CAE Systems Research Articles

THE TECHNIQUE OF REVERSE ENGINEERING OF ELECTROMAGNETIC CONTACTOR

When creating new objects, reverse engineering technologies are often used. Unlike traditional (direct) engineering, when a product is created from scratch, with reverse engineering, a new product is developed based on a prototype, which significantly saves money and reduces time. The purpose of the study is to systematize and evaluate the main approaches of reverse engineering of modern electromagnetic contactors. Materials and methods. The paper uses comparative analysis and generalization of the results in graphical form, and computer mathematical modeling in the COMSOL software product. Research results. A variant of the content and sequence of stages which is typical of reverse engineering of an electromagnetic contactor is presented. The stages of reverse engineering of an electromagnetic contactor are formulated and analyzed in detail. The main part of the design consists in the development of a 3D model of the prototype based on the results of digitization of its parts, as well as modeling and research of the main components (contact and magnetic systems) using their computer mathematical models (model experiments). As an example, the modeling of the magnetic system of a DC contactor is considered in detail. Based on the results of optimization and design development, a 3D model of the new contactor is developed. Conclusions. A method of reverse engineering of an electromagnetic contactor based on the use of modern CAD and CAE systems is proposed. The main difference of the technique is the optimization of the design based on the results of model experiments performed with minimal time in standard software products that do not require expertise.

Increasing the efficiency of design in CAD CAE systems based on the application of parametrization methods

Modern global trends in green energy indicate a constant increase in the share of energy obtained by burning woody biomass. The volumes of timber harvesting and processing are growing steadily. The Russian Federation is no exception, where logging and wood processing play an important role in economic, social, and environmental terms. Technological operations related to wood processing are predominantly mechanized. Most often, the machinery and equipment used in enterprises are imported. The use of imported products entails a number of consequences related to the dynamics of geopolitical development. It is necessary to minimize the dependence of enterprises on foreign equipment. There is a need to develop and modernize domestic logging machinery and equipment. To ensure the production of high-quality and competitive machines, it is necessary to resort to a set of activities related to design. Ensuring the necessary performance characteristics when developing a project requires financial and time costs, since it is necessary to resort to full-scale prototyping. Minimizing financial costs during design is the most important task of specialists, since the saved resources will allow the enterprise to open up new paths for development.

Experimental Research Regarding the Defects Occurring at the Injection-molding of Long Technical Parts, Made of Thermoplastic Material, Using CAE Systems. Case Study

In this paper, the authors propose to carry out a case study, on a visual part made of thermoplastic material from the automotive industry. Using the most up-to-date CAE systems, we will try to highlight the main appearance problems in long parts, namely the appearance of weld lines at the meeting of the flow fronts. The part will be processed using sequential, as well as non-sequential injection systems, respectively, in order to highlight the difference between the two, respectively to compare these two tests with the results of rheological simulation (CAE).

Підхід до чисельного моделювання просторових рухів газорідинного сере-довища в паливному баку космічного ступеня в умовах мікрогравітації з урахуванням гарячої зони

Space propulsion systems ensure multiple startups and shutdowns of the main liquid-propellant rocket engines in microgravity conditions for spacecraft preset motions and reorientation control. During the passive flight of a space stage (after its main engine shutdown), the liquid propellant in the tanks continues moving by inertia in microgravity and moves as far away from the propellant management device as possible. In this case, the pressurization gas is displaced to the propellant management device, which creates the potential danger of the gas entering the engine inlet in quantities unacceptable for multiple reliable engine restarts. In this regard, the determination of the parameters of fluid movement in propellant tanks under microgravity conditions is a pertinent problem to be solved in the designing of liquid-propellant propulsion systems. This paper presents an approach to the theoretical calculation of the parameters of motion of the gas–liquid system in the propellant tanks of today’s space stages in microgravity conditions. The approach is based on the use of the finite element method, the Volume of Fluid method, and up-to-date computer tools for finite-element analysis (Computer Aided Engineering - CAE systems). A mathematical simulation of the spatial motion of the liquid propellant and the formation of free gas inclusions in passive flight was performed, and the motion parameters and shape of the free liquid surface in the tank and the location of gas inclusions were determined. The liquid motion in a model spherical tank in microgravity conditions was simulated numerically with and without account for the hot zone near the tank head. The motion parameters of the gas-liquid interface in a model cylindrical tank found using the proposed approach are in satisfactory agreement with experimental data. The proposed approach will significantly reduce the extent of experimental testing of space stages under development.

