In this article, we propose a technique based on modified double integral transforms used to solve certain equations of materials science, namely Benney–Luke (BL) and singular pseudo-hyperbolic (SP-H) equations. We have established some analytical results. This method can provide accurate one-step solutions, although the equations used may exhibit a singularity in the initial conditions. Some numerical examples have been discussed for illustration and to show the effectiveness of the technique for certain types of equations. We have developed an exact solution in just one step, whereas other approaches require several stages to succeed in a particular solution, making the proposed strategy particularly successful and straightforward to apply to various varieties of the B–L and SP-H equations.
{"title":"Modified Integral Transform for Solving Benney-Luke and Singular Pseudo-Hyperbolic Equations","authors":"T. Elzaki, M. Chamekh, Shams A. Ahmed","doi":"10.2478/ama-2024-0018","DOIUrl":"https://doi.org/10.2478/ama-2024-0018","url":null,"abstract":"\u0000 In this article, we propose a technique based on modified double integral transforms used to solve certain equations of materials science, namely Benney–Luke (BL) and singular pseudo-hyperbolic (SP-H) equations. We have established some analytical results. This method can provide accurate one-step solutions, although the equations used may exhibit a singularity in the initial conditions. Some numerical examples have been discussed for illustration and to show the effectiveness of the technique for certain types of equations. We have developed an exact solution in just one step, whereas other approaches require several stages to succeed in a particular solution, making the proposed strategy particularly successful and straightforward to apply to various varieties of the B–L and SP-H equations.","PeriodicalId":44942,"journal":{"name":"Acta Mechanica et Automatica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140412597","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}
Abstract Technological advances are contributing to the search for highly efficient energy designs, and increasing interest in compact heat exchangers. Indeed, small channel diameters determine large heat transfer coefficients and condition a significant heat transfer area about the overall volume of the heat exchanger, as well as a smaller amount of refrigerant flowing in the system. Nevertheless, the operating stability and energy efficiency of compact heat exchangers are influenced by two-phase flow structures, which depend on thermal flow parameters. Knowledge of the structures formed during the condensation process is therefore essential for optimising the operation of refrigeration and air-conditioning equipment. This article presents the results from experimental studies of the HFE7100 refrigerant, from the hydrofluorocarbon group, condensation process in mini-channels with hydraulic diameters dh = 2.0 mm, 1.2 mm, 0.8 mm and 0.5 mm. Thermal flow characteristics were determined, and the forming structures of two-phase flow were recorded. The results of visualisation were subjected to morphological image analysis, based on a special algorithm written in MATLAB software. The algorithm makes it possible to determine the void fraction, which is necessary for calculating the vapour quality, as well as the area of vapour bubbles and their number, directionality and length along the x- and y-axes.
摘要 技术的进步促进了对高效能源设计的探索,也增加了人们对紧凑型热交换器的兴趣。事实上,较小的通道直径决定了较大的传热系数,并为热交换器的总体积提供了较大的传热面积,同时也减少了系统中的制冷剂用量。然而,紧凑型热交换器的运行稳定性和能效受到两相流结构的影响,这取决于热流参数。因此,了解冷凝过程中形成的结构对于优化制冷和空调设备的运行至关重要。本文介绍了氢氟碳化合物组中的 HFE7100 制冷剂在水力直径 dh = 2.0 毫米、1.2 毫米、0.8 毫米和 0.5 毫米的微型通道中冷凝过程的实验研究结果。测定了热流特性,并记录了两相流的形成结构。根据用 MATLAB 软件编写的特殊算法,对可视化结果进行了形态图像分析。该算法可以确定计算蒸汽质量所需的空隙率,以及蒸汽气泡的面积、数量、方向性和沿 x 轴和 y 轴的长度。
{"title":"Thermal and Visualisation Study of the HFE7100 Refrigerant Condensation Process","authors":"Tadeush Bohdal, M. Sikora, Karolina Formela","doi":"10.2478/ama-2024-0008","DOIUrl":"https://doi.org/10.2478/ama-2024-0008","url":null,"abstract":"Abstract Technological advances are contributing to the search for highly efficient energy designs, and increasing interest in compact heat exchangers. Indeed, small channel diameters determine large heat transfer coefficients and condition a significant heat transfer area about the overall volume of the heat exchanger, as well as a smaller amount of refrigerant flowing in the system. Nevertheless, the operating stability and energy efficiency of compact heat exchangers are influenced by two-phase flow structures, which depend on thermal flow parameters. Knowledge of the structures formed during the condensation process is therefore essential for optimising the operation of refrigeration and air-conditioning equipment. This article presents the results from experimental studies of the HFE7100 refrigerant, from the hydrofluorocarbon group, condensation process in mini-channels with hydraulic diameters dh = 2.0 mm, 1.2 mm, 0.8 mm and 0.5 mm. Thermal flow characteristics were determined, and the forming structures of two-phase flow were recorded. The results of visualisation were subjected to morphological image analysis, based on a special algorithm written in MATLAB software. The algorithm makes it possible to determine the void fraction, which is necessary for calculating the vapour quality, as well as the area of vapour bubbles and their number, directionality and length along the x- and y-axes.","PeriodicalId":44942,"journal":{"name":"Acta Mechanica et Automatica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139383102","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}
