Research

30 pages, 5370 KiB

Open AccessEditor’s ChoiceArticle

A Method for Predicting the Creep Rupture Life of Small-Sample Materials Based on Parametric Models and Machine Learning Models

by Xu Zhang, Jianyao Yao, Yulin Wu, Xuyang Liu, Changyin Wang and Hao Liu

Materials 2023, 16(20), 6804; https://doi.org/10.3390/ma16206804 - 22 Oct 2023

Viewed by 1259

Abstract

In view of the differences in the applicability and prediction ability of different creep rupture life prediction models, we propose a creep rupture life prediction method in this paper. Various time–temperature parametric models, machine learning models, and a new method combining time–temperature parametric [...] Read more.

In view of the differences in the applicability and prediction ability of different creep rupture life prediction models, we propose a creep rupture life prediction method in this paper. Various time–temperature parametric models, machine learning models, and a new method combining time–temperature parametric models with machine learning models are used to predict the creep rupture life of a small-sample material. The prediction accuracy of each model is quantitatively compared using model evaluation indicators (RMSE, MAPE, R²), and the output values of the most accurate model are used as the output values of the prediction method. The prediction method not only improves the applicability and accuracy of creep rupture life predictions but also quantifies the influence of each input variable on creep rupture life through the machine learning model. A new method is proposed in order to effectively take advantage of both advanced machine learning models and classical time–temperature parametric models. Parametric equations of creep rupture life, stress, and temperature are obtained using different time–temperature parametric models; then, creep rupture life data, obtained via equations under other temperature and stress conditions, are used to expand the training set data of different machine learning models. By expanding the data of different intervals, the problem of the low accuracy of the machine learning model for the small-sample material is solved. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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16 pages, 26013 KiB

Open AccessArticle

Numerical Study of the Plastic Zone at the Crack Front in Cylindrical Aluminum Specimens Subjected to Tensile Loads

by Lenin Abatta-Jacome, Antonia Lima-Rodriguez, Antonio Gonzalez-Herrera and Jose Manuel Garcia-Manrique

Materials 2023, 16(20), 6759; https://doi.org/10.3390/ma16206759 - 19 Oct 2023

Viewed by 784

Abstract

Cylindrical specimens are of great interest in analyzing mechanical elements’ behavior and investigating phenomena with biaxial loads. It is necessary to identify the behavior of the crack front along the thickness to interpret these results, which are usually based on the hypothesis of [...] Read more.

Cylindrical specimens are of great interest in analyzing mechanical elements’ behavior and investigating phenomena with biaxial loads. It is necessary to identify the behavior of the crack front along the thickness to interpret these results, which are usually based on the hypothesis of a straight crack and the observation of the outer face of the crack front. Based on the work carried out on compact tension type specimens, this work proposes adapting this methodology to cylindrical specimens, adapting the previous finite element models. Cylindrical specimens provide an asymmetric behavior influenced by the radius, where the CT (compact tensile) specimen can be considered the extreme infinite radius case. Combinations of the load level and radius values help us simulate the crack’s behavior under intermediate hypotheses between a plane crack theory and a three-dimensional one. The plastic strain around the crack front will be analyzed as a function of the thickness and the load level applied. The results allow us to validate the numerical methodology and establish the differentiated behaviors of the plastic zones close to the outer and inner radii. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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16 pages, 4011 KiB

Open AccessArticle

Feasibility Analysis of Calcium Carbonate Particle Trajectory Simulation in a Dual Horizontal Shaft Mixer

by Guozheng Song, Faguo Huang and Jiafang Pan

Materials 2023, 16(17), 5999; https://doi.org/10.3390/ma16175999 - 31 Aug 2023

Cited by 1 | Viewed by 590

Abstract

This article aims to investigate the feasibility of using discrete element software EDEM 2022.0 to simulate the trajectory of artificial marble patterns in a dual horizontal shaft mixer. Research was conducted on the mixing uniformity of particles in the mixing chamber, and the [...] Read more.

This article aims to investigate the feasibility of using discrete element software EDEM 2022.0 to simulate the trajectory of artificial marble patterns in a dual horizontal shaft mixer. Research was conducted on the mixing uniformity of particles in the mixing chamber, and the optimal speed range for particle mixing was established. By simulating the trajectory of pigment particles, the trajectories of the particles at different positions of the stirring paddle were obtained, and the trajectories were compared with the measured results. In the study of uniform particle mixing, the Lacey index at different speeds was compared, and the optimal speed range was established between 40 RPM and 60 RPM. Based on this, the particle trajectory simulation found that the motion trajectories of particles at different positions of the stirring paddle varied significantly. The particles in the stirring paddle rod exhibit a gradual trend, in which they gradually decrease as they approach the head of the stirring paddle. Finally, the feasibility of this method was established by comparing the simulated and actual patterns through proportional replication of the mixing process, and it was discovered that the two were similar. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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15 pages, 5849 KiB

Open AccessArticle

Cavitation Erosion Prevention Using Laser Shock Peening: Development of a Predictive Evaluation System

by Wenlong Li, Hongbing Yao, Zhipeng Ding, Yuanhang Zhou, Pengyu Wei, Jiang Yue, Wei Su and Weihua Zhu

Materials 2023, 16(14), 5096; https://doi.org/10.3390/ma16145096 - 19 Jul 2023

Viewed by 741

Abstract

Marine flow-passing components are susceptible to cavitation erosion (CE), and researchers have worked to find ways to reduce its effects. Laser Shock Peening (LSP), a material strengthening method, has been widely used in aerospace and other cutting-edge fields. In recent years, LSP has [...] Read more.