Розробка системи кріплення мікрохвильового радара для виявлення перешкод

The subject of scientific research is the consideration of layout options and the possibility of placing a microwave radar on board a helicopter. The goal is to develop a methodology for creating a three-dimensional parametric model of the radar mounting system. The task is to develop an algorithm (sequence of steps) for creating a three-dimensional parametric radar mount model without making changes to the basic design and layout of an existing aircraft. The methods used are: methods of analytical geometry; methods of scanning three-dimensional objects; methods of three-dimensional parametric modeling using modern computer-integrated CAD\CAM\CAE systems in the context of existing assemblies. The following results were obtained. On the basis of the scanned point cloud, a parametric model of the nose of the aircraft was created, the area of additional equipment installed on the aircraft was determined, a microwave radar mounting system was developed, a three-dimensional model of the mounting system was made, and design documentation was developed for it. Conclusions. The scientific novelty of the obtained results is as follows: a general algorithm, stages of design and three-dimensional parametric modeling of the aircraft unit using the methods and principles of reverse engineering have been developed. The implementation of this algorithm, methods and principles of reverse engineering is presented on en example of the creation of a microwave radar mounting system on the F1 compartment of the Mi8-MSB1 helicopter. The work presents the stages of designing a platform for attaching a microwave obstacle detection radar to the frame of the F1 compartment Mi-8MSB1 helicopter, as well as the radar scanning zone during the flight.

The approach to numerical simulation of the spatial movement of fluid with forming free gas inclusions in propellant tank at space flight conditions

The space propulsion systems ensure se veral start-ups and shutdowns of main liquid-propellant rocket engines under microgravity conditions for the spacecraft program movements and reorientation control. During the passive flight of the space stage (after its main engine shutdown), the liquid propellant in the tanks continues to move by inertia in microgravity away from the propellant management device as much as possible. In this case, the pressurization gas is displaced to the propellant management device, which creates the potential danger of gas entering the engine inlet in quantities unacceptable for the reliable engine restart. In this regard, determining the parameters of fluid movement in propellant tanks in microgravity conditions is an urgent problem that needs to be solved in the design period of liquid propulsion systems. We have developed an approach to the theoretical computation of the parameters of the motion of the ‘gas — fluid’ system in the propellant tanks of modern space stages in microgravity conditions. The approach is based on the use of the finite element method, the Volume of Fluid method and modern computer tools for finite-element analysis (Computer Aided Engineering — CAE systems). For the passive leg of the launch vehicle space flight, we performed mathematical modeling of the spatial movement of liquid propellant and forming free gas inclusions and determined the parameters of movement and shape of the free surface of the liquid in the tank as well as the location of gas inclusions. The numerical simulation of the fluid movement in an experimental sample of a spherical shape tank was performed with regard to the movement conditions in the SE Yuzhnoye Design Bureau ‘Drop tower’ for studying space object s in microgravity. The motion parameters of the ‘gas — fluid’ interface obtained as a result of mathematical modeling are in satisfactory agreement with the experimental data obtained. The use of the developed approach will significantly reduce the amount of experimental testing of the designed space stages.

PROJECT CONCEPTION OF CAE-SYSTEM FOR WEAR ANALYSIS OF FRICTION BEARING UNDER CONDITIONS OF SHAFT AND LINER AXIS MISALIGNMENT