Abstract In this paper, an attempt to estimate the stage of the fatigue process using the Barkhausen noise method is studied. First, microstructural and static tensile tests were carried out and, subsequently, fatigue tests up to failure were conducted. After determination of the material behaviour in the assumed static and dynamic conditions, the interrupted fatigue tests were performed. Each specimen was stressed up to a different number of cycles corresponding to 10%, 30%, 50%, 70% and 90% of fatigue lifetime for the loading conditions considered. In the next step of the experimental programme, the specimens were subjected to the Barkhausen magnetic noise measurements. Various magnetic parameters coming from the rms Barkhausen noise envelopes were determined. The linear relationship betweenthe full-width at half-maximum (FWHM) of the Barkhausen noise envelope and the number of loading cycles to fracture was found. Specimens loaded up to a certain number of cycles were also subjected to a tensile test to assess an influence of fatigue on the fracture features.
{"title":"Fatigue Behaviour of Medium Carbon Steel Assessed by the Barkhausen Noise Method","authors":"K. Makowska, T. Szymczak, Z. Kowalewski","doi":"10.2478/ama-2024-0005","DOIUrl":"https://doi.org/10.2478/ama-2024-0005","url":null,"abstract":"Abstract In this paper, an attempt to estimate the stage of the fatigue process using the Barkhausen noise method is studied. First, microstructural and static tensile tests were carried out and, subsequently, fatigue tests up to failure were conducted. After determination of the material behaviour in the assumed static and dynamic conditions, the interrupted fatigue tests were performed. Each specimen was stressed up to a different number of cycles corresponding to 10%, 30%, 50%, 70% and 90% of fatigue lifetime for the loading conditions considered. In the next step of the experimental programme, the specimens were subjected to the Barkhausen magnetic noise measurements. Various magnetic parameters coming from the rms Barkhausen noise envelopes were determined. The linear relationship betweenthe full-width at half-maximum (FWHM) of the Barkhausen noise envelope and the number of loading cycles to fracture was found. Specimens loaded up to a certain number of cycles were also subjected to a tensile test to assess an influence of fatigue on the fracture features.","PeriodicalId":44942,"journal":{"name":"Acta Mechanica et Automatica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139383399","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}
Abstract The dynamic analysis of complex mechanical systems often requires the application of advanced mathematical techniques. In this study, we present a variation iteration-based solution for a pendulum system coupled with a rolling wheel, forming a combined translational and rotational system. Furthermore, the Lagrange multiplier is calculated using the Elzaki transform. The system under investigation consists of a pendulum attached to a wheel that rolls without slipping on a horizontal surface. The coupled motion of the pendulum and the rolling wheel creates a complex system with both translational and rotational degrees of freedom. To solve the governing equations of motion, we employ the variation iteration method, a powerful numerical technique that combines the advantages of both variational principles and iteration schemes. The Lagrange multiplier plays a crucial role in incorporating the constraints of the system into the equations of motion. In this study, we determine the Lagrange multiplier using the Elzaki transform, which provides an effective means to calculate Lagrange multipliers for constrained mechanical systems. The proposed solution technique is applied to analyse the dynamics of a pendulum with a rolling wheel system. The effects of various system parameters, such as the pendulum length, wheel radius and initial conditions, are investigated to understand their influence on the system dynamics. The results demonstrate the effectiveness of the variation iteration method combined with the Elzaki transform in capturing the complex behaviour of a combined translational and rotational system. The proposed approach serves as a valuable tool for analysing and understanding the dynamics of similar mechanical systems encountered in various engineering applications.
