Journal of Mechanical Engineering and Sciences最新文献

{"title":"The Analysis of Dual Axis Solar Tracking System Controllers Based on Adaptive Neural Fuzzy Inference System (ANFIS)","authors":"S. Z. Mohammad Noor","doi":"10.24191/jmeche.v20i2.22061","DOIUrl":"https://doi.org/10.24191/jmeche.v20i2.22061","url":null,"abstract":"Artificial intelligence is commonly used in Photovoltaic (PV) control systems. Adaptive Neural Fuzzy Inference System (ANFIS) is one of the intelligent strategies that can be employed in the system controller. ANFIS technique shows high accuracy as it involved several processes which are the Fuzzy layer, Fuzzy Rule layer, Normalization layer, and Output Membership layer. The main objective of the proposed work is to model the dual-axis solar tracker using MATLAB software by utilizing the ANFIS technique, hence improving the performance of the solar system. The data used for training and testing are elevation angle and azimuth angle. 80% of the data is used for training and another 20% for testing in order to predict the solar radiation toward PV panels. A different set of input membership functions (MFs) is used in the system, which are Five MFs, Ten MFs, and Fifteen MFs. These MF are simulated to produce the best prediction of solar radiation. The results showaverage error gained for both training and testing data and minimum error indicates the accuracy of the predicted angle of dual axis solar tracker. In the finding, overall results show a good correlation between the actual and prediction value with 15 input MFs as it produced the lowest error value.","PeriodicalId":16166,"journal":{"name":"Journal of Mechanical Engineering and Sciences","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77431756","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}

{"title":"Simulation of the Erosion-Corrosion Destruction Process of Steam Turbine Low-Pressure Cylinder Blades","authors":"O. Shubenko, A. Tarelin","doi":"10.15407/pmach2023.01.029","DOIUrl":"https://doi.org/10.15407/pmach2023.01.029","url":null,"abstract":"This paper is devoted to the important problem of creating a method for predicting the intensity of erosion-corrosion destruction of the working blades material of low-pressure stages of powerful steam turbines, considering the complex physical processes that accompany the emergence, transformation of erosion-hazardous droplets and their interaction with elements of the flow path. The features of the construction of some existing erosion models are considered. The model that is developed at the Institute of Mechanical Engineering Problems of the National Academy of Sciences of Ukraine and based on a deterministic-statistical approach to its creation is analyzed in detail. The calculations performed during the research showed a satisfactory coincidence with the results of experimental tests by various authors, obtained on droplet impact stands, which contributed to the successful use of the model in creating a comprehensive method of predicting the wear of working blades. To do this, it was supplemented by the method of determining the parameters of the erosive environment based on the droplet movement equation, taking into account the size distribution law. Along with that, it is shown that the considered model, although it allows to carry out fairly accurate prediction of the development of erosive wear at the modern level, has difficulties in its construction due to the need to identify it from the data of full-scale experiments, the number of which is limited. It has been established that one of the important reasons for the discrepancies that arise is the failure to include of the electrophysical component of the processes occurring in a two-phase flow. In this regard, the results of comprehensive studies of steam electrization and its influence on the working processes of wet steam turbines are considered. It is shown that the change in the properties of the working medium as a functional erosive medium as a result of electrification causes a significant increase (relative to neutral wet steam) of electrochemical processes. At the same time, the kinetics of the damage accumulation to the metal surface layer changes due to the joint occurrence of several negative processes: droplet impact influence; electrochemical processes caused by mechanical and structural and chemical heterogeneity of the surface; hydrogen absorption; changes in mechanical properties under the electric field influence. It was noted that the contribution of hydrogen absorption to changes in mechanical properties is the greatest. According to a preliminary assessment, the complex negative droplet impact and electrophysical influence on the metal surface reduces the incubation period and intensifies the erosion-corrosion process by approximately 2 times","PeriodicalId":16166,"journal":{"name":"Journal of Mechanical Engineering and Sciences","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88134960","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}

