and cavitated sludge would cost only one euro.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"44 7","pages":"641-649"},"PeriodicalIF":1.7,"publicationDate":"2019-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72581205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 19

Multi-Physics and Multi-Scale Meshless Simulation System for Direct-Chill Casting of Aluminium Alloys 铝合金直冷铸造多物理场多尺度无网格仿真系统

IF 1.7 4区工程技术

Strojniski Vestnik-Journal of Mechanical Engineering Pub Date : 2019-11-18 DOI: 10.5545/sv-jme.2019.6350

B. Šarler, T. Dobravec, G. Glavan, V. Hatić, B. Mavrič, R. Vertnik, P. Cvahte, Filip Gregor, M. Jelen, M. Petrović

{"title":"Multi-Physics and Multi-Scale Meshless Simulation System for Direct-Chill Casting of Aluminium Alloys","authors":"B. Šarler, T. Dobravec, G. Glavan, V. Hatić, B. Mavrič, R. Vertnik, P. Cvahte, Filip Gregor, M. Jelen, M. Petrović","doi":"10.5545/sv-jme.2019.6350","DOIUrl":"https://doi.org/10.5545/sv-jme.2019.6350","url":null,"abstract":"This paper represents an overview of the elements of the user-friendly simulation system, developed for computational analysis and optimization of the quality and productivity of the electromagnetically direct-chill cast semi-products from aluminium alloys. The system also allows the computational estimation of the design changes of the casting equipment. To achieve this goal, the electromagnetic and the thermofluid process parameters are coupled to the evolution of Lorentz force, temperature, velocity, concentration, strain and stress fields as well as microstructure evolution. This forms a multi-physics and multi-scale problem of great complexity, which has not been demonstrated before. The macroscopic fluid mechanics, solid mechanics, and electromagnetic solution framework is based on local strong-form meshless formulation, involving the radial basis functions and monomials as trial functions, and local collocation or weighted least squares approximation. It is coupled to the micro-scale by incorporating the point automata solution concept. The entire macro-micro solution concept does not require meshing and space integration. The solution procedure can be easily and efficiently automatically adapted in node redistribution and/or refinement sense, which is of utmost importance when coping with fields exhibiting sharp gradients, which occur in the phase-change problems. The simulation system is coded from scratch in modern Fortran. The elements of the experimental validation of the system and the demonstration of its use for round billet casting in IMPOL Aluminium Industry are shown.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"1 1","pages":"658-670"},"PeriodicalIF":1.7,"publicationDate":"2019-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72759450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Pulses on Demand in Fibre and Hybrid Lasers 光纤和混合激光器的脉冲需求

IF 1.7 4区工程技术

Strojniski Vestnik-Journal of Mechanical Engineering Pub Date : 2019-11-18 DOI: 10.5545/sv-jme.2019.6352

R. Petkovšek, V. Agrež, J. Petelin, Luka Černe, U. Bünting, Boštjan Podobnik

引用次数: 2

The Effect of Population Ageing on Heating Energy Demand on National Level: A Case Study of Slovenia 人口老龄化对国家供暖能源需求的影响:以斯洛文尼亚为例

IF 1.7 4区工程技术

Strojniski Vestnik-Journal of Mechanical Engineering Pub Date : 2019-11-18 DOI: 10.5545/sv-jme.2019.6394

Žiga Lampret, Gorazd Krese, M. Prek

引用次数: 1

Distributed Manufacturing Systems with Digital Agent 数字代理的分布式制造系统

IF 1.7 4区工程技术

Strojniski Vestnik-Journal of Mechanical Engineering Pub Date : 2019-11-18 DOI: 10.5545/sv-jme.2019.6331

N. Herakovič, H. Zupan, M. Pipan, Jernej Protner, M. Šimic

引用次数: 10

Effects of multiple factors on water hammer induced by a large flow directional valve 多因素对大流量换向阀水锤的影响

IF 1.7 4区工程技术

Strojniski Vestnik-Journal of Mechanical Engineering Pub Date : 2018-05-23 DOI: 10.5545/SV-JME.2017.5109

Li Yaoyao, Lian Zisheng, Jiling Feng, Yu Hongbing, Zhao Ruihao

{"title":"Effects of multiple factors on water hammer induced by a large flow directional valve","authors":"Li Yaoyao, Lian Zisheng, Jiling Feng, Yu Hongbing, Zhao Ruihao","doi":"10.5545/SV-JME.2017.5109","DOIUrl":"https://doi.org/10.5545/SV-JME.2017.5109","url":null,"abstract":"© 2018 Journal of Mechanical Engineering. All rights reserved. The flow gain of the large flow poppet directional valve presently used on hydraulic-powered support is large, so water hammer occurs easily when the poppet valve closes. Thus, the hydraulic system, its components, and human safety are seriously threatened. To solve this problem, a plane-sealed large flow directional valve with different throttle windows, which must be taken into consideration when the mathematical model is established, is designed. The effects of spring stiffness and the shape of the throttle window on the hydraulic shock induced by the valve are analysed with the combination of simulation and experiments. It is obvious that the bigger the spring stiffness is, the greater the water hammer is produced. When the spring stiffness continues to increase, the valve becomes instable and causes much stronger water hammer. The area gains of the valves with different throttle windows (round type, triangular type, rectangle combined type) are different, and the corresponding instances of water hammer differ accordingly. Compared with the common round throttle window, the triangular window produces the lowest shock. Furthermore, the effects of the closing time and the type of control curve of the main valve on the water hammer are explored. It is helpful for the proportional control of the large flow water directional valve in the future. This study provides valuable references for the design of the large flow water valve and the corresponding control of water hammer.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"8 1","pages":"329-338"},"PeriodicalIF":1.7,"publicationDate":"2018-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84182785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8