scholarly journals Analyzing calculation results of non-stationary axisymmetric thermoelasticity task for a circular isotropic plate

2018 ◽  
Vol 196 ◽  
pp. 01007
Author(s):  
Dmitriy Shlyahin
Keyword(s):  
Temperature Change ◽  
High Speed ◽  
Isotropic Plate ◽  
Integral Transformation ◽  
Adjoint System ◽  
Thin Plates ◽  
Movement Vector ◽  
Calculation Results ◽  
Finite Integral ◽  
Separation Of Variable

The paper releases results of numerical calculation of axisymmetric dynamic thermoelasticity task for a fixed circular isotropic plate in case of temperature change on its front faces (boundary conditions of the 1st type). The calculated ratios are obtained by using the GL-theory of thermoelasticity (classical theory), which determines the dependence of the vector of heat flux on the velocity of change and temperature gradient. The mathematical model of the task in question includes differential equations of axisymmetric motion and thermal conductivity, formulated as regard to the component of the movement vector and the function of temperature change. Not self-adjoint system is investigated independently. For its solution, a mathematical apparatus technique of separation of variable in the form of finite integral transformations is used, that is transformations of Fourier, Hankel and generalized integral transformation (GIT). The constructed calculation ratios give an opportunity to define stress and strain state and character of distribution of a thermal field of rigidly fixed circular plate with arbitrary axially symmetrical temperature external influence. It is shown, that elastic inertial characteristics of a plate influence the law of change of movement over time only while investigating very thin plates at high-speed temperature impact.

New Analytical Solutions of Buckling Problem of Rotationally-Restrained Rectangular Thin Plates

2019 ◽  
Vol 11 (10) ◽  
pp. 1950101 ◽  
Author(s):  
Salamat Ullah ◽  
Jinghui Zhang ◽  
Yang Zhong
Keyword(s):  
Boundary Conditions ◽  
Integral Transform ◽  
Integral Transformation ◽  
Solution Procedure ◽  
Thin Plates ◽  
Algebraic Equations ◽  
Transform Method ◽  
Linear Algebraic Equations ◽  
Title Problem ◽  
Finite Integral

A double finite sine integral transform method is employed to analyze the buckling problem of rectangular thin plate with rotationally-restrained boundary condition. The method provides more reasonable and theoretical procedure than conventional inverse/semi-inverse methods through eliminating the need to preselect the deflection function. Unlike the methods based on Fourier series, the finite integral transform directly solves the governing equation, which automatically involves the boundary conditions. In the solution procedure, after performing integral transformation the title problem is converted to solve a fully regular infinite system of linear algebraic equations with the unknowns determined by satisfying associated boundary conditions. Then, through some mathematical manipulation the analytical buckling solution is elegantly achieved in a straightforward procedure. Various edge flexibilities are investigated through selecting the rotational fixity factor, including simply supported and clamped edges as limiting situations. Finally, comprehensive analytical results obtained in this paper illuminate the validity of the proposed method by comparing with the existing literature as well as the finite element method using (ABAQUS) software.

Dynamic Analysis of DVG 850 High-Speed Machining Center

2012 ◽  
Vol 487 ◽  
pp. 203-207
Author(s):  
Gong Xue Zhang ◽  
Xiao Kai Shen
Keyword(s):  
High Speed ◽  
Simulation Analysis ◽  
Response Analysis ◽  
Improved Method ◽  
Analysis Software ◽  
Element Analysis ◽  
Harmonic Response ◽  
Machining Center ◽  
Calculation Results ◽  
Harmonic Response Analysis

Purpose, with the application of workbench finite element analysis software, get the analysis results of DVG 850 high-speed vertical machining center via the modal analysis and harmonic response analysis. Use the calculation results for reference, put forward the improved method, and prove the credibility of the simulation analysis by testing DVG 850 prototype.

