Mariya Konsulova-Bakalova - Academia.edu (original) (raw)
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Papers by Mariya Konsulova-Bakalova
Abstract In the present chapter, the basic characteristics of some types of burnishing processes ... more Abstract In the present chapter, the basic characteristics of some types of burnishing processes are considered in terms to obtain both smooth surfaces and also so-called “regular reliefs” onto different workpieces surfaces with different shape, including cylindrical, tapered, planar, and nonplanar (i.e., complex) surfaces. Some contemporary ball burnishing schemes for forming regular reliefs using computer-numerical-control (CNC) turn milling, milling, and multiaxis centers are presented, as well as their advantages and disadvantages in comparison with classical vibratory ball burnishing processes and vibro-tools working with manually operated metal cutting machines. The corresponding mathematical equations for obtaining the needed complex toolpath with optimal length according to burnished surface boundaries are given. The essential requirements on the CAD-CAM software also are described, as well as an overall algorithm for suitable numerical control programs generation using CAM is also given. The main regime parameters of ball burnishing processes and their influence on surface layer characteristics and regular relief’s cells are presented. The chapter finishes with some general conclusions and recommendations about the ball burnishing process implementation for forming regular reliefs using CNC machines as alternative of other burnishing processes.
MATEC web of conferences, 2019
In recent years, topology optimization methods are becoming more widely used in many engineering ... more In recent years, topology optimization methods are becoming more widely used in many engineering fields, and they are already being successfully integrated at the design stage of the different types of products. An active field of research in this area is the definition of appropriate constraints in topology optimization models in order to facilitate the production of the optimized objects. An algorithm for topology optimization of housing elements from gear reducers by using the capabilities of CAD-CAE topology optimization software is presented in the current work. The purposed algorithm is taking into account the resulting loads during operation of the reducer, the geometrical and manufacturing constraints of the production process of these housing elements. Obtained results from conducted Taguchi experimental study to investigate the impact of some topology optimization control parameters over optimized 3D-model also are shown and discussed. Conclusions on the applicability of the algorithm have been made. 2 Specifics of the TO application for certain types of 3D CAD-CAE models Since its creation (lately 80's) until now, dozens of variations of TO methods have been developed and now many of them are integrated into most widespread
Sustainable Development and Innovations in Marine Technologies, 2019
International Polymer Science and Technology, 2003
Translation submitted by P. Curtis Epoxy-phenol composites (EPCs) are widely used in different se... more Translation submitted by P. Curtis Epoxy-phenol composites (EPCs) are widely used in different sectors of industry (in particular, for the protective inner lining of food cans) owing to the comparative cheapness and availability of the feedstock and to their combination of high protective characteristics (good chemical resistance in various media, excellent adhesion strength, etc.) and also good physicomechanical properties.
Polymer-Plastics Technology and Engineering, 2006
Machines. Technologies. Materials., 2019
The measurement of deviations from planeness, rectilinearity and parallelism of plane surfaces is... more The measurement of deviations from planeness, rectilinearity and parallelism of plane surfaces is a set of measuring tools (instruments, devices, high performance measuring means, etc.) and the conditions under which the measurements are made (temperature mode, way of basing during the measurment, stability or non-stability of the measured quantity in the measurement process, etc.), which implies that the method of measurement is a complex concept, i.e. a set of signs and conditions that accompany the measurement process. The present work determines the surface quality obtained after air plasma cutting of 41Cr4 steel by standard methodologies for measuring its parameters. For this purpose, a methodology is used to measure the shape and configuration as well as a methodology for measuring the profile of the surface.