Marine flow-passing components are susceptible to cavitation erosion (CE), and researchers have worked to find ways to reduce its effects. Laser Shock Peening (LSP), a material strengthening method, has been widely used in aerospace and other cutting-edge fields. In recent years, LSP has been used in cavitation resistance research. However, the current LSP research does not realize a comprehensive predictive assessment of the material’s CE resistance. This paper uses m stresses to develop a comprehensive set of strengthening effect prediction models from LSP to CE using finite element analysis (FEA). Results show that the LSP-1 sample (4 mm spot, 10 J energy) introduced a compressive residual stress value of 37.4 MPa, better than that of 16.6 MPa with the LSP-2 sample (6 mm spot, 10 J energy), which is generally consistent with the experimental findings; the model predicts a 16.35% improvement in the resistance of LSP-1 sample to water jet damage, which is comparable to the experimental result of 14.02%; additionally, interactions between micro-jets do not predominate the cavitation erosion process and the final CE effect of the material is mainly due to the accumulation of jet-material interaction. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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10 pages, 413 KiB

Open AccessEditor’s ChoiceArticle

Influence of Traps and Lorentz Force on Charge Transport in Organic Semiconductors

by Seema Morab, Manickam Minakshi Sundaram and Almantas Pivrikas

Materials 2023, 16(13), 4691; https://doi.org/10.3390/ma16134691 - 29 Jun 2023

Cited by 2 | Viewed by 843

Abstract

Charge transport characteristics in organic semiconductor devices become altered in the presence of traps due to defects or impurities in the semiconductors. These traps can lead to a decrease in charge carrier mobility and an increase in recombination rates, thereby ultimately affecting the [...] Read more.

Charge transport characteristics in organic semiconductor devices become altered in the presence of traps due to defects or impurities in the semiconductors. These traps can lead to a decrease in charge carrier mobility and an increase in recombination rates, thereby ultimately affecting the overall performance of the device. It is therefore important to understand and mitigate the impact of traps on organic semiconductor devices. In this contribution, the influence of the capture and release times of trap states, recombination rates, and the Lorentz force on the net charge of a low-mobility organic semiconductor was determined using the finite element method (FEM) and Hall effect method through numerical simulations. The findings suggest that increasing magnetic fields had a lesser impact on net charge at constant capture and release times of trap states. On the other hand, by increasing the capture time of trap states at a constant magnetic field and fixed release time, the net charge extracted from the semiconductor device increased with increasing capture time. Moreover, the net charge extracted from the semiconductor device was nearly four and eight times greater in the case of the non-Langevin recombination rates of 0.01 and 0.001, respectively, when compared to the Langevin rate. These results imply that the non-Langevin recombination rate can significantly enhance the performance of semiconductor devices, particularly in applications that require efficient charge extraction. These findings pave the way for the development of more efficient and cost-effective electronic devices with improved charge transport properties and higher power conversion efficiencies, thus further opening up new avenues for research and innovation in this area of modern semiconductor technology. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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20 pages, 9327 KiB

Open AccessEditor’s ChoiceArticle

Numerical Study of Ti6Al4V Alloy Tube Heated by Super-Frequency Induction Heating

by Cheng Liu, Jingtao Han, Ruilong Lu, Jiawei Liu and Xiaoyan Ma

Materials 2023, 16(11), 3938; https://doi.org/10.3390/ma16113938 - 24 May 2023

Cited by 1 | Viewed by 889

Abstract

Ti6Al4V alloys have a narrow processing window, which complicates temperature control, especially during large-scale production. Therefore, a numerical simulation and experimental study on the ultrasonic induction heating process of a Ti6Al4V titanium alloy tube were conducted to obtain stable heating. The electromagnetic and [...] Read more.

Ti6Al4V alloys have a narrow processing window, which complicates temperature control, especially during large-scale production. Therefore, a numerical simulation and experimental study on the ultrasonic induction heating process of a Ti6Al4V titanium alloy tube were conducted to obtain stable heating. The electromagnetic and thermal fields in the process of ultrasonic frequency induction heating were calculated. The effects of the current frequency and current value on the thermal and current fields were numerically analyzed. The increase in current frequency enhances the skin and edge effects, but heat permeability was achieved in the super audio frequency range, and the temperature difference between the interior and exterior of the tube was less than 1%. An increase in the applied current value and current frequency caused an increase in the tube’s temperature, but the influence of current was more prominent. Therefore, the influence of stepwise feeding, reciprocating motion, and stepwise feeding superimposed motion on the heating temperature field of the tube blank was evaluated. The coil reciprocating with the roll can maintain the temperature of the tube within the target temperature range during the deformation stage. The simulation results were validated experimentally, which demonstrated good agreement between the results. The numerical simulation method can be used to monitor the temperature distribution of Ti6Al4V alloy tubes during the super-frequency induction heating process. This is an economical and effective tool for predicting the induction heating process of Ti6Al4V alloy tubes. Moreover, online induction heating in the form of reciprocating motion is a feasible strategy for processing Ti6Al4V alloy tubes. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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18 pages, 1988 KiB

Open AccessArticle

Theoretical Tolerance Modelling of Dynamics and Stability for Axially Functionally Graded (AFG) Beams

by Jarosław Jędrysiak

Materials 2023, 16(5), 2096; https://doi.org/10.3390/ma16052096 - 04 Mar 2023

Cited by 4 | Viewed by 1179

Abstract

Some considerations of slender elastic nonperiodic beams are shown in this paper. These beams have a functionally graded structure on the macro-level along the x-axis, and a nonperiodic structure on the micro-level. The effect of the size of the microstructure on the [...] Read more.

