ANSYS Environment Research Articles

Directionally Oriented Reinforcements of Warp-Knitted Fabrics for Composite Preforms.

This paper focuses on the development of a methodology for the directional structural modification of warp-knitted fabrics by sewing on carbon fiber tapes. Four-, five-, and six-axial geometric systems were designed to optimize the qualitative distribution of stresses on the surface of the tested product. Through a numerical experiment in the ANSYS environment, the impact of the change in the axiality of a textile structure on the mechanical properties of the modeled geometric configuration was assessed. This analysis was experimentally verified by measuring the multiaxial force distribution on the knitted surface, which demonstrated that Variant 7, with six axes 30° apart, was the most favorable.

АНАЛІЗ ХАРАКТЕРИСТИК ЛОКАЛЬНОГО НАПРУЖЕНО-ДЕФОРМОВАНОГО СТАНУ З'ЄДНАННЯ МЕТАЛЕВОГО КОМЛЯ З КОМПОЗИТНОЮ ЛОПАТТЮ ПОВІТРЯНОГО ГВИНТА

The article discusses the possibility of modeling the stress-strain state (SSS) of the connection of the metal butt with the composite cylindrical part of the blade using the specialized ANSYS software application and its Composite PrepPost module. Created connection models in ANSYS environment. The optimal designs for connecting the metal butt and composite material have been determined. For a simplified calculation of the connection strength, only the influence of the centrifugal force arising during operation of the screw is taken into account. In the ANSYS software package, a static load of the connection was carried out, which makes it possible to evaluate the nature of the stress distribution in the connection. A butt model and a finite element connection mesh were created. For the calculation, the characteristics of the materials of the blade elements are given. To determine a rational structural-power connection scheme, varying parameters were selected: the number of rows of spikes along the radius, the number of spike belts and the arrangement of the butt spikes. The dependence of the voltage in the composite part of the connection on the arrangement of the butt spikes was obtained. The shape and length of the spike were analyzed. The dependence of voltage on the radius of curvature of the tenon was obtained. The stress-strain state of a tenon-rounded flange is shown in ANSYS. The dependences of voltage on the length of the spike were obtained. The calculation showed that the length of the tenon L has a significant effect on the strength characteristics of the connection between the flange and the composite layer. To determine the rational position of the stud, a calculation was carried out in the ANSYS environment with a shift of all rows of studs by the amount K from the extreme position in engagement with the composite layer and a change in the linear order of the studs to a staggered one. The results of the calculation in the ANSYS environment are presented as a dependence of stress on the displacement K. A flange model is presented, where the stud arrangement is staggered, and the result of the stress calculation in the ANSYS environment. The calculation showed that changing the order of the studs from linear to staggered reduces the maximum stress to 385 MPa. The hydraulic pressure tests confirmed the calculation results. The simulation results showed a significant improvement in the mechanical performance of the joints with minimal design costs.

Bi-orthogonality relations: general formulation, conversion to the FE format, and application for analysis of homogeneous and periodic waveguides

Bi-orthogonality relations are a powerful tool to solve complicated wave propagation problems in a surprisingly simple way. For any symmetric waveguide, these relations identify so-called Class A and Class B boundary conditions, for which eigenfrequencies and eigenmodes of a slice of waveguide provide dispersion diagrams of propagating waves and (for periodic wave-guides) location of pass- and stop-bands. It is a straightforward matter to convert these 'class-consistent' boundary conditions to the FE format and use standard FE modal analysis software to study properties of waveguides of arbitrary complexity. However, an application of this methodology, especially for periodic waveguides, is challenged by the necessity to track mode shapes and pair Class A and B eigenfrequencies into their modal families. A novel algorithm to resolve this issue is proposed and tested on post-processing results of modal analysis in the AN-SYS environment. Underlying theory of bi-orthogonality, analytical solutions of benchmark problems, and FE case-studies are presented and explained.