{"title":"Determination of Elements Reliability for Power Plants Based on Internal Combustion Engines by Lowest Residual Entropy Method","authors":"S. Zaichenko, K. Pochka, Yurii O. Romasevych, V. Shalenko, R. Kulish, M. Balaka","doi":"10.15407/pmach2023.01.039","DOIUrl":"https://doi.org/10.15407/pmach2023.01.039","url":null,"abstract":"The selection technique of diagnostic parameters for the creation of fault detection system of autonomous electric power sources based on gasoline and diesel engines is given in the paper. An analysis of the design features for autonomous electric power sources based on internal combustion engines, which are the most common on the Ukrainian market, was carried out. Thanks to this, a logical model of the research object, which establishes the relation between the main structural elements of the system and determines the possible states of the system, was developed. The effect of fault state initiation for each element on the other system elements was analyzed. An informative criterion – Shannon information entropy is proposed to determine the finite number of diagnostic parameters among the infinite number of possible combinations for physical parameters that characterize the system. The equal-probable cases of exit from operational state of each system elements are considered. The residual entropies of the system at the fault state for one of the autonomous power sources assembly are determined, having applied the concept of Shannon information entropy. The residual entropy value is the informative criterion. The application of this criterion allowed to determine the system elements that most effectively reduce the system uncertainty degree. Based on the residual entropy values, the system assemblies, the state of which should be primarily monitored by diagnostic system, are selected. The diagnostic parameters are determined for such elements, and the ways to obtain them are given","PeriodicalId":16166,"journal":{"name":"Journal of Mechanical Engineering and Sciences","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90553917","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}

{"title":"Analysis of the Stress State for a Layer with Two Incut Cylindrical Supports","authors":"V. Miroshnikov, Oleksandr B. Savin, Mykhailo M. Hrebennikov, V. F. Demenko","doi":"10.15407/pmach2023.01.015","DOIUrl":"https://doi.org/10.15407/pmach2023.01.015","url":null,"abstract":"The stress state of a homogeneous isotropic layer under the action of a spatial static external load is studied. Two circular cylindrical supports are cut into the body of the layer parallel to its borders. The supports and body of the layer are rigidly coupled. The spatial problem theory of elasticity is solved using the analytical-numerical generalized Fourier method. The layer is considered in the Cartesian coordinate system, the supports are considered in the local cylindrical coordinates. Stresses are set on the upper and lower surfaces of the layer. The supports are considered as cylindrical cavities in a layer with zero displacements set on their surfaces. Satisfying the boundary conditions on the upper and lower surfaces of the layer, as well as on the cylindrical surfaces of the cavities, a system of infinite integro-algebraic equations, which are further reduced to linear algebraic ones, is obtained. An infinite system is solved by the reduction method. In the numerical studies, the parameters of integration oscillatory functions are analyzed, problems at different distances between supports are solved. A unit load in the form of a rapidly decreasing function is applied to the upper boundary between the supports. For these cases, an analysis of the stress state was performed on the surfaces of the layer between the supports and on the cylindrical surfaces in contact with the supports. The numerical analysis showed that when the distance between the supports increases, the stresses σx on the lower and upper surfaces of the layer and the stresses τρφ on the surfaces of the cavities increase. The use of the analytical-numerical method made it possible to obtain a result with an accuracy of 10-4 for stress values from 0 to 1 at the order of the system of equations m=6. As the order of the system increases, the accuracy of fulfilling the boundary conditions will increase. The presented analytical-numerical solution can be used for high-precision determination of the stress-strain state of the presented problems type, as well a reference for problems based on numerical methods","PeriodicalId":16166,"journal":{"name":"Journal of Mechanical Engineering and Sciences","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87219928","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}

{"title":"Aeroelastic Characteristics of Rotor Blades of Last Stage of a Powerful Steam Turbine","authors":"Liubov V. Kolodiazhna, Y. Bykov","doi":"10.15407/pmach2023.01.006","DOIUrl":"https://doi.org/10.15407/pmach2023.01.006","url":null,"abstract":"Blades of powerful steam turbines are subjected to significant unsteady loads, which, in some cases, can lead to the appearance of self-excited oscillations or auto-oscillations. These fluctuations are extremely dangerous and negatively affect the life time of the blading. When developing new or upgrading existing turbine stages, it is necessary to carry out research on the aeroelastic behavior of the rotor blades. As a result of the modernization of a low-pressure cylinder of a 1000 MW steam turbine, the length of the rotor blades of the last stage increased to 1650 mm. In this regard, a numerical analysis of the aeroelastic characteristics of the last-stage rotor blades in the nominal operation mode was carried out. The analysis used the method of solving the coupled problem of unsteady aerodynamics and elastic blade vibrations, which allows the prediction of the amplitude-frequency spectrum of unsteady loads and blade vibrations in a viscous gas flow. The paper presents the results of numerical analysis of aeroelastic characteristics of the last stage rotor blades both for the mode of controlled harmonic oscillations with a given amplitude and inter-blade phase shift, and for the mode of coupled oscillations of the blades under influence of unsteady aerodynamic forces. The results of the simulation of coupled oscillations of blades for the first five natural forms are presented in the form of the time distribution of displacement of the blade peripheral cross-section, as well as the time distribution of forces and moments acting on the peripheral cross-section. The corresponding amplitude-frequency spectra of displacements and loads in the peripheral section are also given. The results of the calculations showed a positive damping of oscillations, the absence of flutter and auto-oscillations for the first five natural forms of oscillations of the blades in the nominal operation mode of the steam turbine","PeriodicalId":16166,"journal":{"name":"Journal of Mechanical Engineering and Sciences","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86153256","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}