Some considerations of slender elastic nonperiodic beams are shown in this paper. These beams have a functionally graded structure on the macro-level along the x-axis, and a nonperiodic structure on the micro-level. The effect of the size of the microstructure on the behavior of the beams can play a crucial role. This effect can be taken into account by applying the tolerance modelling method. This method leads to model equations with slowly varying coefficients, some of which depend on the microstructure size. In the framework of this model, formulas of higher order vibration frequencies related to the microstructure can be determined, not only for the fundamental lower-order vibration frequencies. Here, the application of the tolerance modelling method was mainly shown to derive the model equations of the so-called general (extended) tolerance model and standard tolerance model, describing dynamics and stability for axially functionally graded beams with the microstructure. A simple example of free vibrations of such a beam was presented as an application of these models. The formulas of the frequencies were determined using the Ritz method. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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17 pages, 18538 KiB

Open AccessArticle

Estimation of the Edge Crush Resistance of Corrugated Board Using Artificial Intelligence

by Tomasz Garbowski, Anna Knitter-Piątkowska and Jakub Krzysztof Grabski

Materials 2023, 16(4), 1631; https://doi.org/10.3390/ma16041631 - 15 Feb 2023

Cited by 6 | Viewed by 1920

Abstract

Recently, AI has been used in industry for very precise quality control of various products or in the automation of production processes through the use of trained artificial neural networks (ANNs) which allow us to completely replace a human in often tedious work [...] Read more.

Recently, AI has been used in industry for very precise quality control of various products or in the automation of production processes through the use of trained artificial neural networks (ANNs) which allow us to completely replace a human in often tedious work or in hard-to-reach locations. Although the search for analytical formulas is often desirable and leads to accurate descriptions of various phenomena, when the problem is very complex or when it is impossible to obtain a complete set of data, methods based on artificial intelligence perfectly complement the engineering and scientific workshop. In this article, different AI algorithms were used to build a relationship between the mechanical parameters of papers used for the production of corrugated board, its geometry and the resistance of a cardboard sample to edge crushing. There are many analytical, empirical or advanced numerical models in the literature that are used to estimate the compression resistance of cardboard across the flute. The approach presented here is not only much less demanding in terms of implementation from other models, but is as accurate and precise. In addition, the methodology and example presented in this article show the great potential of using machine learning algorithms in such practical applications. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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14 pages, 3495 KiB

Open AccessArticle

Modified Compression Test of Corrugated Board Fruit Tray: Numerical Modeling and Global Sensitivity Analysis

by Tomasz Garbowski, Damian Mrówczyński and Jakub Krzysztof Grabski

Materials 2023, 16(3), 1121; https://doi.org/10.3390/ma16031121 - 28 Jan 2023

Cited by 3 | Viewed by 1526

Abstract

This article presents a modified configuration of the box compression test (BCT), which reflects the actual behavior of the vegetable or fruit trays during transport and storage. In traditional load capacity tests, trays are treated as classic transport boxes, i.e., they are compressed [...] Read more.

This article presents a modified configuration of the box compression test (BCT), which reflects the actual behavior of the vegetable or fruit trays during transport and storage. In traditional load capacity tests, trays are treated as classic transport boxes, i.e., they are compressed between two rigid plates, which does not take into account the specific geometry of this type of packaging. Both the boundary conditions and the loads acting on the tray were modified. The paper presents the concept of a new test, as well as numerical models and a sensitivity analysis of the modified BCT to the basic geometrical dimensions of the tray. The conducted research clearly shows that the proposed configuration of the load-bearing capacity test of a tray is closer to the actual operation of the packaging. As a result, most of the parameters that are not active under the conditions of the classical BCT become more important in the new configuration, which corresponds to the observations on the real performance of the packaging. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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20 pages, 6151 KiB

Open AccessArticle

Numerical Estimation of SAR and Temperature Distributions inside Differently Shaped Female Breast Tumors during Radio-Frequency Ablation

by Arkadiusz Miaskowski and Piotr Gas

Materials 2023, 16(1), 223; https://doi.org/10.3390/ma16010223 - 26 Dec 2022

Cited by 4 | Viewed by 1719

Abstract

Radio-frequency (RF) ablation is a reliable technique for the treatment of deep-seated malignant tumors, including breast carcinoma, using high ablative temperatures. The paper aims at a comparative analysis of the specific absorption rate and temperature distribution during RF ablation with regard to different [...] Read more.