Characterization of the hydrostatic core and plastic zone that form during Brinell and Vickers hardness tests

Abstract During a hardness test, a hydrostatic core and a plastic zone are formed under the impression due to the load. The size and shape of the hydrostatic core and the plastic zone are greatly influenced by the tested material, the loading force and the shape of the indenter. In this study, we examine in detail the characteristics of the hydrostatic core and plastic zone formed during a Brinell and Vickers hardness test with the same (bilinear) hardening material model and with the same load using the finite element method in the ANSYS environment. The results of our resarch is concluded that the characteristics under the indenter can be determined well with finite element modeling and in the case of the Vickers procedure, the ratio of the hydrostatic core to the plastic zone is greater for all loads as in the case Brinell method.

Numerical and Experimental Analysis of the Vacuum Corn Seed Degassing System

Vacuum degassing of seeds is a basic preliminary stage of the treatment process to improve the viability of seeds of various crops. In this work, the degassing process of corn seeds was experimentally and numerically analyzed by removing air or other gases from around the seeds, specifically from the seed coating, in a rough vacuum chamber. Two complementary variants were employed to understand and optimize this process to improve the quality and germination rate of the seeds. The average germination percentage on the first day was about 98%, and the germination speed of 5.0 days. Several experiments were conducted with well-established durations of 10 min and masses of 5 kg and masses of corn seeds at different temperatures to observe and record the behavior of the system, facilitating the modeling of the degasification process in the vacuum compartment. Modeling the degasification operation in the vacuum chamber allowed for determining the pressure profiles on the vacuum chamber and its lid. Numerical simulations were either conducted using a simulation program developed in the Visual Basic Applications (VBA) language for Microsoft Excel to model the degassing process in the vacuum chamber or with the assistance of specialized software (transient structural analysis and simulation program in the ANSYS Workbench environment). Statistical analysis of the correlation between experimental and estimated pressure values revealed that both the proposed mathematical model and the solution method are well-chosen, with differences expressed through the absolute error (EA) being very small, only 1.425 mbar. Structural dynamic analysis carried through the Finite Element Method (FEM) highlights that the chosen materials for manufacturing the vacuum chamber vessel (316 stainless steel—yield strength 225 MPa and tangent modulus 2091 MPa) or the chamber lid (transparent acrylic plastic—yield strength 62.35 MPa and shear modulus 1445.3 MPa) are durable and capable of withstanding the desired pressure and temperature demands in the seed treatment process. Additionally, through structural dynamic analysis, it was possible to study the deformation of system components, providing a detailed perspective on their structural distribution. Thus, the paper aims to improve the quality and survival/germination rate of corn seeds as an important step to improve corn yield through simulations and analyses (numerical and experimental) of the vacuum corn seed degassing system. The degassing process of the vacuum chamber was simulated with a simulation program developed for Microsoft Excel for Microsoft 365 MSO (Version 2401 Build 16.0.17231.20236) 64-bit in the VBA language and software (transient structural dynamic analysis in the ANSYS environment through FEM). Vacuum degassing of corn seeds involves the removal of air or other gases around the seeds or products, which is crucial in various fields such as the food, pharmaceutical, or space technology industries.

Development of a 2-dimensional thermal calculation method to estimate silicone oil's temperature distribution in viscous torsional vibration dampers

AbstractHigh-performance internal combustion engines are subject to severe torsional vibrations which result from uneven gas and inertial loads. Fatigue damage occurs if the frequency of these undesired oscillations matches the resonance frequency of the crankshaft and the driven engine elements. This phenomenon can be avoided by the application of visco-dampers whose working fluid is high-viscosity silicone oil. Since silicone oil is exposed to a significant amount of heat load during operation, it is essential to calculate the temperature distribution in a relatively easy, quick, and cost-efficient way for lifetime estimation purposes. The aim of this article is to develop a reliable, fast, and accurate finite difference-based numerical method for steady-state thermal calculations for arbitrary damper sections. The developed MATLAB code calculates the temperature field of the damping fluid together with all components in a radial cross-section at given operational conditions. The accuracy of the developed thermal calculation method has been tested in a 3-dimensional – 2-dimensional two-step verification process by finite element and finite volume-based advanced engineering software in ANSYS environment. Furthermore, the original Iwamoto equation available in the literature has been updated to provide more accurate surface temperature results based on the simulations' outcome gained by the finite volume method.

