scholarly journals Assessment of the reinforcing ability of a composite bandage for modern pipeline repair systems

2021 ◽  
Author(s):  
Eugen Savchuk ◽  
Viktor Rubashevskyi ◽  
Sergiy Shukayev
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Comparative Analysis ◽  
Service Life ◽  
Close Agreement ◽  
The Finite Element Method ◽  
Strain Ageing ◽  
Term Operation ◽  
Reinforced Steel

Abstract. The long-term operation of pipelines, which, in many cases, exceeds their regulatory service life, causes the strain ageing of metal, as well as the appearance of local mechano-corrosive damages. In this regard, the use of composites to reinforce worn pipelines constitutes one of today’s most promising technologies. In this study, a comparative analysis was performed between the composite-reinforced steel pipe calculations that were conducted using the finite element method (FEM), and those that were conducted in accordance with the DSTU ISO 24817:2019 standard. The FEM numerical calculations were carried out using the complete factorial experiment design (consisting of three factors at three levels, with twenty-seven calculations in total). Based on the results of these calculations, a regression model was developed to assess the circular deformation of the pipe’s outer surface depending on the thickness of the bandage, the thickness of the pipe, and the internal pressure. The FEM calculations were found to be in close agreement with analytical results.

scholarly journals COMPARATIVE ANALYSIS OF MONOCORTICAL AND BICORTICAL METHODS OF INSTALLING MINI-IMPLANTS

2021 ◽  
pp. 38-40
Author(s):  
O.Yu. Rivis ◽  
V.S. Melnyk ◽  
M.V. Rivis ◽  
K.V. Zombor
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Comparative Analysis ◽  
Cortical Bone ◽  
Bone Tissue ◽  
Orthodontic Treatment ◽  
The Finite Element Method ◽  
Force Load ◽  
Mini Implants ◽  
Element Method

The aim of the study. Carry out a comparative analysis of the support ability of human jaw bone tissue in monocortical and bicortical installation of a mini-implant of own design OMG. Research methods. In order to study biomechanical characteristics of developed OMG mini-implant and bone tissue capacity during monocortical and bicortical installation, the finite element method (MSE) was used. The scheme and finite element 2-D model of bicortical installation of OMG mini-implant (length 8 mm, diameter 1.8 mm) provided full penetration through one layer of cortical bone equal to 1 mm, the entire cancellous bone and immersion in the second layer of cortical bone by 0, 5 mm. No implantation was immersed in the second cortical layer of bone during monocortical installation. A single force load of 1 N was applied in the horizontal direction parallel to the cortical plate of the bone. Results of the study. One of the most important factors leading to the success of the use of a mini-implant is its stability in the process of orthodontic treatment. Quite a high level of failure in the monocortical installation of mini-screws has led to the search for better methods to ensure the stability of their use. This was a bicortical method of fixation, based on the placement of the minig screw in the thickness of the two cortical plates of the jaws. Area for such installation of mini-screws can be a site of a palate and alveolar sprouts at installation of miniimplants through all its thickness. As shown by our data on the use of the finite element method under the force load of the biomechanical system "bone - mini-implant", the stress concentration zone is located in the area of the cortical bone of the jaw. The results of the calculation of the maximum stresses (σmax, MPa) and the maximum possible displacements (umax, mm) of the mini-implant in the biomechanical system "bone - mini-implant" in monocortical installation were, respectively, 8.27 MPa and 0.300 * 10-8 mm and in bicortical installation 6.00 MPa and 0.201 * 10-8 mm. The bicortical method of fixing the mini-implant in the jaw bones significantly increases the ability to resist deformation of this type of biomechanical system under force loads of the mini-implant. In the bicortical method of mini-implant placement, the extreme values of equivalent according to Mises stresses in the upper part of the cortical bone of the jaw are reduced by 27%. This can be explained by a significant increase in the area of contact due to the two layers of the cortical bone of the jaw with the surface of the mini-implant. Conclusion. The bicortical method of installing mini-implants is a more effective and reliable way to provide skeletal support during orthodontic treatment.

scholarly journals Comparative Analysis of Parallel Hybrid Magnet Memory Machines with Different PM Arrangements

2021 ◽  
Vol 12 (4) ◽  
pp. 177
Author(s):  
Yixian Wang ◽  
Hui Yang ◽  
Hao Zheng ◽  
Heyun Lin ◽  
Shukang Lyu
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Comparative Analysis ◽  
Permanent Magnet ◽  
Magnetic Circuit ◽  
The Finite Element Method ◽  
Hybrid Magnet ◽  
Parallel Hybrid ◽  
Electromagnetic Characteristics ◽  
Magnetic Barriers

This paper presents a comparative analysis of two parallel hybrid magnet memory machines (PHMMMs) with different permanent magnet (PM) arrangements. The proposed machines are both geometrically characterized by a parallel U-shaped hybrid PM configuration and several q-axis magnetic barriers. The configurations and operating principles of the investigated machines are introduced firstly. The effect of magnet arrangements on the performance of the proposed machines is then evaluated with a simplified magnetic circuit model. Furthermore, the electromagnetic characteristics of the proposed machines are investigated and compared by the finite-element method (FEM). The experiments on one prototype are carried out to validate the FEM results.

scholarly journals Modeling and research of the process of preparing the surface of a part for thermal spray coating

2020 ◽  
Vol 329 ◽  
pp. 03052
Author(s):  
Aleksandr Novikov ◽  
Aleksei Rodishev ◽  
Andrei Gorin ◽  
Maria Tokmakova
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Comparative Analysis ◽  
Field Experiment ◽  
Adhesive Strength ◽  
Spray Coating ◽  
Thermal Spray Coating ◽  
The Finite Element Method ◽  
Antifriction Coating ◽  
Rolling Method

The article presents an analysis of ways to increase the adhesive strength of antifriction coating. A rational method for the mechanical formation of surfaces is proposed. The calculation of the workpiece based on the finite element method has been carried out. The theoretical dependences of metal lifting on the depth of the rolling roller are obtained. The results of a field experiment are presented. A comparative analysis of theoretical and practical results of the research has been carried out. Recommendations are given for the further use of the net rolling method with a pre-cut “ragged thread”.