Modelling of wear processes is an important stage in the design of mechanisms. Such virtual studies allow predicting the service life of components and the machine as a whole. Modern algorithms of CAE-systems allow performing such analysis with high accuracy and taking into account not only material and operating conditions of the mechanism, but also errors that occurred during the manufacturing and assembly of a particular part. These parts require high requirements to the accuracy of manufacturing and assembly, but within the tolerances of the fields errors of mutual positioning are still allowed, which in turn can significantly affect the service life of the mechanism. Therefore, the task of modeling the wear process of the shaft and sleeve in conditions of mutual misalignment of the axes is relevant. Such sliding pairs exist in almost all machines, including car engines, power generation turbines, etc. In this article it is offered to use the module-integrated approach for modeling of wear processes in tribotechnics, providing use of CAE-systems for definition of functioning conditions of friction units as a system core, and construction of separate modules which in this or that degree are integrated into existing CAE systems. to define values of wear of elements of friction pairs that allows to consider mutual influence of wear and change of functioning conditions in the course of operation. The practical implementation of the module-integrated approach is shown by the example of solving the problem of radial plain bearings wear during the misalignment of the shaft and bush axes in the ANSYS environment. The module of representation of multidimensional matrixes of static or dynamic data, providing essential increase in speed of data processing and quality level of the further analysis of the visualized information from any subject area, is developed.

Підхід до аналізу поздовжньої стійкості рідинної ракети-носія пакетної схеми компонування

The “core and strap-on boosters” layout of launch vehicle (LV) stages is quite common in heavy LV development. However, POGO oscillations in liquid-propellant LVs with this stage layout have some features. It is shown that the structure of LVs of this type as a dynamic object has a dense spectrum of natural frequencies and complex spatial mode shapes. The longitudinal oscillations of the identical elements of the LV side strap-on boosters may be in phase or in antiphase, while the longitudinal mode shapes of the LV central core and strap-on boosters may differ both in phase and in amplitude. In flight, the thrust of the engines of the side strap-on boosters may also oscillate in phase or in antiphase, as a result of which the interaction of the LV structure with the sustainer propulsion systems of the side strap-on boosters may have both a stabilizing and a destabilizing effect on the POGO stability of a liquid-propellant LV. This paper presents a mathematical model of the “liquid-propellant propulsion systems – LV structure” dynamic system. The model describes the interaction of the longitudinal vibrations of the structure of a two-stage “core and strap-on boosters” LV with the core and strap-on booster propulsion systems. The free longitudinal vibrations of the structure of a ‘core and strap-on boosters’ LV were simulated using computer-aided finite element design tools (CAE systems). The simulation was the first to account for the dissipation of the liquid propellant and LV structure oscillation energy. The paper suggests an approach to analyzing the POGO stability of liquid-propellant “core and strap-on boosters” LVs with the use of the Nyquist criterion generalized to the case of multidimensional dynamic systems. The approach is based on opening the thrust feedback loops of the “liquid-propellant propulsion systems – structure” closed-loop dynamic system and studying the stability of the one-channel systems obtained in this way. Based on the proposed approach, the interaction between the longitudinal vibrations of the “core and strap-on boosters” LV structure and low-frequency processes in the liquid-propellant sustainer propulsion systems of the LV first stage was studied numerically.

MODELING OF TECHNOLOGICAL PROCESS OF SOWING GRAIN CROPS BY OPENERS FOR DIRECT SOWING ON SLOPE

To date, sowing is one of the most urgent tasks, therefore, universal sowing equipment is widely in demand, which should ensure a uniform distribution of the number of plants per unit area to create the same conditions for development. Theoretical studies were carried out using the methods of theoretical mechanics, strength of materials, probability theory, mathematical analysis and modeling. Research is carried out on the basis of numerous implementations of the equations of continuum dynamics in applied engineering calculation programs - CAE systems. The article provides a theoretical analysis of the interaction of the soil layer with the surface of the working body of the seeder for the implementation of the technological process of sowing seeds of grain crops on the slopes. We have obtained a diagram of the forces acting on the soil during the working process, a diagram of the forces acting on the soil layer while moving along the slope, a diagram for determining the parameters of the working plane, initial and limiting conditions for the interaction of the working body with the soil environment, a diagram for determining the speed of the soil layer, a diagram changes in the speed of the soil layer on the slopes, the scheme of forces acting on the soil layer on the slopes, the dependence of the gravity force of the soil layer on the surface of the working body and the backing force on the angle of the slope, the dependence of the backing force on the angle. The initial and limiting conditions of the mathematical model of the technological process are considered, and a technique for implementing the mathematical model of the technological process of the work of the working body on slopes with different values of the angle of inclination of the working surface is developed. A mathematical model of the technological process of tillage on different types of agricultural landscapes by experimental working bodies has been developed. The initial and limiting conditions of the mathematical model of the technological process of processing are established, taking into account the slope of the working surface of the field.