Dynamic response of the annular hole defect under ultrasonic in brick

In recent years, ultrasonic diagnostics and health monitoring of buildings have become widely used in construction. However, the accuracy of ultrasonic devices in heterogeneous media such as concrete, brick and other elements is fraught with difficulties and leads to errors. The article considers the problem of the dynamic response of a defect in the form of a cylindrical hole in a brick during ultrasonic diagnostics. The problem was simulated in the ANSYS environment using the finite element method. A dynamic stimulus with a frequency of 60 kHz is applied in the immediate vicinity of the defect and the response is numerically determined at a point symmetrically located from the defect. The results of numerical analysis in the form of fields of displacements, stresses and deformations have been obtained. It is shown that to effectively determine the geometry of a defect in the form of a hole, it is necessary to analyse data on the 3rd or 4th half-waves of the response.

Development of models and analysis of temperature fields of new energy-saving enclosing structures with an air layer

The author of the article propose new models of energy-saving envelope structures with air interlayers. To calculate the temperature fields in the enclosing structures they used the finite element modeling method in ANSYS environment. The authors analyzed the temperature fields at different variants of the outdoor temperature index. To calculate the temperature field in the envelope was used finite element model of the envelope, in which the influence of the ventilated air layer is replaced by the Convection type boundary condition with the temperature value. The result of the study is the analysis of temperature fields of new models of enclosures in different variants. So when analyzing the values of thermal resistance of traditional (scheme-1) and developed envelope structures (schemes 2-4) it was found that the thermal resistance of scheme-2 relative to the traditional scheme-1 value of thermal resistance at minimum temperature is 6.2 % higher. The authors also calculated by analogy the thermal resistance index at maximum temperature (4.5 %), at five days (5.8 %) and for the month of April (5.7 %). The analysis showed that scheme-2 is the most efficient of the new envelope schemes considered. In the comparative analysis of schemes - 3,4 with traditional scheme-1, the value of thermal resistance showed a negative effect. The authors determined that the temperature field is insignificantly different when using horizontal and vertical closed channels. The developed new energy-saving designs of external enclosure with air layer can be used in the design and construction of buildings, as well as in the teaching of relevant disciplines in universities.

Static strength and crashworthiness analysis of a train cowcatcher at a running speed of 160 km/h

The cowcatcher is one of the unique devices at the front end of the train, which can remove obstacles on the track by crashing before the vehicle body to ensure the safety of the train. When a collision accident happens, the cowcatcher serves as the first energy-absorbing structure to dissipate and guide the collision energy. The design of the existing cowcatcher of multiple units generally focuses on the good ability to remove obstacles, while the secondary function, the crashworthiness of orderly deformation under collision, still needs further research. In this study, a finite element model of structural static load and collision analysis was established under standard EN 15227, with the cowcatcher for 160 km/h train as the prototype. Then the solution and simulation process was accomplished under the environment of ANSYS and LS-DYNA. The analysis results showed that the structural static strength of the current cowcatcher met the requirements of the standard EN 15227, and the longitudinal stiffness was evenly distributed. When removing the obstacles with low mass, the impact force was small and the structure would not produce obvious deformation; when removing the obstacles with large mass, the impact force was large and the shear fracture might occur at the connection of the cowcatcher.

Numerical Simulation and Analysis of Hydraulic Turbines Based on BIM for Sustainable Development

Hydropower is considered to be an important way to achieve the sustainable development goal of human progress. The performance of turbines is very important to the safety and stability of hydropower stations. Most of the hydraulic turbine performance studies only use Computational Fluid Dynamics (CFD) for performance simulation, lacking the integration of Building Information Modeling (BIM) technology and CFD. Therefore, a performance analysis model of a Francis turbine based on BIM was put forward in this paper. The BIM software OpenBuildings Designer CONNECT Edition Update 10 was used to build the hydraulic turbine model, and then the BIM model was transferred to the CFD numerical simulation platform ANSYS through the intermediate format conversion. In the ANSYS environment, the numerical simulation of different working conditions was carried out with the help of Fluent 2021 R1 software. The numerical simulation results show that the fluid velocity gradient in the volute was 2~3 m/s under the three working conditions, which was relatively stable. The water flow could progress the guide vane mechanism at a higher speed, and the drainage effect of the volute was better. There were some negative pressure areas at the back of the runner blades and the inlet of draft tube, and the negative pressure value was as high as −420,000 Pa and −436,842 Pa under maximum head conditions, which were prone to cavitation erosion. It is proven that BIM supported the hydraulic turbine performance analysis and provided a geometric information model for hydraulic turbine CFD numerical simulation, meaning that the performance analysis model based on BIM is feasible. This study can expand the application value of BIM and provide guidance for the study of hydraulic turbine numerical simulation using BIM technology in combination with CFD methods.