{"title":"The Variational Iteration Method for a Pendulum with a Combined Translational and Rotational System","authors":"Muhammad Amir, Asifa Ashraf, J. A. Haider","doi":"10.2478/ama-2024-0006","DOIUrl":"https://doi.org/10.2478/ama-2024-0006","url":null,"abstract":"Abstract The dynamic analysis of complex mechanical systems often requires the application of advanced mathematical techniques. In this study, we present a variation iteration-based solution for a pendulum system coupled with a rolling wheel, forming a combined translational and rotational system. Furthermore, the Lagrange multiplier is calculated using the Elzaki transform. The system under investigation consists of a pendulum attached to a wheel that rolls without slipping on a horizontal surface. The coupled motion of the pendulum and the rolling wheel creates a complex system with both translational and rotational degrees of freedom. To solve the governing equations of motion, we employ the variation iteration method, a powerful numerical technique that combines the advantages of both variational principles and iteration schemes. The Lagrange multiplier plays a crucial role in incorporating the constraints of the system into the equations of motion. In this study, we determine the Lagrange multiplier using the Elzaki transform, which provides an effective means to calculate Lagrange multipliers for constrained mechanical systems. The proposed solution technique is applied to analyse the dynamics of a pendulum with a rolling wheel system. The effects of various system parameters, such as the pendulum length, wheel radius and initial conditions, are investigated to understand their influence on the system dynamics. The results demonstrate the effectiveness of the variation iteration method combined with the Elzaki transform in capturing the complex behaviour of a combined translational and rotational system. The proposed approach serves as a valuable tool for analysing and understanding the dynamics of similar mechanical systems encountered in various engineering applications.","PeriodicalId":44942,"journal":{"name":"Acta Mechanica et Automatica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139384059","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}
Ewa Kozak-Jagieła, Monika Rerak, W. Zima, Artur Cebula, S. Grądziel, Giorgia Mondino, Richard Blom, L. Nord, Vidar T. Skjervold
Abstract The reduction in CO2 emissions is now a very popular topic. According to the International Energy Agency, CO2 emitted in 2021 was 6% more than that emitted in 2020. Carbon capture and storage (CCS) is gaining popularity as a possible solution to climate change. Experts estimate that industry and power plants will be responsible for 19% of total CO2 emissions by 2050. This paper presents the design of a semi-industrial-scale system for CO2 capture based on the moving bed temperature swing adsorption technology. According to the results of laboratory tests conducted by the SINTEF industry, this technology demonstrates high capture efficiency (>85%). The CO2 capture medium involved in adsorption is activated carbon passing through individual sections (cooling, heating, adsorption), where CO2 is bonded and then released. The heat and mass transfer processes are realised on the developed stand. The heat exchangers use steam and water as the heating/cooling medium. The paper reviews the existing solutions and describes the developed in-house design of heat exchangers that will ensure heat transfer conditions being a trade-off between economic and efficiency-related issues of the CO2 capture process. The designed test stand will be installed in a Polish power plant and is expected to meet the method energy intensity target, set at ≤ 2.7 MJ/kg CO2, with a capture efficiency exceeding 85%. The aim of the work was to develop and solve technical problems that would lead to the construction of a CO2 capture station with parameters mentioned above. This stand uses an innovative method where CO2 is captured by contacting the fluid (gases) with solid particles. The heat exchange associated with the heating and cooling of the adsorbent had to be solved. For this purpose, heat exchangers were designed with high thermal efficiency and to prevent the formation of mounds.