Radio-frequency (RF) ablation is a reliable technique for the treatment of deep-seated malignant tumors, including breast carcinoma, using high ablative temperatures. The paper aims at a comparative analysis of the specific absorption rate and temperature distribution during RF ablation with regard to different female breast tumors. In the study, four tumor models equivalent to an irregular tumor were considered, i.e., an equivalent sphere and ellipsoid with the same surfaces and volumes as the irregular tumor and an equivalent sphere and ellipsoid inscribed in the irregular tumor. An RF applicator with a specific voltage, operating at 100 kHz inserted into the anatomically correct female breast, was applied as a source of electromagnetically induced heat. A conjugated Laplace equation with the modified Pennes equation was used to obtain the appropriate temperature gradient in the treated area. The levels of power dissipation in terms of the specific absorption rate (SAR) inside the naturalistically shaped tumor, together with the temperature profiles of the four simplified tumor models equivalent to the irregular one, were determined. It was suggested that the equivalent tumor models might successfully replace a real, irregularly shaped tumor, and the presented numeric methodology may play an important role in the complex therapeutic RF ablation process of irregularly shaped female breast tumors. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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9 pages, 2631 KiB

Open AccessArticle

Tensile Stresses in the Coating with Interlayer under Normal and Tangential Loading

by Adam Stanisław Bajkowski, Rafał Grądzki, Justinas Gargasas and Kristina Bazienė

Materials 2022, 15(24), 9020; https://doi.org/10.3390/ma15249020 - 16 Dec 2022

Viewed by 1055

Abstract

In this paper, we obtained the analytic solution of the three-dimensional problem of elasticity concerning non-homogeneous half-space, in which the surface is under normal and tangential loading applied in a circular area. Half-space is composed of the homogeneous body, as well as coatings [...] Read more.

In this paper, we obtained the analytic solution of the three-dimensional problem of elasticity concerning non-homogeneous half-space, in which the surface is under normal and tangential loading applied in a circular area. Half-space is composed of the homogeneous body, as well as coatings containing two homogeneous layers: interlayer and top layer. The analysis was carried out in cases where the Young’s modulus of the intermediate layer differed from the Young’s modulus of the substrate and the top layer. We have concentrated on first principal stress analysis. The obtained results can serve as an indication for the design of the composition of coatings in the context of tensile stress. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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20 pages, 7469 KiB

Open AccessArticle

Numerical Analysis of Dynamic Properties of an Auxetic Structure with Rotating Squares with Holes

by Agata Mrozek and Tomasz Strek

Materials 2022, 15(24), 8712; https://doi.org/10.3390/ma15248712 - 07 Dec 2022

Cited by 14 | Viewed by 2093

Abstract

In this paper, a novel auxetic structure with rotating squares with holes is investigated. The unit cell of the structure consists of four units in the shape of a square with cut corners and holes. Finally, the structure represents a kind of modified [...] Read more.

In this paper, a novel auxetic structure with rotating squares with holes is investigated. The unit cell of the structure consists of four units in the shape of a square with cut corners and holes. Finally, the structure represents a kind of modified auxetic structure made of rotating squares with holes or sheets of material with regularly arranged diamond and square cuts. Effective and dynamic properties of these structures depend on geometrical properties of the structure. The structures are characterized by an effective Poisson’s ratio from negative to positive values (from about minus one to about plus one). Numerical analysis is made for different geometrical features of the unit cells. The simulations enabled the determination of the dynamic characteristic of the analyzed structures using vibration transmission loss, transmissibility, and mechanical impedance. Numerical calculations were conducted using the finite element method. In the analyzed cases of cellular auxetic structures, a linear elasticity model of the material is assumed. The dynamic characteristic of modified rotating square structures is strongly dependent not only on frequency. The dynamic behavior could also be enhanced by adjusting the geometric parameter of the structure. Auxetic and non-auxetic structures show different static and dynamic properties. The dynamic properties of the analyzed structures were examined in order to determine the frequency ranges of dynamic loads for which the values of mechanical impedance and transmissibility are appropriate. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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13 pages, 3811 KiB

Open AccessArticle

Study on the Deposition Uniformity of Triple-Target Magnetron Co-Sputtering System: Numerical Simulation and Experiment

by Guo Zhu, Baijun Xiao, Ganxin Chen and Zhiyin Gan

Materials 2022, 15(21), 7770; https://doi.org/10.3390/ma15217770 - 04 Nov 2022

Cited by 2 | Viewed by 1503

Abstract

The uniformity of magnetron-sputtered films can be evaluated using an analytical model whose key parameters, such as included angle cosine and distance between infinitesimal elements, are so far calculated based on targets-substrate geometric relation. This existing computation scheme is not applicable in a [...] Read more.

The uniformity of magnetron-sputtered films can be evaluated using an analytical model whose key parameters, such as included angle cosine and distance between infinitesimal elements, are so far calculated based on targets-substrate geometric relation. This existing computation scheme is not applicable in a triple-target magnetron co-sputtering system with complex targets-substrate geometric relation. In this work, a computation method was proposed to calculate the deposition uniformity of a triple-target magnetron co-sputtering system based on the analytical model. In this method, the coordinates of the infinitesimal elements on the substrate and targets were calibrated in an identical global coordinate system via coordinate transformation, such that the key parameters of the analytical formula can be evaluated by vector computation. The effects of the target-substrate angle and target-substrate distance on the deposition uniformity of a given triple-target magnetron co-sputtering system were investigated via numerical simulation and experiment, respectively. Simulation results were consistent with experimental results. Relevant evolution mechanisms of the deposition uniformity of the co-sputtering system with the variations of target-substrate parameters were discussed in detail based on the simulation results. It is expected that this computation approach can be employed to provide theoretical guidance for the fast and economical fabrication of high-quality, large-area film and composite films. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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17 pages, 846 KiB

Open AccessArticle

Fractional Order Dual-Phase-Lag Model of Heat Conduction in a Composite Spherical Medium

by Stanisław Kukla, Urszula Siedlecka and Mariusz Ciesielski

Materials 2022, 15(20), 7251; https://doi.org/10.3390/ma15207251 - 17 Oct 2022

Cited by 6 | Viewed by 1287

Abstract

In the paper, a solution of the fractional dual-phase-lag heat conduction problem is presented. The considerations are related to the heat conduction in a multi-layered spherical medium with azimuthal symmetry. The final form of the analytical solution is given in a form of [...] Read more.