{"title":"Use of Logarithmic Decrement of Oscillation Damping for Prediction of the Aviation Structures Service Life","authors":"Mykhailo M. Hrebennikov, Oleksandr H. Dibir, Anatolii O. Kyrpikin, Mykola I. Pekelnyi","doi":"10.15407/pmach2023.01.023","DOIUrl":"https://doi.org/10.15407/pmach2023.01.023","url":null,"abstract":"Problem of predicting the residual service life of airplanes and helicopters is highly relevant for flight safety. In this paper, on the basis of the conducted research on the change of mechanical characteristics during materials fatigue accumulation, it is proposed to control the service life by changing the dissipative characteristics. In case of fatigue damage, the accumulative logarithmic decrement of oscillation damping δ increases to the limit maximum value δm, which corresponds to the critical length of the main fatigue crack, which leads to failure. The limit value δm can be set depending on the amount of energy spent on the development of the main fatigue crack, taking into account the dangerous part of the consumed energy. With the accumulation of fatigue damage, the growth of logarithmic decrement occurs at the expense of energy expenditure for the growth of fatigue cracks and internal friction. This is taken into account by the coefficient α, which allows to allocate a dangerous part of the energy that goes into the development of a main fatigue crack. The problem of durability prediction consists of two stages. At first, it is needed to determine δm for the critical crack length. Then, based on the two values of logarithmic decrement at the corresponding load cycles, the number of cycles to failure – to the critical length of the crack – is predicted by the Peris formula","PeriodicalId":16166,"journal":{"name":"Journal of Mechanical Engineering and Sciences","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78952889","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}

{"title":"The effect of Aegle marmelos shell particles volume fraction on hardness, toughness, and wear rate of epoxy matrix composites as motorcycle brake pads","authors":"Heri Yudiono, M.T.N. Fuad","doi":"10.15282/jmes.17.1.2023.4.0738","DOIUrl":"https://doi.org/10.15282/jmes.17.1.2023.4.0738","url":null,"abstract":"The utilization of Aegle marmelos shell particles is not optimal yet. Composite brake pads are currently being developed because they are eco-friendly and heat resistant compared to non-asbestos brake pads. This research attempt to analyze the volume fraction of Aegle marmelos shell particles on the measure of hardness, toughness, and wear of epoxy matrix composites as an alternative material for motorcycle brake pads. The design of this research uses a true experimental design with a posttest-only design type, there is an experimental group (composite) and a control group (Indoparts brand brake pads). The results show the most optimal measure is found in volume 30% with a hardness measure of 79.5 HRB, toughness 0.01312 J/mm2, wear 2.008 x 10-6 mm2/kg. It shows that the more particles volume, the composite strength will increase. This measure is closest to the measure of the Indoparts motorcycle brake pads. Therefore, Aegle marmelos shell particles composite can be recommended as an alternative material for motorcycle brake pads.","PeriodicalId":16166,"journal":{"name":"Journal of Mechanical Engineering and Sciences","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43092137","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}