High Speed Impact Behaviour of Thermo-Mechanically Processed AA 6082-T6 Thin Plates

2018 ◽  
Vol 5 (9) ◽  
pp. 17203-17212 ◽  
Author(s):  
Rahul Dubey ◽  
Srinivasa Rakesh ◽  
R Velmurugan ◽  
R Jayaganthan
Keyword(s):  
High Speed ◽  
Thin Plates ◽  
Impact Behaviour ◽  
High Speed Impact

scholarly journals A Novel Approach on the Unipolar Axial Type Eddy Current Brake Model Considering the Skin Effect

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1561
Author(s):  
Hery Tri Waloyo ◽  
U Ubaidillah ◽  
Dominicus Danardono Dwi Prija Tjahjana ◽  
Muhammad Nizam ◽  
Muhammad Aziz
Keyword(s):  
Correction Factor ◽  
Eddy Current ◽  
High Speed ◽  
Skin Effect ◽  
Actual Condition ◽  
Average Error ◽  
Low Speed ◽  
Novel Approach ◽  
Calculation Results ◽  
Braking Torque

The braking torque mathematical modelling in electromagnetic eddy current brake (ECB) often ignores the skin effect that occurrs during operation. However this phenomenon can not be simply neglected. Therefore, this paper presents a mathematical model of braking torque for a unipolar axial type of ECB system with a non-magnetic disk, which considers the skin effects. The use of mathematical models that consider the existence of skin effects is significant in approaching the braking torque according to the actual condition. The utilization of generic calculations to the model of the ECB braking torque leads to invalid results. Hence, in this paper, the correction factor was added to improve the braking torque calculation as a comparator to the proposed equation. However, the modification and addition of the correction factor were only valid to estimate the low-speed regimes of torque, but very distant for the high-speed condition. From the comparison of calculated values using analytical and 3D modelling, the amount of braking torque at a low speed was found to have an average error for the equation using a correction factor of 1.78 Nm, while after repairing, a value of 1.16 Nm was obtained. For the overall speed, an average error of 14.63 Nm was achieved, while the proposed equation had a small difference of 1.79 Nm. The torque difference from the calculation results of the proposed model with the measurement value in the experiment was 4.9%. Therefore, it can be concluded that the proposed equation provided a better braking torque value approach for both low and high speeds.

Study on Lightweight of the Engine Piston Based on Topology Optimization

2011 ◽  
Vol 201-203 ◽  
pp. 1308-1311 ◽  
Author(s):  
Fa Rong Du ◽  
Zhi Tao
Keyword(s):  
Topology Optimization ◽  
High Speed ◽  
Gasoline Engine ◽  
Optimization Method ◽  
Variable Density ◽  
Complex Stress ◽  
Density Topology ◽  
Before And After ◽  
Calculation Results ◽  
Hyper Works

The topology optimization and analysis were studied on the area of piston pin boss for a high-speed gasoline engine based on the variable density topology optimization method. Firstly, the model of the variable density topology optimization was founded. Then, the topology optimization and topology deconstruction on the piston pin boss were carried out by using Hyper Works. In this process, the minimum mass of piston was pursued as an objective function and the displacements of specified nodes on the piston skirt were made as constraints. Based on the topology optimization, the piston configuration of curved rod frame was designed. The complex stress of the piston before and after optimization was calculated respectively by ANSYS. The calculation results indicate that the piston mass can be lightened by 30% through optimizing under the same level of maximal stress, with satisfying the strength requirements. Therefore, the aim of piston lightweight is achieved, and there is no stress concentration in the area of the optimizing piston pin boss, which is propitious to the deformation compatibility of the piston pin boss.

Effect of Bond Layer on Bimaterial Assembly Subjected to Uniform Temperature Change

2011 ◽  
Vol 133 (4) ◽  
Author(s):  
D. Sujan ◽  
Dereje E. Woldemichael ◽  
M. V. V. Murthy ◽  
K. N. Seetharamu
Keyword(s):  
Temperature Change ◽  
Research Work ◽  
Interfacial Stress ◽  
Thin Plates ◽  
Rational Basis ◽  
Uniform Temperature ◽  
Stress Evaluation ◽  
Numerical Example ◽  
Bond Layer ◽  
Shear Compliance

When two thin plates or layers are bonded together, an extremely thin bond layer of third material exists between the two layers. This research work examines the effect of bond layer on the interfacial shearing and peeling stresses in a bimaterial model. Earlier papers on this topic are based on several mutually contradictory expressions for the shear compliance of the bond layer. This paper is aimed at resolving this ambiguity and presents derivation of shear compliance on a rational basis. A numerical example is carried out for a silicon-copper system with a gold-tin solder bond layer. The results obtained are likely to be useful in interfacial stress evaluation and physical design of bimaterial assemblies used in microelectronics and photonics applications.