In the paper, a solution of the fractional dual-phase-lag heat conduction problem is presented. The considerations are related to the heat conduction in a multi-layered spherical medium with azimuthal symmetry. The final form of the analytical solution is given in a form of the double series of spherical Bessel functions and Legendre functions. Numerical calculations concern the study of the effect of the order of the Caputo derivative on the temperature distribution in a composite solid sphere, hemisphere and spherical cone. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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27 pages, 14051 KiB

Open AccessEditor’s ChoiceArticle

Modified Micro-Mechanics Based Multiscale Model for Damage Analysis of Open-Hole Composite Laminates under Compression

by Meng Wang and Xiaochen Hang

Materials 2022, 15(15), 5105; https://doi.org/10.3390/ma15155105 - 22 Jul 2022

Cited by 2 | Viewed by 1641

Abstract

The multiscale model based on micro-mechanics failure theory is modified to consider complex internal structures, including a fiber random arrangement pattern and interface with the clustering method. Then, a feed-forward-neural-network (FFNN)-based damage evolution method is developed to evaluate the macroscale property degradation. The [...] Read more.

The multiscale model based on micro-mechanics failure theory is modified to consider complex internal structures, including a fiber random arrangement pattern and interface with the clustering method. Then, a feed-forward-neural-network (FFNN)-based damage evolution method is developed to evaluate the macroscale property degradation. The progressive damage analysis of open-hole laminates under compression is conducted to validate the modified multiscale method. The predicted results reveal that the interface results in the premature initiation of damage, and the fiber random arrangement pattern contributes to the decrease in the predicted compression responses. The developed FFNN-based method aimed at degradation results in an increase in the predicted compression strength. For the fiber random distribution pattern, the increase in percentage of predicted compressive strength is 6.0%, which is much larger than the value for the fiber diamond distribution pattern. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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17 pages, 6886 KiB

Open AccessArticle

Methodology of Leakage Prediction in Gasketed Flange Joints at Pipeline Deformations

by Przemysław Jaszak, Janusz Skrzypacz, Andrzej Borawski and Rafał Grzejda

Materials 2022, 15(12), 4354; https://doi.org/10.3390/ma15124354 - 20 Jun 2022

Cited by 10 | Viewed by 1986

Abstract

The paper presents the proposal of a leakage prediction method in flange joints, after pipeline deformation, based on FEM (Finite Element Methods). The stages of developing the design are discussed, and a complex, multi-stage method of applying the loads is presented in detail. [...] Read more.

The paper presents the proposal of a leakage prediction method in flange joints, after pipeline deformation, based on FEM (Finite Element Methods). The stages of developing the design are discussed, and a complex, multi-stage method of applying the loads is presented in detail. Moreover, the gasket material data obtained in experiments were used. The paper also presents the results of calculations on a non-uniform stress distribution in the radial direction of the gasket. In addition, it has been shown that the deflection of the pipeline with a minor displacement causes an increase in the diversification of the circumferential pressure of the gasket, and also has a significant influence on the determination of the actual state of stress to which the gasket is subject. Moreover, it was found that the distribution of contact pressure on the deflection of the pipeline has a significant influence on the level of leakage. The results of tests are compared to the results of the numerical calculations of the stress in bolts. By comparing the bolt tension changes obtained by numerical and experiment analyses, it has been shown that the assumptions made in developing the numerical model are correct. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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16 pages, 6362 KiB

Open AccessArticle

Comparative Numerical Studies on the Structural Behavior of Buried Pipes Subjected to Extreme Environmental Actions

by Ana Diana Ancaș, Florin-Emilian Țurcanu, Marina Verdeș, Sebastian Valeriu Hudisteanu, Nelu-Cristian Cherecheș, Cătălin-George Popovici and Mihai Profire

Materials 2022, 15(9), 3385; https://doi.org/10.3390/ma15093385 - 09 May 2022

Cited by 1 | Viewed by 1439

Abstract

Globally, there are several critical infrastructure networks (water and gas networks) whose disruption or destruction would significantly affect the maintenance of vital societal functions, such as the health, safety, security, and social or economic well-being of people. They would also have significant local, [...] Read more.