{"title":"The CO2 Capture System with a Swing Temperature Moving Bed","authors":"Ewa Kozak-Jagieła, Monika Rerak, W. Zima, Artur Cebula, S. Grądziel, Giorgia Mondino, Richard Blom, L. Nord, Vidar T. Skjervold","doi":"10.2478/ama-2024-0012","DOIUrl":"https://doi.org/10.2478/ama-2024-0012","url":null,"abstract":"Abstract The reduction in CO2 emissions is now a very popular topic. According to the International Energy Agency, CO2 emitted in 2021 was 6% more than that emitted in 2020. Carbon capture and storage (CCS) is gaining popularity as a possible solution to climate change. Experts estimate that industry and power plants will be responsible for 19% of total CO2 emissions by 2050. This paper presents the design of a semi-industrial-scale system for CO2 capture based on the moving bed temperature swing adsorption technology. According to the results of laboratory tests conducted by the SINTEF industry, this technology demonstrates high capture efficiency (>85%). The CO2 capture medium involved in adsorption is activated carbon passing through individual sections (cooling, heating, adsorption), where CO2 is bonded and then released. The heat and mass transfer processes are realised on the developed stand. The heat exchangers use steam and water as the heating/cooling medium. The paper reviews the existing solutions and describes the developed in-house design of heat exchangers that will ensure heat transfer conditions being a trade-off between economic and efficiency-related issues of the CO2 capture process. The designed test stand will be installed in a Polish power plant and is expected to meet the method energy intensity target, set at ≤ 2.7 MJ/kg CO2, with a capture efficiency exceeding 85%. The aim of the work was to develop and solve technical problems that would lead to the construction of a CO2 capture station with parameters mentioned above. This stand uses an innovative method where CO2 is captured by contacting the fluid (gases) with solid particles. The heat exchange associated with the heating and cooling of the adsorbent had to be solved. For this purpose, heat exchangers were designed with high thermal efficiency and to prevent the formation of mounds.","PeriodicalId":44942,"journal":{"name":"Acta Mechanica et Automatica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139381336","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}
Abstract Titanium and its alloys represent a special class of materials. A density of 4.81 g/cm3, a tensile strength of over 1,200 MPa, a fatigue strength greater than that of steel, a low modulus of elasticity and its self-passivating, inert surface make titanium an ideal material for lightweight structures in aerospace, marine applications, the chemical industry and medical implants. Although titanium is inert in its oxidised state, its nascent surface created in machining reacts with almost everything in its environment, including the tool. Moreover, its poor thermal conductivity results in high thermal stress on the tools. Overall, these properties lead to high wear rates and result in the requirement for finding a particularised solution for processes such as milling that involve the need to overcome such challenges. Such processes therefore require lubricants with well-selected performance additives. However, most of these performance additives are based on mineral oil and thus come from a non-renewable resource. In the presented work, environmental-friendly alternatives to conventional mineral oil-based performance additives were investigated. Due to the working mechanisms of performance additives in machining, this work focusses on sulphur- and phosphorus-containing polysaccharides and proteins from microalgae. It has been successfully shown that lubricants using extracts from microalgae as performance additives can be used for high-speed milling (HSC) of TiAl6V4. The investigated extracts were able to reach the performance level of conventional additives in terms of tool lifetime and wear. The results obtained show that appropriate alternatives to mineral oil-based additives exist from renewable raw-material sources.
{"title":"Machining of TiAl6V4 Using Lubricants Containing Renewable Microalgae-Born Performance Additives","authors":"Thomas Koch, Dominik Wenzel, Ralf Gläbe","doi":"10.2478/ama-2024-0007","DOIUrl":"https://doi.org/10.2478/ama-2024-0007","url":null,"abstract":"Abstract Titanium and its alloys represent a special class of materials. A density of 4.81 g/cm3, a tensile strength of over 1,200 MPa, a fatigue strength greater than that of steel, a low modulus of elasticity and its self-passivating, inert surface make titanium an ideal material for lightweight structures in aerospace, marine applications, the chemical industry and medical implants. Although titanium is inert in its oxidised state, its nascent surface created in machining reacts with almost everything in its environment, including the tool. Moreover, its poor thermal conductivity results in high thermal stress on the tools. Overall, these properties lead to high wear rates and result in the requirement for finding a particularised solution for processes such as milling that involve the need to overcome such challenges. Such processes therefore require lubricants with well-selected performance additives. However, most of these performance additives are based on mineral oil and thus come from a non-renewable resource. In the presented work, environmental-friendly alternatives to conventional mineral oil-based performance additives were investigated. Due to the working mechanisms of performance additives in machining, this work focusses on sulphur- and phosphorus-containing polysaccharides and proteins from microalgae. It has been successfully shown that lubricants using extracts from microalgae as performance additives can be used for high-speed milling (HSC) of TiAl6V4. The investigated extracts were able to reach the performance level of conventional additives in terms of tool lifetime and wear. The results obtained show that appropriate alternatives to mineral oil-based additives exist from renewable raw-material sources.","PeriodicalId":44942,"journal":{"name":"Acta Mechanica et Automatica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139381359","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}
Abstract The primary objective of this research is to extend the concept of fractionalized Casson fluid flow. In this study, a comprehensive analysis of magnetohydrodynamic (MHD) natural convective flow of Casson fluid is conducted, focusing on obtaining analytical solutions using the non-integer-order derivative known as the Yang–Abdel-Aty–Cattani (YAC) operator. The YAC operator utilized in this research possesses a more generalized exponential kernel. The fluid flow is examined in the vicinity of an infinitely vertical plate with a characteristic velocity denoted as u0. The mathematical modelling of the problem incorporates partial differential equations, incorporating Newtonian heating and ramped conditions. To facilitate the analysis, a suitable set of variables is introduced to transform the governing equations into a dimensionless form. The Laplace transform (LT) is then applied to the fractional system of equations, and the obtained results are presented in series form and also expressed in terms of special functions. The study further investigates the influence of relevant parameters, such as α, β, Pr, Q, Gr, M, Nr and K, on the fluid flow to reveal interesting findings. A comparison of different approaches reveals that the YAC method yields superior results compared to existing operators found in the literature. Graphs are generated to illustrate the outcomes effectively. Additionally, the research explores the limiting cases of the Casson and viscous fluid models to derive the classical form from the YAC fractionalized Casson fluid model.