Materials
The present work focusses on the research of the plastic deformation accumulated effect obtained ... more The present work focusses on the research of the plastic deformation accumulated effect obtained after two different plastic deformation treatments, over the fatigue life of AISI 304 austenitic stainless steel. The research is focused on ball burnishing as a finishing process to form specific, so-called “regular micro-reliefs” (RMRs) on a pre-rolled stainless-steel sheet. RMRs are formed using a CNC (Computerized Numerically Controlled) milling machine and toolpaths with the shortest unfolded length, generated by an improved algorithm, based on the Euclidean Distance calculation. The effect of the predominant tool trajectory direction during the ball burnishing process (which can be coinciding or transverse with the rolling direction), the magnitude of applied deforming force, and feed-rate is subjected to evaluation using Bayesian rule analyses of experimentally obtained results for the fatigue life of AISI 304 steel. The obtained results give us reason to conclude that the fatigue...
Journal of microbiology, biotechnology and food sciences
Sludge from a purification plant for waste waters are studied for presence of pathogenic and non-... more Sludge from a purification plant for waste waters are studied for presence of pathogenic and non-pathogenic microflora. Their disinfection is carried out by applying lime treatment (10%, 20%, 30% lime) with two species vegetation – lavender (Lavandula) and basil (Ocimum). The results obtained after the processing of the sludge about the quantity microflora in them are studied for presence of a correlation connection between the concentration of the lime solution and the quantity of microorganisms. The obtained results show a strong correlation connection among the studied quantities. This gives grounds to be looked for a mathematical model on description of the microflora quantity in the sludge. More factors are added for the purpose – temperature, humidity and pH. In the article are presented the regression equations for the different methods of disinfection. The results give grounds to be affirmed that most of them can be used successfully for finding the quantity microflora in st...
2021 International Conference on Biomedical Innovations and Applications (BIA)
This article presents an example of applying SolidWorks in the training in mechanical engineering... more This article presents an example of applying SolidWorks in the training in mechanical engineering. The main features of the design of the parts intended for injection molding are mentioned. SolidWorks allows all these recommendations to be implemented when creating the details. The text explains the simulation settings that are made in SolidWorks Plastics when simulating injection molding. Through a specific example, it is referred to how making an analysis of the results obtained.
Materials
The present work describes an experimental investigation of the fatigue durability of AISI 304 an... more The present work describes an experimental investigation of the fatigue durability of AISI 304 and AISI 316L austenitic stainless steels, which have regular reliefs (RR) of the IV-th type, formed by ball burnishing (BB) on flat surfaces, using a computer numerical control (CNC) milling center. The methodology and the equipment used for obtaining regular reliefs, along with a vibration-induced fatigue test setup, are presented and described. The results from the BB process and the fatigue life experiments of the tested austenitic stainless steels are gathered, using the approach of factorial design experiments. It was found that the presence of RR of the IV-th type do not worsen the fatigue strength of the studied steels. The Pareto, t-test and Bayesian rule techniques are used to determine the main effects and the interactions of significance between ball burnishing regime parameters. A stochastic model is derived and is used to find when the probability of obtaining the maximum fat...
ANNUAL JOURNAL OF TECHNICAL UNIVERSITY OF VARNA, BULGARIA
In the description of complex objects, we need methods which could reflect the complex interconn... more In the description of complex objects, we need methods which could reflect the complex interconnections between components and sift out if possible those of them which are substantial for the specific application. It is offered in this publication the pattern recognition methods should be used as a unified method for processing of data from complex objects. The proposed algorithm may be used in the recognition of the condition of objects of various nature. The indicated examples prove the practical applicability of the methodology as they represent the solution of specific practical problems.
Machines
This paper presents the results of a conducted topology management optimization study based on th... more This paper presents the results of a conducted topology management optimization study based on the finite element analysis on a two-stage spur gear reducer housing body and cover using the SOLIDWORKS Simulation module. The main goal of the study is to optimize the overall weight of the reducer by thinning specific areas of the casted gearbox housing elements according to the calculated minimal strain energy. The topology optimization algorithm that is used in current research gives an optimal structural shape of the housing elements of the reducer with the largest stiffness, considering the given amount of mass that will be removed from the initial design space. The complete sequence of steps for conducting the topology management optimization study is shown, taking into account the constraints arising from the construction features and the method of manufacturing the housing elements of the gear reducer. Conclusions on the use of the topology optimization results are given and pote...