Globally, there are several critical infrastructure networks (water and gas networks) whose disruption or destruction would significantly affect the maintenance of vital societal functions, such as the health, safety, security, and social or economic well-being of people. They would also have significant local, regional, and national impacts as a result of the inability to maintain those functions, and would have similar cross-border effects. The main objective of this article is to investigate by comparative numerical studies the structural response of three types of buried pipes made of different materials, primarily steel, concrete, and high-density polyethylene, resulting from the impact of the environment through exceptional external actions, such as explosions at the surface of the land in the vicinity of the laying areas. The dynamic transient analysis of the equation of motion with the application of the explicit integration procedure was performed with the ANSYS numerical simulation program. This study allows designers to solve complex problems related to the quality of the laying ground of water networks to canals. The knowledge accumulated gives us the possibility to correctly specify the optimal economic and technical value of the ratio between the laying depth of pipes and their diameter, the importance of the radius ratio of the pipe and the thickness of its wall, and, importantly, the improvement of the quality of the foundation ground. Following the results obtained, it is estimated that the optimal economic and technical value of the ratio between the laying depth of the pipes (H) and their diameter (D) is 3, regardless of the material from which the pipe is made. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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21 pages, 5108 KiB

Open AccessArticle

Parametric Optimization of Thin-Walled 3D Beams with Perforation Based on Homogenization and Soft Computing

by Tomasz Gajewski, Natalia Staszak and Tomasz Garbowski

Materials 2022, 15(7), 2520; https://doi.org/10.3390/ma15072520 - 29 Mar 2022

Cited by 7 | Viewed by 1826

Abstract

The production of thin-walled beams with various cross-sections is increasingly automated and digitized. This allows producing complicated cross-section shapes with a very high precision. Thus, a new opportunity has appeared to optimize these types of products. The optimized parameters are not only the [...] Read more.

The production of thin-walled beams with various cross-sections is increasingly automated and digitized. This allows producing complicated cross-section shapes with a very high precision. Thus, a new opportunity has appeared to optimize these types of products. The optimized parameters are not only the lengths of the individual sections of the cross section, but also the bending angles and openings along the beam length. The simultaneous maximization of the compressive, bending and shear stiffness as well as the minimization of the production cost or the weight of the element makes the problem a multi-criteria issue. The paper proposes a complete procedure for optimizing various open sections of thin-walled beam with different openings along its length. The procedure is based on the developed algorithms for traditional and soft computing optimization as well as the original numerical homogenization method. Although the work uses the finite element method (FEM), no computational stress analyses are required, i.e., solving the system of equations, except for building a full stiffness matrix of the optimized element. The shell-to-beam homogenization procedure used is based on equivalence strain energy between the full 3D representative volume element (RVE) and its beam representation. The proposed procedure allows for quick optimization of any open sections of thin-walled beams in a few simple steps. The procedure can be easily implemented in any development environment, for instance in MATLAB, as it was done in this paper. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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15 pages, 3948 KiB

Open AccessArticle

Shell-to-Beam Numerical Homogenization of 3D Thin-Walled Perforated Beams

by Natalia Staszak, Tomasz Gajewski and Tomasz Garbowski

Materials 2022, 15(5), 1827; https://doi.org/10.3390/ma15051827 - 28 Feb 2022

Cited by 12 | Viewed by 1664

Abstract

Determining the geometric characteristics of even complex cross-sections of steel beams is not a major challenge nowadays. The problem arises when openings of various shapes and sizes appear at more or less regular intervals along the length of the beam. Such alternations cause [...] Read more.

Determining the geometric characteristics of even complex cross-sections of steel beams is not a major challenge nowadays. The problem arises when openings of various shapes and sizes appear at more or less regular intervals along the length of the beam. Such alternations cause the beam to have different stiffnesses along its length. It has different bending and shear stiffnesses at the opening point and in the full section. In this paper, we present a very convenient and easy-to-implement method of determining the equivalent stiffness of a beam with any cross-section (open or closed) and with any system of holes along its length. The presented method uses the principles of the finite element method (FEM), but does not require any formal analysis, i.e., solving the system of equations. All that is needed is a global stiffness matrix of the representative volumetric element (RVE) of the 3D representation of a beam modeled with shell finite elements. The proposed shell-to-beam homogenization procedure is based on the strain energy equivalence, and allows for precise and quick determination of all equivalent stiffnesses of a beam (flexural and shear). The results of the numerical homogenization procedure were compared with the existing analytical solution and experimental results of various sections. It has been shown that the results obtained are comparable with the reference results. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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21 pages, 3385 KiB

Open AccessArticle

Study of Rolling Motion of Ships in Random Beam Seas with Nonlinear Restoring Moment and Damping Effects Using Neuroevolutionary Technique

by Naveed Ahmad Khan, Muhammad Sulaiman, Carlos Andrés Tavera Romero, Ghaylen Laouini and Fahad Sameer Alshammari

Materials 2022, 15(2), 674; https://doi.org/10.3390/ma15020674 - 17 Jan 2022

Cited by 13 | Viewed by 2558

Abstract

In this paper, a mathematical model for the rolling motion of ships in random beam seas has been investigated. The ships’ steady-state rolling motion with a nonlinear restoring moment and damping effect is modeled by the nonlinear second-order differential equation. Furthermore, an artificial [...] Read more.