Development of a Compact Deformable Mirror Using Push-Pull Actuators

2014 ◽  
Vol 613 ◽  
pp. 200-203
Author(s):  
Hiroki Shimizu ◽  
Keitaro Tanaka ◽  
Yuuma Tamaru
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Piezoelectric Actuators ◽  
Practical Method ◽  
Simulation Method ◽  
Deformable Mirror ◽  
The Finite Element Method ◽  
Convex Shape ◽  
Long Term Stability

A small deformable mirror which realizes concave shape as well as convex shape has been developed. In addition, this deformable mirror was developed to realize long term stability. For this purpose, a new push-pull actuator using two multilayered piezoelectric actuators aligned inline was designed. In this process, a practical method for simulating the property of piezoelectric actuator in the finite element method was proposed. From the experimental results, it was confirmed that newly developed deformable mirror has the ability to make complex profiles. Furthermore, efficiency of proposed simulation method was also confirmed.

scholarly journals Ultrasonic Sensors Enabling Early Detection of Emergency Trends and Analysis of Structure Inclination and Stability by Means of Highly Accurate Level Measurements

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1789
Author(s):  
Leszek Ornoch ◽  
Paweł Popielski ◽  
Andrzej Olszewski ◽  
Adam Kasprzak
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Early Detection ◽  
Water Levels ◽  
The Finite Element Method ◽  
Ultrasonic Sensors ◽  
Temperature Changes ◽  
New Models ◽  
Object Behavior

Building inclinations can be measured through the use of ultrasonic hydrostatic levelers. These are used to measure long-term relative displacements of vertical parts of structures and utilize the principle of communicating vessels (similar to the classic water scales). The presented ultrasonic displacement measurement technique was developed by Ultrasystem in the 1990s and was applied to several objects in Poland. Long-term measurements enabled the development of a model of object behavior under the influence of various factors. Among these are the annual cycle of temperature changes, fluctuating water levels, turbine chamber emptying, etc. Such a model can facilitate the prediction of failure based on the appearance of changes deviating from typical behavior (e.g., a much stronger dependence of the inclination as a function of the water level). The results obtained with the help of ultrasonic sensors enable the observation of subtle deformations of the object, which is valuable when developing and calibrating new models of the object (e.g., by means of the finite element method).

scholarly journals Composite beams with indented construction joint – comparison of results of laboratory tests and numerical analysis

2020 ◽  
Vol 19 (4) ◽  
pp. 031-042
Author(s):  
Grzegorz Sadowski ◽  
Piotr Wiliński ◽  
Anna Halicka
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Comparative Analysis ◽  
Composite Beam ◽  
Laboratory Tests ◽  
Virtual Model ◽  
Test Results ◽  
Shear Cracks ◽  
The Finite Element Method ◽  
Laboratory Test Results

The paper presents a comparative analysis of the behaviour of a composite beam, consisted of a precast element with indented surface and new concrete layer, subjected to 4-point bending. The results obtained from the virtual model of the beam created using the finite element method (Abaqus/CEA 2019 software) were compared with the laboratory test results obtained with use of the digital image correlation (DIC) method for identifying the crack pattern. The virtual model of composite beam was calibrated by the choice of interface parameters ensuring that the value of load resulting in delamination between concrete layers was close to that value obtained in the laboratory tests. The comparative analysis showed that the pattern of bending and shear cracks and the pattern of interface crack obtained with the finite element method reflect the laboratory test results properly. It can be assumed that the crack between concrete layers is related to the appearance and propagation of shear cracks. On the basis of FEM analysis it can be concluded that the phenomena identified as “shear friction” and “dowel action” are significantly activated after the interface cracking.

COMPARATIVE ANALYSIS OF THE SYSTEM APM WINMACHINE AND CAE ABAQUS FOR CALCULATING THE STRENGTH OF A WELDED JOINT

2020 ◽  
Vol 5 ◽  
pp. 28-32
Author(s):  
V.V. LEONTYEV ◽  
E.V. KONDRATOVA ◽  
V.P. KOLOMIYCHENKO
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Comparative Analysis ◽  
Strain State ◽  
Safety Margin ◽  
Operating Conditions ◽  
The Finite Element Method ◽  
Stress Strain ◽  
Stress Strain State ◽  
Element Method

Traditional methods for calculating welded joints are based on approximate methods for determining the forces that occur in the joint. This leads to inaccuracies in the definition of stress. In addition, this approach does not allow obtaining a complete picture of the stress-strain state of the joint. All this leads to the need to increase the coefficient of safety margin and, as a result, to increase the cost of construction. The proposed method of calculating the connection using the finite element method allows us to determine the stresses in all the elements of the connection very accurately. This makes it possible to obtain a reliable picture of the stress-strain state of all elements of the connection. As a result, it is possible to reduce the complexity of creating a compound and its mass. The finite element method should be used for calculating critical connections with complex operating conditions. An example of calculating such a connection is considered. A comparative analysis of the results of calculating the t-joint using the arm Joint module Of the WinMachine arm system and the Abaqus finite element package is performed.

Sign in / Sign up

Export Citation Format

Share Document