Measurement Procedure of Ring Motion with the Use of Highspeed Camera During Electromagnetic Expansion

2012 ◽  
Vol 19 (4) ◽  
pp. 797-804 ◽  
Author(s):  
Jacek Janiszewski
Keyword(s):  
Experimental Data ◽  
Flow Stress ◽  
Plastic Flow ◽  
High Speed ◽  
Optical Measurement ◽  
Measurement Procedure ◽  
Expansion Process ◽  
Calculation Results ◽  
Plastic Flow Stress ◽  
Ring Material

Abstract An optical measurement method of radial displacement of a ring sample during its expansion with velocity of the order 172 m/s and estimation technique of plastic flow stress of a ring material on basis of the obtained experimental data are presented in the work. To measure the ring motion during the expansion process, the Phantom v12 digital high-speed camera was applied, whereas the specialized TEMA Automotive software was used to analyze the obtained movies. Application of the above-mentioned tools and the developed measuring procedure of the ring motion recording allowed to obtain reliable experimental data and calculation results of plastic flow stress of a copper ring with satisfactory accuracy.

Inverse Design of 3D Compressor Blades With Adjoint Method

2003 ◽  
Author(s):  
June Chung ◽  
Jeonghwan Shim ◽  
Ki D. Lee
Keyword(s):  
High Speed ◽  
Adjoint Method ◽  
Design Method ◽  
Computational Cost ◽  
Three Dimensional ◽  
Axial Compressor ◽  
Internal Flow ◽  
Adjoint System ◽  
Inverse Design ◽  
Compressor Blades

A three-dimensional (3D) CFD-based design method for high-speed axial compressor blades is being developed based on the discrete adjoint method. An adjoint code is built corresponding to RVC3D, a 3D turbomachinery Navier-Stokes analysis code developed at NASA Glenn. A validation study with the Euler equations indicates that the adjoint sensitivities are sensitive to the choice of boundary conditions for the adjoint variables in internal flow problems and constraints may be needed on internal boundaries to capture proper physics of the adjoint system. The design method is demonstrated with inverse design based on Euler physics, and the results indicate that the adjoint design method produces efficient 3D designs by drastically reducing the computational cost.

scholarly journals Research on Blade-Casing Rub-Impact Mechanism by Experiment and Simulation in Aeroengines

2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Jie Hong ◽  
Tianrang Li ◽  
Zhichao Liang ◽  
Dayi Zhang ◽  
Yanhong Ma
Keyword(s):  
High Speed ◽  
High Performance ◽  
Element Model ◽  
Physical Parameters ◽  
Test Rig ◽  
Calculation Results ◽  
Rotor Support ◽  
Blade Tip ◽  
Set Up ◽  
The Impact

Aeroengines pursue high performance, and compressing blade-casing clearance has become one of the main ways to improve turbomachinery efficiency. Rub-impact faults occur frequently with clearance decreasing. A high-speed rotor-support-casing test rig was set up, and the mechanism tests of light and heavy rub-impact were carried out. A finite element model of the test rig was established, and the calculation results were in good agreement with the experimental results under both kinds of rub-impact conditions. Based on the actual blade-casing structure model, the effects of the major physical parameters including imbalance and material characteristics were investigated. During the rub-impact, the highest stress occurs at the blade tip first and then it is transmitted to the blade root. Deformation on the impact blade tip generates easily with decreased yield strength, and stress concentration at the blade tip occurs obviously with weaker stiffness. The agreement of the computation results with the experimental data indicates the method could be used to estimate rub-impact characteristics and is effective in design and analyses process.

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