Abstract In the present chapter, the basic characteristics of some types of burnishing processes ... more Abstract In the present chapter, the basic characteristics of some types of burnishing processes are considered in terms to obtain both smooth surfaces and also so-called “regular reliefs” onto different workpieces surfaces with different shape, including cylindrical, tapered, planar, and nonplanar (i.e., complex) surfaces. Some contemporary ball burnishing schemes for forming regular reliefs using computer-numerical-control (CNC) turn milling, milling, and multiaxis centers are presented, as well as their advantages and disadvantages in comparison with classical vibratory ball burnishing processes and vibro-tools working with manually operated metal cutting machines. The corresponding mathematical equations for obtaining the needed complex toolpath with optimal length according to burnished surface boundaries are given. The essential requirements on the CAD-CAM software also are described, as well as an overall algorithm for suitable numerical control programs generation using CAM is also given. The main regime parameters of ball burnishing processes and their influence on surface layer characteristics and regular relief’s cells are presented. The chapter finishes with some general conclusions and recommendations about the ball burnishing process implementation for forming regular reliefs using CNC machines as alternative of other burnishing processes.
MATEC web of conferences, 2019
In recent years, topology optimization methods are becoming more widely used in many engineering ... more In recent years, topology optimization methods are becoming more widely used in many engineering fields, and they are already being successfully integrated at the design stage of the different types of products. An active field of research in this area is the definition of appropriate constraints in topology optimization models in order to facilitate the production of the optimized objects. An algorithm for topology optimization of housing elements from gear reducers by using the capabilities of CAD-CAE topology optimization software is presented in the current work. The purposed algorithm is taking into account the resulting loads during operation of the reducer, the geometrical and manufacturing constraints of the production process of these housing elements. Obtained results from conducted Taguchi experimental study to investigate the impact of some topology optimization control parameters over optimized 3D-model also are shown and discussed. Conclusions on the applicability of the algorithm have been made. 2 Specifics of the TO application for certain types of 3D CAD-CAE models Since its creation (lately 80's) until now, dozens of variations of TO methods have been developed and now many of them are integrated into most widespread
Sustainable Development and Innovations in Marine Technologies, 2019
International Polymer Science and Technology, 2003
Translation submitted by P. Curtis Epoxy-phenol composites (EPCs) are widely used in different se... more Translation submitted by P. Curtis Epoxy-phenol composites (EPCs) are widely used in different sectors of industry (in particular, for the protective inner lining of food cans) owing to the comparative cheapness and availability of the feedstock and to their combination of high protective characteristics (good chemical resistance in various media, excellent adhesion strength, etc.) and also good physicomechanical properties.
Polymer-Plastics Technology and Engineering, 2006
Machines. Technologies. Materials., 2019
The measurement of deviations from planeness, rectilinearity and parallelism of plane surfaces is... more The measurement of deviations from planeness, rectilinearity and parallelism of plane surfaces is a set of measuring tools (instruments, devices, high performance measuring means, etc.) and the conditions under which the measurements are made (temperature mode, way of basing during the measurment, stability or non-stability of the measured quantity in the measurement process, etc.), which implies that the method of measurement is a complex concept, i.e. a set of signs and conditions that accompany the measurement process. The present work determines the surface quality obtained after air plasma cutting of 41Cr4 steel by standard methodologies for measuring its parameters. For this purpose, a methodology is used to measure the shape and configuration as well as a methodology for measuring the profile of the surface.
Materials
The present work focusses on the research of the plastic deformation accumulated effect obtained ... more The present work focusses on the research of the plastic deformation accumulated effect obtained after two different plastic deformation treatments, over the fatigue life of AISI 304 austenitic stainless steel. The research is focused on ball burnishing as a finishing process to form specific, so-called “regular micro-reliefs” (RMRs) on a pre-rolled stainless-steel sheet. RMRs are formed using a CNC (Computerized Numerically Controlled) milling machine and toolpaths with the shortest unfolded length, generated by an improved algorithm, based on the Euclidean Distance calculation. The effect of the predominant tool trajectory direction during the ball burnishing process (which can be coinciding or transverse with the rolling direction), the magnitude of applied deforming force, and feed-rate is subjected to evaluation using Bayesian rule analyses of experimentally obtained results for the fatigue life of AISI 304 steel. The obtained results give us reason to conclude that the fatigue...