"STUDY OF THE MECHANICAL CHARACTERISTICS OF FDM (3D PRINTED) PARTS: EMPIRICAL AND COMPUTATIONAL METHODS"

"Fused deposition modelling, alternatively referred to as Fused Filament Fabrication, is an additive manufacturing technique that has garnered significant attention across various industries due to its diverse applications. This research investigates the ultimate tensile strength and elastic modulus of 3D-printed Polylactic acid samples, following the ISO-527-2-2012 standard. The mechanical performance of the created parts is considered from both experimental and computational points of view. The finite element method within the ANSYS environment was employed for computer-based load and strength calculations. Tensile specimens are fabricated using the Fused deposition modelling approach. The experimental outcomes were utilised to derive all the essential engineering constants required for evaluating the mechanical behaviour. The validity of the theoretical model has been confirmed through a comprehensive comparison with a substantial volume of experimental data, exhibiting mean errors of approximately 1 %. The objective of this research is to assess the effectiveness and efficacy of analytical models in predicting the structural and mechanical behaviour of components produced through fused deposition modelling. Keywords: additive technology, fused deposition modelling (FDM), PLA, mechanical properties, analytical model."

Modeling and Calculation of Improved Centrifuged Reinforced Concrete Columns with Variotropic Structure

The use of vibro-centrifugation technology allows the manufacture of variotropic structures that are inhomogeneous in the annular section and have different characteristics along the section thickness. Hardening of the outer layers allows the structure to better resist bending conditions, however, the behavior of the variotropic column under central and eccentric compression remains unexplored. This article considers the problem of compression of hollow columns made of homogeneous concrete that is non-uniform in the annular section (variotropic), and is reinforced with steel reinforcing bars at different values of the load application eccentricity. Variotropic concrete obtained by vibro-centrifugation technology has a stronger outer part and a less durable inner part. The strength of a homogeneous column corresponds to the strength of the middle part of variotropic concrete. The problem was solved numerically in the ANSYS environment for a vertical column rigidly clamped at the bottom edge and loaded with eccentricity at the top edge. Three types of eccentricity are considered; e/r = 0, 0.16 and 0.32 (respectively 0 mm, 0.24 mm and 48 mm). The results of the solution in the form of stress fields, deformations and a pattern of crack development in a spatial setting are obtained. The results showed that for central compression, a homogeneous column has a better bearing capacity of 3.6% than a variotropic one. With the values of eccentricity e/r = 0.16 and 0.32, the variotropic column has a higher bearing capacity (by 5.5% and 6.2%) than the homogeneous one and better resists the development of cracks. The significance of the study lies in the practical application of the proposed approach, developed on a research basis, for non-trivial and complicated operating conditions of columns. This study influences the development of reinforced concrete structures and applies scientific findings to engineering practice.

Structural Analysis of Squat Rack using Finite Element Approach

In this work, a Finite Element Analysis (FEA) of Squat Rack is presented for the Mild steel (AISI 1045) and Stainless steel (AISI 304) materials. The frame, top bar and J Hook of squat rack are modelled and analysed in ANSYS environment. At first, the static analysis is carried out for predicting the nodal displacements and stresses. Afterwards, the modal Analysis of the developed FE model is carried out and five mode shapes are obtained at five different natural frequencies. For both the analyses, a beam 188 element is selected. The results of static and modal analysis were plotted for the selected materials. By comparison of all the results, it is inferred that the AISI 304 stainless steel produced minimal displacements and stress values. Finally, it is observed that the performance of FE models and their solutions are accurate and robust.