In this paper, a mathematical model for the rolling motion of ships in random beam seas has been investigated. The ships’ steady-state rolling motion with a nonlinear restoring moment and damping effect is modeled by the nonlinear second-order differential equation. Furthermore, an artificial neural network (NN)-based, backpropagated Levenberg-Marquardt (LM) algorithm is utilized to interpret a numerical solution for the roll angle

(x (t))

, velocity

(x^{'} (t))

, and acceleration

(x^{''} (t))

of the ship in random beam seas. A reference data set based on numerical examples of the mathematical model for a rolling ship for the LM-NN algorithm is generated by the numerical solver Runge–Kutta method of order 4 (RK-4). The LM-NN algorithm further uses the created data set for the validation, testing, and training of approximate solutions. The outcomes of the design paradigm are compared with those of the homotopy perturbation method (HPM), optimal homotopy analysis method (OHAM), and RK-4. Statistical analyses of the mean square error (MSE), regression, error histograms, proportional performance, and computational complexity further validate the worth of the LM-NN algorithm. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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17 pages, 4863 KiB

Open AccessArticle

Analytical Determination of the Bending Stiffness of a Five-Layer Corrugated Cardboard with Imperfections

by Tomasz Garbowski and Anna Knitter-Piątkowska

Materials 2022, 15(2), 663; https://doi.org/10.3390/ma15020663 - 16 Jan 2022

Cited by 18 | Viewed by 2634

Abstract

Bending stiffness (BS) is one of the two most important mechanical parameters of corrugated board. The second is edge crush resistance (ECT). Both are used in many analytical formulas to assess the load capacity of corrugated cardboard packaging. Therefore, the correct determination of [...] Read more.

Bending stiffness (BS) is one of the two most important mechanical parameters of corrugated board. The second is edge crush resistance (ECT). Both are used in many analytical formulas to assess the load capacity of corrugated cardboard packaging. Therefore, the correct determination of bending stiffness is crucial in the design of corrugated board structures. This paper focuses on the analytical determination of BS based on the known parameters of the constituent papers and the geometry of the corrugated layers. The work analyzes in detail the dependence of the bending stiffness of an asymmetric, five-layer corrugated cardboard on the sample arrangement. A specimen bent so that the layers on the lower wave side are compressed has approximately 10% higher stiffness value. This is due to imperfections, which are particularly important in the case of compression of very thin liners. The study showed that imperfection at the level of a few microns causes noticeable drops in bending stiffness. The method has also been validated by means of experimental data from the literature and simple numerical finite element model (FEM). The obtained compliance of the computational model with the experimental model is very satisfactory. The work also included a critical discussion of the already published data and observations of other scientists in the field. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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26 pages, 1790 KiB

Open AccessArticle

An Optimistic Solver for the Mathematical Model of the Flow of Johnson Segalman Fluid on the Surface of an Infinitely Long Vertical Cylinder

by Naveed Ahmad Khan, Fahad Sameer Alshammari, Carlos Andrés Tavera Romero, Muhammad Sulaiman and Seyedali Mirjalili

Materials 2021, 14(24), 7798; https://doi.org/10.3390/ma14247798 - 16 Dec 2021

Cited by 12 | Viewed by 2212

Abstract

In this paper, a novel soft computing technique is designed to analyze the mathematical model of the steady thin film flow of Johnson–Segalman fluid on the surface of an infinitely long vertical cylinder used in the drainage system by using artificial neural networks [...] Read more.

In this paper, a novel soft computing technique is designed to analyze the mathematical model of the steady thin film flow of Johnson–Segalman fluid on the surface of an infinitely long vertical cylinder used in the drainage system by using artificial neural networks (ANNs). The approximate series solutions are constructed by Legendre polynomials and a Legendre polynomial-based artificial neural networks architecture (LNN) to approximate solutions for drainage problems. The training of designed neurons in an LNN structure is carried out by a hybridizing generalized normal distribution optimization (GNDO) algorithm and sequential quadratic programming (SQP). To investigate the capabilities of the proposed LNN-GNDO-SQP algorithm, the effect of variations in various non-Newtonian parameters like Stokes number (

S_{t}

), Weissenberg number (

W_{e}

), slip parameters (a), and the ratio of viscosities (

ϕ

) on velocity profiles of the of steady thin film flow of non-Newtonian Johnson–Segalman fluid are investigated. The results establish that the velocity profile is directly affected by increasing Stokes and Weissenberg numbers while the ratio of viscosities and slip parameter inversely affects the fluid’s velocity profile. To validate the proposed technique’s efficiency, solutions and absolute errors are compared with reference solutions calculated by RK-4 (ode45) and the Genetic algorithm-Active set algorithm (GA-ASA). To study the stability, efficiency and accuracy of the LNN-GNDO-SQP algorithm, extensive graphical and statistical analyses are conducted based on absolute errors, mean, median, standard deviation, mean absolute deviation, Theil’s inequality coefficient (TIC), and error in Nash Sutcliffe efficiency (ENSE). Statistics of the performance indicators are approaching zero, which dictates the proposed algorithm’s worth and reliability. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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28 pages, 6617 KiB

Open AccessArticle

The Isotropic Material Design of In-Plane Loaded Elasto-Plastic Plates

by Sławomir Czarnecki and Tomasz Lewiński

Materials 2021, 14(23), 7430; https://doi.org/10.3390/ma14237430 - 03 Dec 2021

Cited by 2 | Viewed by 1554

Abstract

This paper puts forward a new version of the Isotropic Material Design method for the optimum design of structures made of an elasto-plastic material within the Hencky-Nadai-Ilyushin theory. This method provides the optimal layouts of the moduli of isotropy to make the overall [...] Read more.