{"title":"A Fractional Study of MHD Casson Fluid Motion With Thermal Radiative Flux and Heat Injection/Suction Mechanism Under Ramped Wall Condition: Application of Rabotnov Exponential Kernel","authors":"Aziz Ur Rehman, F. Jarad, M. B. Riaz","doi":"10.2478/ama-2024-0011","DOIUrl":"https://doi.org/10.2478/ama-2024-0011","url":null,"abstract":"Abstract The primary objective of this research is to extend the concept of fractionalized Casson fluid flow. In this study, a comprehensive analysis of magnetohydrodynamic (MHD) natural convective flow of Casson fluid is conducted, focusing on obtaining analytical solutions using the non-integer-order derivative known as the Yang–Abdel-Aty–Cattani (YAC) operator. The YAC operator utilized in this research possesses a more generalized exponential kernel. The fluid flow is examined in the vicinity of an infinitely vertical plate with a characteristic velocity denoted as u0. The mathematical modelling of the problem incorporates partial differential equations, incorporating Newtonian heating and ramped conditions. To facilitate the analysis, a suitable set of variables is introduced to transform the governing equations into a dimensionless form. The Laplace transform (LT) is then applied to the fractional system of equations, and the obtained results are presented in series form and also expressed in terms of special functions. The study further investigates the influence of relevant parameters, such as α, β, Pr, Q, Gr, M, Nr and K, on the fluid flow to reveal interesting findings. A comparison of different approaches reveals that the YAC method yields superior results compared to existing operators found in the literature. Graphs are generated to illustrate the outcomes effectively. Additionally, the research explores the limiting cases of the Casson and viscous fluid models to derive the classical form from the YAC fractionalized Casson fluid model.","PeriodicalId":44942,"journal":{"name":"Acta Mechanica et Automatica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139384091","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}
Abstract This article aims to implement the fuzzy control for an asynchronous motor after a general representation of the vector control. We develop MAMDANI type fuzzy algorithm for MAS speed regulation; it’s one purpose is to cancel static error, decrease overshoot, decrease response time, and rise time to obtain an adequate response of the process and regulation and to have a precise, fast, stable and robust system. This paper investigates the design of a fuzzy-based approach for monitoring the inversion of the rotational speed of an induction motor. We will indeed present a robust vector control technique ex-tended to blur in the event of a fault. Direct torque control is known to produce fast and robust response in the AC drive system. However, in a steady state, a rapid and unexpected change in speed can occur which could be dangerous. The performance of the conventional PID controller can be improved by implementing fuzzy logic techniques. The first step is the modelling of the whole system, including the capacitors, the induction generator and the loads. The model is obtained using the Park transformation. The results are thus compared with those of the standard PID control. This approach is applied to a three-phase asynchronous motor (LS90Lz). The presented study improves the transient response time and the precision of the servo system. An inversion of the reference speed of rotation is considered, and the results are very convincing.