Journal of microbiology, biotechnology and food sciences
Sludge from a purification plant for waste waters are studied for presence of pathogenic and non-... more Sludge from a purification plant for waste waters are studied for presence of pathogenic and non-pathogenic microflora. Their disinfection is carried out by applying lime treatment (10%, 20%, 30% lime) with two species vegetation – lavender (Lavandula) and basil (Ocimum). The results obtained after the processing of the sludge about the quantity microflora in them are studied for presence of a correlation connection between the concentration of the lime solution and the quantity of microorganisms. The obtained results show a strong correlation connection among the studied quantities. This gives grounds to be looked for a mathematical model on description of the microflora quantity in the sludge. More factors are added for the purpose – temperature, humidity and pH. In the article are presented the regression equations for the different methods of disinfection. The results give grounds to be affirmed that most of them can be used successfully for finding the quantity microflora in st...
2021 International Conference on Biomedical Innovations and Applications (BIA)
This article presents an example of applying SolidWorks in the training in mechanical engineering... more This article presents an example of applying SolidWorks in the training in mechanical engineering. The main features of the design of the parts intended for injection molding are mentioned. SolidWorks allows all these recommendations to be implemented when creating the details. The text explains the simulation settings that are made in SolidWorks Plastics when simulating injection molding. Through a specific example, it is referred to how making an analysis of the results obtained.
Materials
The present work describes an experimental investigation of the fatigue durability of AISI 304 an... more The present work describes an experimental investigation of the fatigue durability of AISI 304 and AISI 316L austenitic stainless steels, which have regular reliefs (RR) of the IV-th type, formed by ball burnishing (BB) on flat surfaces, using a computer numerical control (CNC) milling center. The methodology and the equipment used for obtaining regular reliefs, along with a vibration-induced fatigue test setup, are presented and described. The results from the BB process and the fatigue life experiments of the tested austenitic stainless steels are gathered, using the approach of factorial design experiments. It was found that the presence of RR of the IV-th type do not worsen the fatigue strength of the studied steels. The Pareto, t-test and Bayesian rule techniques are used to determine the main effects and the interactions of significance between ball burnishing regime parameters. A stochastic model is derived and is used to find when the probability of obtaining the maximum fat...
ANNUAL JOURNAL OF TECHNICAL UNIVERSITY OF VARNA, BULGARIA
In the description of complex objects, we need methods which could reflect the complex interconn... more In the description of complex objects, we need methods which could reflect the complex interconnections between components and sift out if possible those of them which are substantial for the specific application. It is offered in this publication the pattern recognition methods should be used as a unified method for processing of data from complex objects. The proposed algorithm may be used in the recognition of the condition of objects of various nature. The indicated examples prove the practical applicability of the methodology as they represent the solution of specific practical problems.
Machines
This paper presents the results of a conducted topology management optimization study based on th... more This paper presents the results of a conducted topology management optimization study based on the finite element analysis on a two-stage spur gear reducer housing body and cover using the SOLIDWORKS Simulation module. The main goal of the study is to optimize the overall weight of the reducer by thinning specific areas of the casted gearbox housing elements according to the calculated minimal strain energy. The topology optimization algorithm that is used in current research gives an optimal structural shape of the housing elements of the reducer with the largest stiffness, considering the given amount of mass that will be removed from the initial design space. The complete sequence of steps for conducting the topology management optimization study is shown, taking into account the constraints arising from the construction features and the method of manufacturing the housing elements of the gear reducer. Conclusions on the use of the topology optimization results are given and pote...