CAE studies of river ice cover aerodynamics

The paper provides an overview of autumn-winter movements and ice breaking on river shipping routes. The range of tasks of ensuring the safety of ice navigation is highlighted, which requires the predict of wind loads on hummocky ice fields of small floe fractions. As a complex argument for the characterization of such a field, the coefficient of its windage is proposed. The statistical function of the distribution of the height of the hummocks is revealed.
 To speed up the process of three-dimensional description of the geometry of the ice surface with a given law of the distribution of hummocks, the joint use of CAD and CAE systems is proposed. A series of CAE «purges» of model ice fields was carried out. The dependence of aerodynamic loads on the direction of atmospheric flow has been confirmed by the analysis of the results of CAE-modeling of wind impact on small floe ices. The conclusion is made about the limitations of the application of the classical equation of gas dynamics in relation to the studied ice.

The research on matrix of press-form stiffness and steadiness

The formalized algorithm of calculation of rectangular matrix of press-form is developed on durability and inflexibility with the purpose of determination of optimum geometrical sizes which would provide it optimum operating capacity. For this purpose CAD and CAE systems were used, in particular Solidwork, Matcad. А three-dimensional model of the mold matrix was designed. Research and analysis of the stress-strain state of the matrix was carried out and its optimal parameters were determined. As a result, it makes it possible to optimize the structure of the matrix in terms of stiffness and stability and ensure its optimal performance.

Application of computer systems for modeling dynamic processes of lifting machines

The main task of mechanical engineering is to organize the production of a range of machines to meet the needs of all industries. These are power, transport, lifting and transport units, agricultural machinery, construction industry, etc. Among them, one can single out devices in which the relative movement of their parts is assigned, that is, kinematic pairs are included in the calculation models. The real operating conditions of machines are varied, but most often they are associated with periodic starts-stops, which determines the relevance of the study of unsteady modes. The analysis of the operation of such models becomes more complicated. For successful design results, mathematical modeling of individual processes in mechanisms is carried out. One of the first calculations is dynamic. Modern, available CAD / CAE systems for modeling and analysis provide automation capabilities, building more realistic design models. The paper discusses the approbation of the use of CAD for modeling the dynamics of a jib crane with a set of four units: platform, boom, sleeve and rod. The developed model is combined: the platform and the sleeve correspond to the kinetostatic model, and the boom and rod are elastic. The crane is designed to perform lifting operations in a vertical plane, with the possibility of relative movement in 3 rotational and one translational kinematic pairs. The performed calculations of the static, modal and dynamic analyzes of the links of the mechanism confirm the adequacy of their models. Among them is the task of instantaneous load application, which is typical for the "lifting and picking" operating mode of crane lifting mechanisms. The deformation of the entire structure in one of the boom positions is also considered. The determination of the reaction forces in the hydraulic cylinder provides important information for the selection of the power unit.

Data transformation technology of 3D ship structure model for approval

Objectives Chinese ship design and approval institutions usually use different 3D design platforms, which can cause the problems of unsmooth model transfer and ineffective data conversion. This paper addresses the data conversion techniques of 3D ship structure models to ascertain whether a converted model can be directly used by classification societies for approval. Methods By analyzing the model data of the CAD and CAE systems, the required data for generating an approval-oriented 3D hull structure model is summarized. The storage format of the required data and the interface between the stored data and common 3D software platforms are introduced. Taking a cargo tank section of a ship as an example, the required data of the 3D model of the target section is stored in an XML data file. Based on this data file, the design model and FE analysis model of the target section are reconstructed through CATIA and Patran software, and equipped with a secondary developed interface. Results The reconstructed model has been submitted to Bureau Veritas (BV) for direct approval of the structural design. Conclusions The data conversion method proposed in this paper simplifies model transfer among different platforms, and can provide valuable references for realizing the paper-free approval of 3D ship models.

