Transactions of FAMENA最新文献_第7页

Vibration Attenuation Mechanism of the Rotor System with Anisotropic Support Stiffness 支承刚度各向异性转子系统的减振机理

IF 1.3 4区工程技术

Transactions of FAMENA Pub Date : 2021-03-05 DOI: 10.21278/TOF.451017220

Sheng-Cai Li, L. Zheng

{"title":"Vibration Attenuation Mechanism of the Rotor System with Anisotropic Support Stiffness","authors":"Sheng-Cai Li, L. Zheng","doi":"10.21278/TOF.451017220","DOIUrl":"https://doi.org/10.21278/TOF.451017220","url":null,"abstract":"Using the one-dimensional finite element method, the dynamic behaviour of a doubledisk rotor system with anisotropic supports is studied in this paper. First, the natural frequencies, whirl state and unbalance response of the rotor system are analysed. Then, the vibration attenuation mechanism of the rotor system under the effect of bearing damping and accelerating rotor is discussed in detail. The research results show that stiffness anisotropy makes natural frequency lines of the rotor system tend to diverge from each other. The damping in bearings not only decreases the amplitude of forward and backward whirls but also reduces the spin speed range of backward whirl. The whirl orbit of the rotor system approximates a straight line at the spin speeds near the critical point of the backward and forward whirls. For the unbalance response of the rotor system with anisotropic supports, the forward natural frequency dominates in the direction of the strong stiffness axis, while the unbalance response in the direction of the weak stiffness axis is mainly affected by the backward natural frequency. Increasing the run-up acceleration can decrease the amplitude of backward and forward whirls, but it cannot reduce the spin speed range of backward whirl.","PeriodicalId":49428,"journal":{"name":"Transactions of FAMENA","volume":"45 1","pages":"129-144"},"PeriodicalIF":1.3,"publicationDate":"2021-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43321838","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: 0

A Bayesian Conjugate Model for the Estimation of Friction Intensity 摩擦强度估计的贝叶斯共轭模型

IF 1.3 4区工程技术

Transactions of FAMENA Pub Date : 2021-03-05 DOI: 10.21278/TOF.451026321

S. Perišić, J. Barle, Predrag Đukić, H. Wolf

引用次数: 0

A Model for Maintenance Planning and Process Quality Control Optimization Based on EWMA and CUSUM Control Charts 基于EWMA和CUSUM控制图的维修计划和过程质量控制优化模型

IF 1.3 4区工程技术

Transactions of FAMENA Pub Date : 2021-03-05 DOI: 10.21278/TOF.451021920

Mohammed A. Noman, Adel M. Al-Shayea, E. A. Nasr, Husam Kaid, A. Al-Ahmari, A. Kamrani, Haitham A. Mahmoud

{"title":"A Model for Maintenance Planning and Process Quality Control Optimization Based on EWMA and CUSUM Control Charts","authors":"Mohammed A. Noman, Adel M. Al-Shayea, E. A. Nasr, Husam Kaid, A. Al-Ahmari, A. Kamrani, Haitham A. Mahmoud","doi":"10.21278/TOF.451021920","DOIUrl":"https://doi.org/10.21278/TOF.451021920","url":null,"abstract":"The performance of a production system is highly dependent on the smooth operation of various equipment and processes. Thus, reducing failures of the equipment and processes in a cost-effective manner improves overall performance; this is often achieved by carrying out maintenance and quality control policies. In this study, an integrated optimization method that addresses both maintenance strategies and quality control practices is proposed using an exponentially weighted moving average (EWMA) chart, in which both corrective and preventive maintenance policies are considered. The integrated model has been proposed to find optimal decision variables of both the process quality decision parameters and the optimal interval of preventive maintenance (i.e., Ns, Hs, L, λ, and t ) to result in overall optimal expected hourly total system costs. A case study is then utilized to investigate the impact of cost criteria on the proposed integrated model and to compare the proposed model with a model using the cumulative sum (CUSUM) control chart. The improved model outputs indicate that there is a reduction of 34.6% in the total expected costs compared with those of the other model using the CUSUM chart. Finally, an analysis of sensitivity to present the effectiveness of the model parameters and the main variables in the overall costs of the system is provided.","PeriodicalId":49428,"journal":{"name":"Transactions of FAMENA","volume":"45 1","pages":"0-0"},"PeriodicalIF":1.3,"publicationDate":"2021-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43946467","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

Results of Heat Transfer Coefficient Estimation during the Quenching of Cylindrical Samples in Aqueous Solutions 圆柱形试样在水溶液中淬火时的传热系数估算结果