Dynamic Characteristics of a Rotating Blade with a Dovetail Fixture

Considering rotation-induced centrifugal stiffening, spin softening, and Coriolis effects, the reduced dynamic model of a rotating blade with a dovetail fixture is established in the ANSYS environment via the fixed-interface method for higher computational efficiency and lower memory consumption. Then some parameters such as rotating speed, friction factor, and stator blade number affecting the nonlinear vibration responses of the system under the combined actions of aerodynamic force, centrifugal force, and gravity are elaborately discussed. The results show that: (1) the contact-induced nonlinearity between the tenon and the mortise mainly results in the frequency multiplications of the aerodynamic excitation frequency; (2) a larger friction factor results in a lower magnitude of contact pressure and a higher resonance frequency, while a larger stator blade number results in a lower magnitude of the uniform and continuous contact pressure distribution; (3) the excitation of the resonant mode caused by the aerodynamic force is primarily characterized by the first-order bending mode of the system.

Evaluation of Accelerator Pedal Strength under Critical Loads Using the Finite Element Method

The core idea of the research consists in a formulation of boundary conditions of a mechanical accelerator pedal’s strength in an Ansys environment, whose conditions are equivalent to full-scale tests under the critical loads defined by the UNECE’s Regulation No. 13. The lack of regulatory requirements for the strength of pedal types other than brake pedals is a major gap in vehicle certification, especially when it comes to agricultural machinery. In such cases, the authors suggest being guided by UNECE R 13 regarding the strength of the accelerator and other types of pedals and checking their behavior under loads of at least 1000 N. The real value of the yield strength of the material (Silumin 4000) is very important, both in the physical real-life experiments and in FEA simulation. The critical case of a short-term shock loading of the pedal in its extreme position has been considered separately. With the help of the Ansys Explicit Dynamics module, results of a pedal’s behavior were obtained; it lost its integrity and suffered destruction. It is also necessary to check the intermediate stress values depending on the loads for direct and hybrid tasks using the Transient Structural module in order to estimate other critical cases of the pedal behavior.

Friction heating and stress-strain state of ventilated disc brakes

This paper describes the study of ventilated car disc brakes stress-strain conditions and friction under the pressure using the ANSYS environment. Such influencing factors are taken into account in the course of research as angular speed value, the pressure of the pads on the disk, the nature of the load application, convection, thermal expansion, etc. Computer modelling of the stress field and the transient thermal field in the area of contact between the pads and the disk is provided by the method of sequential thermostructural communication of the intermediate states of the brake model directly in the ANSYS Coupled Field Transient environment. Besides, the ANSYS calculations were also performed based on the primitive assembly model of two steel blocks (the discrepancy was less than 3%) to determine the identity of the theoretical knowledge about the heating of bodies as a result of the work to overcome frictional forces. Finally, a high level of calculation results convergence by analytical formulas and computer modelling was established. Since this approach justified itself, its principles were taken as a basis in the calculations of ventilated disc brakes of cars, which significantly facilitates their application, knowing the area of the active part of the disc (the rest of the boundary conditions are typical and correspond to the normal operating modes of the vehicle).

Analysis of the influence of thermal insulation material on the thermal resistance of new facade structures with horizontal air channels

The research proposes new energy-saving façade constructions with closed horizontal vents, the analysis of which was carried out in ANSYS environment by the finite element method. The result of the analysis of the thermal resistance of the developed facade structures shows that a decrease in the volume of thermal insulation material by 31.25% leads to a significant decrease in the thermal resistance of the fence for all values of the external temperature, that is, at the absolute minimum by 26.31%, at the absolute maximum temperature by 26.41%, at the average temperature of the coldest five-day security 0.92 by 26.47% and at an average temperature of the first month after the end of the heating period (April) 26.54%. A similar decrease was also observed when comparing facade structures with a heat-reflecting screen: at an absolute minimum temperature of 24.9%, at an absolute maximum temperature of 24.76%, at an average temperature of the coldest five-day security of 0.92 by 24.28% and at an average temperature of the first month after the end of the heating period (April) of 24.07%. At the same time, during the analysis, it was additionally found that with the same volume indicator of the heat-insulating material in the developed new façade constructions, the heat-reflective screen presence results in an increase in the heat resistance value by 10–19%, depending on the climatic conditions of the outdoor environment. Thus, the research results can be used in buildings’ design and construction in order to reduce heat consumption and energy saving.