Industrial application of knowledge-based engineering in commercial CAD / CAE systems

KBE systems have been studied by researchers for about 30 years. Numerous papers have been published, approaches have been formally built and methodologies have been developed. Despite these achievements, attempts at a wider and more effective application of KBE in industry still encounter various difficulties, both in the process of creating KBE applications and in conducting their further development. The reasons for this state of affairs are both the rapidly evolving IT reality of modern industry and the need for KBE methods, tools and solutions to keep up with it.Nowadays, many directions in KBE development and improvement as well as their industrial implementation are possible. The authors have examined a number of them, analysed and evaluated the obtained results, and proposed sets of guidelines that can both improve the quality of applied KBE solutions and make their development processes more efficient.The study includes references to various information streams present in industry, various structures of this information, and their impact on the developed solutions. The influence of external conditions was also taken into account. The work also presents real, industrial examples of generating, developing and applying UML templates in knowledge modelling for the needs of KBE applications. The applied templates are the result of a synthetic reflection based on standard programming constructions used by teams of programmers in specific industrial conditions. The created templates are the effect of considering the very individualized specifics of software development, as well as the individualized process of the evolution of a specific project area.

СРАВНЕНИЕ ЭФФЕКТИВНОСТИ ИСПОЛЬЗОВАНИЯ ТЕХНОЛОГИЙ BIM И CAD С ПОМОЩЬЮ МАТЕМАТИЧЕСКОЙ МОДЕЛИ

the article reveals definitions and the entity of computer-aided design and building information modeling. The content and effect of using information modeling at various phase of the life cycle of a real estate object are described in the article. The level of BIM applying in Russia is analyzed, data is obtained that the majority of AEC organizations do not use information modeling. A comparative evaluation of the applying of various CAE systems using mathematical modeling in the MATLAB environment using the Fuzzy Logic Toolbox extension package is carried out. Based on the obtained results, we can make a conclusion about the effectiveness of using building information modeling. The information in this article is relevant for designers, real estate investors, and leaders of AEC organizations. The obtained evaluation of project technology is able to induce stakeholders to analyze alternative technology of project and estimate the expediency of Russian enterprise's transition to the use of BIM technology.

Архитектура цифровой платформы исследования и проектирования инноваций в машино- и приборостроении

Platform business models for research and design of innovative products have not found widespread use in the national mechanical engineering branch yet. Meanwhile, the manufacturing process organization based on digital twin prototype and competence distribution models is a world trend in the innovative product design and implementation. The applied digital platform implemented at the Innovation Design Center of the Industrial Technopark of the Republic of Mordovia provides requirements engineering, system architecture engineering and test engineering services. These services are carried out with the support of software systems and related equipment operating in a single information environment. One of the challenges of the digital platform architectural design is the choice of methods and tools for integrating CAD / CAM / CAE systems, industrial software, test and process equipment and newly developed services into the PLM Teamcenter environment. Another task is to provide access to platform resources for geographically remote clients with maximum localization of services production within the platform. The task is solved on the basis of a powerful instrumental core, which includes the most modern computing and telecommunication systems, technological, test equipment and measuring instruments. The structure of the digital platform deployment considered in the paper reflects its current status.

ТРАНСЛЯЦИЯ ГЕОМЕТРИЧЕСКИХ МОДЕЛЕЙ ОДНОКОНТУРНЫХ ГЕОДЕЗИЧЕСКИХ КУПОЛОВ ИЗ ARCHICAD В НЕЙТРАЛЬНЫЙ STEP ФОРМАТ

The methods of data exchange between CAD and CAE systems are described. The first method is using direct conversion, the second method is using neutral formats. The description of the modular system for designing and analysis the strength and stability of single-contour and double-contour geodesic shells GeoTran is given. The direct translation of geometric models from ArchiCAD to Patran/Nastran / Dytran has the disadvantage of having to develop translators for each data exchange scheme. It is proposed to implement the translation of geometric models in a neutral STEP format, which reduces the number of required translators. It is noted that the STEP format is recognized by various CAE systems that implement the finite element method (Autodesk Mechanical Desktop, Bentley Microstation, CATIA V4, CATIA V5, MSC Patran/Nastran, UGS PLM Solutions NX). The characteristics of the OBJ format used for storing a geometric model in the ArchiCAD CAD system and the STEP format used for data exchange with CAE systems are studied. A translator of geometric models of single-contour geodesic shells from ArchiCAD to STEP format in the Visual Basic programming language has been developed. For this purpose a syntactically oriented approach was used. The translator has a graphical user interface that makes it easier to use. The translator allows you to automate the exchange of data between the ArchiCAD CAD system and various CAE systems designed for strength analysis and supporting import from the STEP format. The applicability of the translator for the exchange of data on geometric models of single-contour geodesic domes with triangular plates between ArchiCAD and the Delcam Exchange converter program is verified. It is demonstrated that the STEP file format generated by the OBJSTEPTranslator is recognized by an external program.