IF 1.3 4区工程技术

Transactions of FAMENA Pub Date : 2021-02-23 DOI: 10.21278/TOF.SI1008421

Š. Behrem, B. Hrnjica

{"title":"Results of Heat Transfer Coefficient Estimation during the Quenching of Cylindrical Samples in Aqueous Solutions","authors":"Š. Behrem, B. Hrnjica","doi":"10.21278/TOF.SI1008421","DOIUrl":"https://doi.org/10.21278/TOF.SI1008421","url":null,"abstract":"Summary The paper presented the results of the heat transfer coefficient estimation in the process of two-dimensional axially symmetric quenching of cylindrical steel samples in aqueous 40  C solutions. One aqueous solution had 5% and the other one 25% of Aquatensid BW. Such solutions allow the rate of cooling of steel quenching less than the one in clean water, and higher than the one in thermal oils. The experimental setup consisted of quenching three dimensionally different cylindrical probes into two different quenchants. The position of the thermocouples inside each probe, the aqueous solution streaming around the probe and the construction of the cooling bath conditioned the thermodynamic setting of the problem. The mathematical setting of the problem was based on thermodynamic assumption of two-dimensional axially symmetric, nonlinear and nonstationary heat conduction. The position of the thermocouples conditioned the inverse way of the problem solving and it led to an approximate estimation of an unknown heat transfer coefficient. During the task solving the compute model used the experimental results of the temperature measurements for the minimisations of the square deviation between the calculated and measured temperatures in one position and moment of time. The analysis of the obtained results during the quenching of cylindrical probes in aqueous solutions was compared to the results obtained when quenching in","PeriodicalId":49428,"journal":{"name":"Transactions of FAMENA","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47994425","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: 2

Wear Rate Evaluation of Sol-Gel TiO2-ZrO2 Films by Quantitative Depth Profile Analysis 溶胶-凝胶TiO2-ZrO2薄膜磨损率定量深度剖面分析

IF 1.3 4区工程技术

Transactions of FAMENA Pub Date : 2021-02-23 DOI: 10.21278/tof.444016120

K. Grilec, L. Ćurković, I. Žmak

引用次数: 1

Numerical Investigation of Cover Plate Configurations Effect on Thermal Characteristics of a Polymer Solar Collector 盖板形态对聚合物太阳能集热器热特性影响的数值研究

IF 1.3 4区工程技术

Transactions of FAMENA Pub Date : 2021-02-23 DOI: 10.21278/TOF.SI1009821

P. Filipović, D. Dović, I. Horvat, B. Ranilović

{"title":"Numerical Investigation of Cover Plate Configurations Effect on Thermal Characteristics of a Polymer Solar Collector","authors":"P. Filipović, D. Dović, I. Horvat, B. Ranilović","doi":"10.21278/TOF.SI1009821","DOIUrl":"https://doi.org/10.21278/TOF.SI1009821","url":null,"abstract":"COLLECTOR Summary This paper presents numerical analysis on influence of different configurations on thermal performances of a polymer solar collector. In the first step two configurations including single cover plate and honeycomb cover plate are investigated. Results showed that collector with single cover plate is more efficient than collector with honeycomb cover plate at lower reduced temperature values. Honeycomb cover plate behaves like insulator, increasing overall collector top resistance to heat loss which results in higher thermal efficiency at higher reduced temperature values. This also leads to higher temperatures at stagnation regimes. Also, in this paper two passive overheating protection based on natural convection are examined. Channels inside honeycomb cover plate can be connected to channels inside absorber plate allowing for air to flow inside collector. Three different channel widths are considered 4.25, 10, and 20 mm. With such passive method, it is possible to reduce average absorber temperature up to ~20°C. Second overheating protection uses additional channel below the absorber plate allowing the flow of ambient air. With this method it is possible to reduce temperatures up to ~50°C but it also causes high temperature gradient, 50°C/m of collector length which can potentially result in deformation of polymer solar collector. Present work is a part of the research focused at development of a low-cost polymer solar collector that operates in a drain back","PeriodicalId":49428,"journal":{"name":"Transactions of FAMENA","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44330007","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: 0

Infrared Thermography as a Prediction Tool for the Irrigation Requirement in Agriculture 红外热像仪在农业灌溉需求预测中的应用

IF 1.3 4区工程技术

Transactions of FAMENA Pub Date : 2021-02-23 DOI: 10.21278/TOF.SI1006621

B. Ranilović, Alen Cukrov, I. Boras, S. Švaić, M. Zovko

引用次数: 0

The Model Prediction of Life Cycle Ownership Costs of Special Motor Vehicles 特种机动车辆全寿命拥有成本的模型预测