{"title":"Fuzzy Based Supervision Approach in the Event of Rotational Speed Inversion in an Induction Motor","authors":"Noura Rezika Hatem Bellahsene","doi":"10.2478/ama-2024-0009","DOIUrl":"https://doi.org/10.2478/ama-2024-0009","url":null,"abstract":"Abstract This article aims to implement the fuzzy control for an asynchronous motor after a general representation of the vector control. We develop MAMDANI type fuzzy algorithm for MAS speed regulation; it’s one purpose is to cancel static error, decrease overshoot, decrease response time, and rise time to obtain an adequate response of the process and regulation and to have a precise, fast, stable and robust system. This paper investigates the design of a fuzzy-based approach for monitoring the inversion of the rotational speed of an induction motor. We will indeed present a robust vector control technique ex-tended to blur in the event of a fault. Direct torque control is known to produce fast and robust response in the AC drive system. However, in a steady state, a rapid and unexpected change in speed can occur which could be dangerous. The performance of the conventional PID controller can be improved by implementing fuzzy logic techniques. The first step is the modelling of the whole system, including the capacitors, the induction generator and the loads. The model is obtained using the Park transformation. The results are thus compared with those of the standard PID control. This approach is applied to a three-phase asynchronous motor (LS90Lz). The presented study improves the transient response time and the precision of the servo system. An inversion of the reference speed of rotation is considered, and the results are very convincing.","PeriodicalId":44942,"journal":{"name":"Acta Mechanica et Automatica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139381794","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}
Abstract The study addresses the topic of different fractional orders in the context of simulation as well as experiments using real electrical elements of fractional-order circuit. In studying the two solutions of the resistance-capacitance (RC) ladder circuit of appropriate parameters, different fractional orders of the electrical circuit are considered. Two fractional-order (non-integer) elements were designed based on the Continued Fraction Expansion (CFE) approximation method. The CFE method itself was modified to allow free choice of centre pulsation. It was also proposed that when making individual ladder circuits, in the absence of elements with the parameters specified by the program, they should be obtained by connecting commercially available elements in series or parallel. Finally, the theoretical analysis of such a circuit is presented using state-space method and verified experimentally.
{"title":"Analysis of Fractional Electrical Circuit Containing Two RC Ladder Elements of Different Fractional Orders","authors":"Ewa Piotrowska, Rafał Melnik","doi":"10.2478/ama-2024-0010","DOIUrl":"https://doi.org/10.2478/ama-2024-0010","url":null,"abstract":"Abstract The study addresses the topic of different fractional orders in the context of simulation as well as experiments using real electrical elements of fractional-order circuit. In studying the two solutions of the resistance-capacitance (RC) ladder circuit of appropriate parameters, different fractional orders of the electrical circuit are considered. Two fractional-order (non-integer) elements were designed based on the Continued Fraction Expansion (CFE) approximation method. The CFE method itself was modified to allow free choice of centre pulsation. It was also proposed that when making individual ladder circuits, in the absence of elements with the parameters specified by the program, they should be obtained by connecting commercially available elements in series or parallel. Finally, the theoretical analysis of such a circuit is presented using state-space method and verified experimentally.","PeriodicalId":44942,"journal":{"name":"Acta Mechanica et Automatica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139384008","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}
Abstract The work focuses on the dynamic stability problem of a simply supported three-layer beam subjected to a pulsating axial force. Two analytical models of this beam are developed: one model takes into account the non-linear hypothesis of cross-section deformation, and the other takes into account the standard “broken line” hypothesis. Displacements, strains and stresses for each model are formulated in detail. Based on the Hamilton principle, equations of motion are determined for each of these models. These systems of two differential equations for each model are approximately solved with the consideration of the axial pulsating force, and the fundamental natural frequencies, critical forces and the Mathieu equation are determined. Detailed studies are performed for an exemplary family of beams. The stable and unstable regions are calculated for the three pulsating load cases. The values of fundamental natural frequencies and critical forces of exemplary beams calculated from two models are compared.
{"title":"Dynamic Stability of a Three-Layer Beam – Generalisation of the Sandwich Structure Theory","authors":"K. Magnucki, E. Magnucka-Blandzi","doi":"10.2478/ama-2024-0001","DOIUrl":"https://doi.org/10.2478/ama-2024-0001","url":null,"abstract":"Abstract The work focuses on the dynamic stability problem of a simply supported three-layer beam subjected to a pulsating axial force. Two analytical models of this beam are developed: one model takes into account the non-linear hypothesis of cross-section deformation, and the other takes into account the standard “broken line” hypothesis. Displacements, strains and stresses for each model are formulated in detail. Based on the Hamilton principle, equations of motion are determined for each of these models. These systems of two differential equations for each model are approximately solved with the consideration of the axial pulsating force, and the fundamental natural frequencies, critical forces and the Mathieu equation are determined. Detailed studies are performed for an exemplary family of beams. The stable and unstable regions are calculated for the three pulsating load cases. The values of fundamental natural frequencies and critical forces of exemplary beams calculated from two models are compared.","PeriodicalId":44942,"journal":{"name":"Acta Mechanica et Automatica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139138697","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}