Automation control system of 3d printing robotic platform with implemented wire + arc welding technology

Purpose. Development of the robotic platform automated control system architecture, development of the software control algorithm.
 Methodology. To implement the algorithm of the control program, computer modeling of thermal regimes in CAE systems is used. The basic parameters of the single layer printing technique were obtained by experimental use of the wire plus arc additive manufacturing (WAAM) technology.
 Findings. Requirements for manufacturability and printing quality of the manufactured parts were defined in the form of geometric dimensions, surface waviness, parameters of the desired microstructure state, residual stresses, maintaining of the optimal manufacturing speed. Based on the requirements of manufacturability analysis, an algorithm for the control program was developed. Robotic platform automated control system architecture with feedback device for the thermal mode control, parameters of the geometrical form of the manufactured part and weld pool were developed. Three -level hierarchical model, which gives an ability to consider in the process of 3D printing each level individually in terms of welding bead, layer and wall, was developed. The input data for the operation of the automated control system of the robotic platform using the technology of electric arc welding are determined. Basic geometrical parameters and the simple welding bead and the methods of overlapping of two or more beads were shown. Critical differences between ideal and real welding overlapping models were considered for necessity of taking into account whilst generating robot control software. Analysis of the possibilities for the CAE simulation of the three-dimensional printing using wire plus arc additive manufacturing technology is performed to determine the influence of the temperature parameters, mechanical loads, toolpath change, and based on the data obtained, it became possible to determine residual stresses and defects in manufactured parts.
 Originality. Robotic platform automated control system architecture with feedback device for the control of thermal mode, parameters of the geometrical form of the manufactured part and weld pool was developed. Three-level hierarchical model for the wire plus arc additive manufacturing (WAAM) technology was created. Software control algorithm which provides an opportunity to improve geometrical and mechanical properties of the manufactured parts was developed.
 Practical value. Development of an automated control system for 3D printing robotic platform with WAAM implemented technology, which will provide an opportunity for increase in the printing accuracy of the manufactured parts and will help to reduce manufacturing time.

Combine head mover designing by modern software using

The development of technical solutions without using of modern computer-aided design systems is not possible at the present stage. The using of CAD and CAE systems made possible to reduce costs and save time for development of combine head mover. As a CAD and CAE systems were used KOMPAS-3D and APM WinMachine. As a result of a computational experiment, the minimum weight with the required structural strength and rigidity of the combine head mover design was obtained. Obtained data were the base of combine head mover prototype manufacturing and its successful test.

Determination of the boundary conditions for the value of deformation from contact pressures in press-fit joints

The main reason that impedes the introduction of assembly methods using plastic deformation in mechanical assembly production is the difficulty in assigning optimal technological parameters that provide the required quality of the connection. The article considers the problem of preserving within the tolerance field after the pressing, deviations of dimensions, shape and mutual position of the surfaces of joints with an interference fit of the «sleeve-body» type. The results of studies of the deformation of the sleeve bore from the contact pressure in the node at interference fit are presented. The known solutions of the Lamé problem are supplemented with dependencies that take into account the uneven distribution of pressure along the joint axis, the error in the geometry of the contact surfaces shape, and a decrease in the tightness because of crushing microroughnesses. The results of analytical modeling of assembly deformation and finite element modeling are characterized by functional identity, which makes future research promising for obtaining corrective coefficients to be used to create software applications for CAE systems. The stated problem is urgent since the correction of the errors of the sleeve in the body due to the deformation from the pressing forces is a process technologically difficult and economically expensive as a rule because of the assembly location