Thermal and stress-strain state of friction pairs in ventilated disc brakes of lightweight vehicles

The work is dedicated to the thermal behavior and stress-strain state of ventilated disc brakes installed in the lightweight vehicles (scooters, electric bikes, ATVs, etc.) using ANSYS environment in various experiment modes. Modeling of the temperature distribution in the rotor (disc) and the corresponding brake pads is determined taking into account a number of factors and input parameters during the braking operation: the amount of rotation speed, the gap between the pads and the disc, the speed of load application, thermal expansion, etc. Numerical modeling of the transient thermal and the stress fields in the area of contact between the pads and the rotor is carried out by the method of sequential thermostructural connection of the intermediate calculation states of the brake model in the ANSYS Coupled Field Transient environment. For a comprehensive assessment of brake behavior, our research considers two load approaches: constant long-term (20 s) with an influence factor in the form of thermal expansion as a result of contact pair friction; linear load from the pads on the disс with a corresponding increase in pressure up to the moment when the rotation of the system is blocked. Our research presents an assessment of the rotor ventilation channels influence on the nature of the contact spot with the brake pads (open far-field contact, sliding contact, sticking contact, etc.). In addition, it is demonstrated that despite the linear increase in pads pressure on the rotor, the graphs of temperatures, volume (thermal expansion) and stresses are of parabolic character with a disproportionate increase in indicators. Such a result forces us to come to the conclusion that it is not possible to predict the behavior of the brakes based on the analysis during a short period of time of the experiment - conducting long-term analytical studies is extremely important in the case of brakes

Structural Optimization of Long and Flexible Composite Cover with Topography Method and Examination of Frequency Values

In this study, the finite element model of the long, thin, and flexible carbon fiber reinforced composite cover design prepared using the Unigraphics NX program CAD module was analyzed in ANSYS program. Topography optimization was performed by transferring the analysis results to the GENESIS program. The cover rib created after optimization was combined with the initial design, and necessary corrections were made in the design based on the topography guide. The rib design, created by conventional methods, weigh the same as the optimum design, is combined with of the initial design. Modal analysis of initial, conventional rib and optimum rib design was performed in ANSYS environment. When the findings were evaluated it was observed that the composite cover, which was remodeled after topography optimization, increased by 33.3% compared to the initial design, while its natural frequency (mode 2) increased approximately 1.6 times. In addition, the lowest moment of inertia value has been obtained in the cover design with optimum design geometry. Then, the conventional design, which has the same mass as the new design, was compared and it was revealed by the data that the new design was more resistant. According to the results obtained, the most suitable rib geometry to be preferred for this and similar types of long and flexible structures to have a more resistant structure has been determined.

Feasibility study of topology optimization of the control system frame for the missile with canard configuration

PurposeThe purpose of this paper is to describe the new method for optimizing the topology of the control system frame for a canard missile to create its efficient model. Determining the minimum volume of the part risked losing some of the mechanical interfaces and functionality required of the frame. The proposed method must cope with these requirements and include a validation loop of the improved solution proposed by the software. The processing of the mathematical model to a printable form must take into account manufacturing technologies limitations and appropriate curvature continuities to avoid stress concentrations.Design/methodology/approachReal examples from the aerospace industry are presented and the process of determining a prototype is described. The optimization assumed leaving the largest volume of the domain. Strength analyses were performed on both the assembly fasteners and the robust prototype. Once all boundary conditions were validated, topological optimization was performed in the ANSYS environment. The algorithm of the optimization was presented.FindingsObtained fatigues showed the vast potential of topology optimization, efficient method of weight reduction in specific situations. It can be considered as an innovative approach to the manufacturing of products with a structure focused on the best possible correlation of weight and strength, for example of a canard rocket.Originality/valueThe paper introduces precise manufacturing technology of the inner frame for the missile’s control system, which ensures sufficient properties of the material, known as EBM.