This paper puts forward a new version of the Isotropic Material Design method for the optimum design of structures made of an elasto-plastic material within the Hencky-Nadai-Ilyushin theory. This method provides the optimal layouts of the moduli of isotropy to make the overall compliance minimal. Thus, the bulk and shear moduli are the only design variables, both assumed as non-negative fields. The trace of the Hooke tensor represents the unit cost of the design. The yield condition is assumed to be independent of the design variables, to make the design process as simple as possible. By eliminating the design variables, the optimum design problem is reduced to the pair of the two mutually dual Linear Constrained Problems (LCP). The solution to the LCP stress-based problem directly determines the layout of the optimal moduli. A numerical method has been developed to construct approximate solutions, which paves the way for constructing the final layouts of the elastic moduli. Selected illustrative solutions are reported, corresponding to various data concerning the yield limit and the cost of the design. The yield condition introduced in this paper results in bounding the values of the optimal moduli in the places of possible stress concentration, such as reentrant corners. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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18 pages, 4262 KiB

Open AccessArticle

A Finite Difference Algorithm Applied to the Averaged Equations of the Heat Conduction Issue in Biperiodic Composites—Robin Boundary Conditions

by Ewelina Kubacka and Piotr Ostrowski

Materials 2021, 14(21), 6329; https://doi.org/10.3390/ma14216329 - 23 Oct 2021

Cited by 3 | Viewed by 1265

Abstract

This note deals with the heat conduction issue in biperiodic composites made of two different materials. To consider such a nonuniform structure, the equations describing the behavior of the composite under thermal (Robin) boundary conditions were averaged by using tolerance modelling. In this [...] Read more.

This note deals with the heat conduction issue in biperiodic composites made of two different materials. To consider such a nonuniform structure, the equations describing the behavior of the composite under thermal (Robin) boundary conditions were averaged by using tolerance modelling. In this note, the process of creating an algorithm that uses the finite difference method to deal with averaged model equations is shown. This algorithm can be used to solve these equations and find out the temperature field distribution of a biperiodic composite. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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15 pages, 3963 KiB

Open AccessArticle

Numerical Study of Heat and Mass Transfer during Cryopreservation Process with Application of Directed Interval Arithmetic

by Alicja Piasecka-Belkhayat and Anna Skorupa

Materials 2021, 14(11), 2966; https://doi.org/10.3390/ma14112966 - 31 May 2021

Cited by 3 | Viewed by 2078

Abstract

In the present paper, numerical modelling of heat and mass transfer proceeding in a two-dimensional axially symmetrical articular cartilage sample subjected to a cryopreservation process is presented. In the model under consideration, interval parameters were assumed. The heat transfer process is described using [...] Read more.

In the present paper, numerical modelling of heat and mass transfer proceeding in a two-dimensional axially symmetrical articular cartilage sample subjected to a cryopreservation process is presented. In the model under consideration, interval parameters were assumed. The heat transfer process is described using the Fourier interval equation, while the cryoprotectant transport (DMSO) across the cell membrane is analyzed using a two-parameter model taking into account the simulation of the water volume in the chondrocytes and the change in DMSO concentration over time. The liquidus tracking (LT) protocol introduced by Pegg et al. was used to model the cryopreservation process. This procedure divides the heating and cooling phases into eight and seven steps, respectively, allowing precise regulation of temperature and cryoprotectant (CPA) concentration of bathing solutions. This protocol protects chondrocytes from ice crystal, osmotic stress, and electrolyte damage. The obtained interval concentrations of cryoprotectant in chondrocytes were compared with previous simulations obtained using the deterministic model and they are mostly in agreement with the simulation data. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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15 pages, 2562 KiB

Open AccessArticle

Modelling the Influence of Slide Burnishing Parameters on the Surface Roughness of Shafts Made of 42CrMo4 Heat-Treatable Steel

by Rafał Kluz, Katarzyna Antosz, Tomasz Trzepieciński and Magdalena Bucior

Materials 2021, 14(5), 1175; https://doi.org/10.3390/ma14051175 - 02 Mar 2021

Cited by 13 | Viewed by 1993

Abstract

This article presents the results of tests aimed at determining the effect of slide burnishing parameters on the surface roughness of shafts made of 42CrMo4 heat-treatable steel. The burnishing process was carried out using tools with polycrystalline diamond and cemented carbide tips. Before [...] Read more.

This article presents the results of tests aimed at determining the effect of slide burnishing parameters on the surface roughness of shafts made of 42CrMo4 heat-treatable steel. The burnishing process was carried out using tools with polycrystalline diamond and cemented carbide tips. Before burnishing, the samples were turned on a turning lathe to produce samples with an average surface roughness Ra = 2.6 µm. The investigations were carried out according to three-leveled Hartley’s poly selective quasi D (PS/DS-P: Ha3) plan, which enables a regression equation in the form of a second-order polynomial to be defined. Artificial neural network models were also used to predict the roughness of the surface of the shafts after slide burnishing. The input parameters of the process that were taken into account included the values of pressure, burnishing speed and feed rate. Overall, the burnishing process examined leads to a reduction in the value of the surface roughness described by the Ra parameter. The artificial neural networks with the best regression statistics predicted an average surface roughness of the shafts with R² = 0.987. The lowest root-mean-square error and mean absolute error were obtained with all the network structures analysed that were trained with the quasi Newton algorithm. Full article

(This article belongs to the Special Issue Analytical and Computational Methods in Material and Mechanical Engineering)

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