{"title":"The impact of the wall insulation material and variable refrigerant flow system on building energy consumption and cost","authors":"Hamza Shaikh, R. Memon, S. Qureshi, Asad A. Shaikh, S. Noonari","doi":"10.15282/jmes.17.1.2023.8.0742","DOIUrl":"https://doi.org/10.15282/jmes.17.1.2023.8.0742","url":null,"abstract":"The use of VRF system and insulation in building envelope are both considered as promising option to reduce energy consumption of a building. This study analysis energy saving potential of VRF system and building insulation using modelling and simulation of a typical office building. The model office building is simulated with the weather of Hyderabad, Sindh, Pakistan using EnergyPlus building simulation software. The simulation cases include conventional and VRF air conditioning systems with and without insulation to evaluate and compare the annual cooling and energy savings and payback period. Results showed that by replacing conventional air conditioner with VRF AC electrical power can be reduced by 42-45%. It is also noted that Cellulose, expanded polystyrene, extruded polystyrene and polyurethane insulations can save around 49.5, 51.4, 51.6, and 54.54% of electricity, respectively. In the case VRF air conditioner used with Cellulose, expanded polystyrene, extruded polystyrene and polyurethane insulation may reduce electricity consumption by 66.5, 67.4, 67.5 and 68.9 %, respectively. The payback period varies from 7 to 15 months. However, cellulose with VRF air conditioner has the least payback period of around 7 months. The longest payback period of around 15 months was noted for the un-insulated office building with VRF air conditioner. Despite having longer payback period, the combination of polyurethane insulation with VRF air conditioning system is the most efficient combination.","PeriodicalId":16166,"journal":{"name":"Journal of Mechanical Engineering and Sciences","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47430659","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}

{"title":"Evaluation of welding-induced residual stress and distortion in A-TIG welding of duplex stainless steel","authors":"A. Siyavoshi, S. Shakhesi, M. Afshar, M. Hashemzadeh, M. Noghabi","doi":"10.15282/jmes.17.1.2023.3.0737","DOIUrl":"https://doi.org/10.15282/jmes.17.1.2023.3.0737","url":null,"abstract":"Applying non-uniform heat in welding causes residual stress and distortion, which affects the life of components. In the present study, the residual stress and distortion of Duplex 2205 stainless steel in A-TIG welding were investigated numerically and experimentally. The optimal welding parameters for highest penetration depth in welded samples were obtained experimentally. Uncoupled thermal-mechanical analysis using ABAQUS 2017 software has been done. Goldak's parameters were measured by empirical tests. The results include simulation diagrams of four samples consisting of the optimal sample without flux powder and three samples with the highest penetration depth. The simulation results show that the sample without flux has a higher maximum temperature and lower welding-induced distortions. The efficiency used in this research changes using and not using powder; it is concluded that, in similar conditions in A-TIG welding, fewer values of parameters are needed to achieve the appropriate result comparing conventional TIG. The efficiency of workpieces with flux should be considered about 20% lower to have similar results to the conventional TIG. The numerical modeling results showed a good agreement with experimental data both for temperature distribution and welding-induced residual stress and distortion. The distortion in the pieces with conventional TIG welding has increased to 11% at the farthest point from the welding line. The error obtained from comparing the results in residual stress is between 12 and 34%.","PeriodicalId":16166,"journal":{"name":"Journal of Mechanical Engineering and Sciences","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41643433","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}

{"title":"Finite element analysis of a stemmed hip prosthesis to reduce stress shielding in the proximal femur","authors":"Oliver Bliss, JG Swadener, Gillian Pierce, Iham F. Zidane","doi":"10.15282/jmes.17.1.2023.5.0739","DOIUrl":"https://doi.org/10.15282/jmes.17.1.2023.5.0739","url":null,"abstract":"A finite element analysis (FEA) was performed on four prosthesis designs with different internal structures within identical prosthetic stem geometry. A novel hexagonal structure akin to one of the strongest structures in nature is used internally in the stem. The hip implant designs were then analyzed for an applied force of 3227 N. This force was selected because a typical gait cycle generates forces up to 3.87 times the body weight in the hip joint. The FEA results were compared for various stem designs with rectangular cross-sections. The design objective for a hip stem is to have a low stiffness and stress shielding together with a very high fatigue life. The stress shielding reduction of the prothesis was measured by observing the change in stress distribution in a FE femur model before and after implant. Stress shielding was quantified volumetrically, and the surface stresses of the femur were considered to appraise any increased risk of periprosthetic fracture due to increased bone stress. Subsequently, the stems that had the lowest stress shielding models were then optimized. Results showed a reduction of stiffness of 18%, and a reduction in stress shielding of 30% compared to a solid stem.","PeriodicalId":16166,"journal":{"name":"Journal of Mechanical Engineering and Sciences","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44974662","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}