IF 1.3 4区工程技术

Transactions of FAMENA Pub Date : 2021-01-22 DOI: 10.21278/tof.444004719

J. Furch

{"title":"The Model Prediction of Life Cycle Ownership Costs of Special Motor Vehicles","authors":"J. Furch","doi":"10.21278/tof.444004719","DOIUrl":"https://doi.org/10.21278/tof.444004719","url":null,"abstract":"The paper deals with the prediction of life cycle costs related to special motor vehicles. In the first part, there is an analysis of the applied commercial software programs used for calculating and predicting the life cycle cost of vehicles. Next, there is a description of risks which might occur when calculating the life cycle cost and of the possible risk management. In the second part of the paper it is suggested that the motor vehicle life cycle cost can be predicted based on accurate data which are generally difficult to obtain, e.g. failure intensity z(t) or mean time between failures (MTBFs) used for calculating the cost after maintenance. The final part includes a proposal for the prediction of the ownership life cycle cost which consists of the operating and maintenance costs of special motor vehicles. This proposal is based on the company logistic information system, which at regular intervals assesses special vehicle life cycle cost during operation and maintenance. Under special motor vehicles here we understand the vehicles which are equipped with a chassis and a special vehicle superstructure which consumes operation units and on which maintenance is performed. Such vehicles are used in the construction or agricultural industry as well as in the military environment. The paper focuses on the design of a prediction model of the ownership life cycle cost of the military environment, where a relevant military logistic information system is used.","PeriodicalId":49428,"journal":{"name":"Transactions of FAMENA","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47981149","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: 1

Milling Machine Error Modelling and Analysis in the Machining of Circular-Arc-Tooth-Trace Cylindrical Gears 圆弧齿迹圆柱齿轮加工中的铣床误差建模与分析

IF 1.3 4区工程技术

Transactions of FAMENA Pub Date : 2021-01-22 DOI: 10.21278/tof.444009419

Yang Wu, Li Hou, Dengqiu Ma, W. Yongqiao, Lan Luo

{"title":"Milling Machine Error Modelling and Analysis in the Machining of Circular-Arc-Tooth-Trace Cylindrical Gears","authors":"Yang Wu, Li Hou, Dengqiu Ma, W. Yongqiao, Lan Luo","doi":"10.21278/tof.444009419","DOIUrl":"https://doi.org/10.21278/tof.444009419","url":null,"abstract":"GEARS Summary This paper is to study errors of a milling machine used for the machining of Circular-Arc-Tooth-Trace (CATT) cylindrical gears. A topological structure model of the milling machine is established using the lower numbered body array approach. Coordinate transformation matrices between adjacent parts of the milling machine are set up by the D-H homogeneous transformation matrix. Based on the topological structure model and transformation matrices, a comprehensive error model of a milling machine used for the machining of CATT gears is established. According to the error model, the angle errors of the milling point are linear combinations of the angle errors of moving parts, while the displacement errors of the milling point are related to displacement errors, the angle errors of moving parts, the adjustment parameters of machine tools, and the geometric parameters of the gear. Finally, the influence of the errors of the cutter head on the milling point errors in the machining of CATT gears are discussed. The research can provide a theoretical basis for the error analysis, precision design, and the geometric error compensation of a milling machine used for CATT gear","PeriodicalId":49428,"journal":{"name":"Transactions of FAMENA","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43793193","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: 5

Contact Stress Prediction Model for Variable Hyperbolic Circular Arc Gear Based on the Optimized Kriging-Response Surface Model 基于优化Kriging响应面模型的变双曲圆弧齿轮接触应力预测模型

IF 1.3 4区工程技术

Transactions of FAMENA Pub Date : 2021-01-22 DOI: 10.21278/tof.444011819

Zhang Qi, Wen Guang, Luo Lan, T. Rui

{"title":"Contact Stress Prediction Model for Variable Hyperbolic Circular Arc Gear Based on the Optimized Kriging-Response Surface Model","authors":"Zhang Qi, Wen Guang, Luo Lan, T. Rui","doi":"10.21278/tof.444011819","DOIUrl":"https://doi.org/10.21278/tof.444011819","url":null,"abstract":"In order to study the influence of design parameters (pressure angle, tooth width, tooth line radius, modulus, and moment) on contact stress of variable hyperbolic circular arc gear (VHCAG) and to obtain the best manufacturing parameters, The Kriging-Response Surface Model, a hybrid surrogate model with adaptive quantum particle swarm optimization (QPSO) algorithm was proposed to establish the expression prediction model for the relation between design parameters and contact stress. An intelligent quantum particle swarm optimization algorithm based on adaptive weight and natural selection is proposed to optimize the parameters of Gaussian variation function of the kriging surrogate model to improve its fitting accuracy. The global search ability of quantum particles is improved, and the accuracy and stability of the algorithm are improved by adjusting the weight of quantum particles adaptively and by optimizing the elimination iteration process, and the response relationship between design parameters and contact stress was established. The binomial response surface model of gear design parameters and contact stress is established based on the output obtained through the improved kriging model; this simplifies the complex expression of the kriging model. The effects of parameters and their cross-terms on contact stress are analysed based on the contact stress prediction model established by using the optimized Kriging-Response Surface Model hybrid surrogate model. The hybrid Kriging-Response Surface Model surrogate model lays a foundation for the research on the reliability and robust optimization of cylindrical gears with variable hyperbolic arc tooth profile.","PeriodicalId":49428,"journal":{"name":"Transactions of FAMENA","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49537297","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: 2