Journal of Applied and Computational Mechanics最新文献

Stress-based dimensional reduction and dual-mixed hp finite elements for elastic plates 弹性板的基于应力的尺寸缩减和双混合hp有限元

IF 3.1

Journal of Applied and Computational Mechanics Pub Date : 2023-01-01 DOI: 10.32973/jcam.2023.001

E. Bertóti

{"title":"Stress-based dimensional reduction and dual-mixed hp finite elements for elastic plates","authors":"E. Bertóti","doi":"10.32973/jcam.2023.001","DOIUrl":"https://doi.org/10.32973/jcam.2023.001","url":null,"abstract":"Starting from the linearized weak forms of the kinematic equation and the angular momentum balance equation of three-dimensional non-linear elasticity, a stressbased dimensional reduction procedure is presented for elastic plates. After expanding the three-dimensional non-symmetric stress tensor into power series with respect to the thickness coordinate, the translational equilibrium equations, written in terms of the expanded stress coefficients, are satisfied by introducing first-order stress functions. The symmetry of the stress field is satisfied in a weak sense by applying the material rotations as Lagrangian multipliers. The seven-field plate model developed in this way employs unmodified three-dimensional strain-stress relations. On the basis of the dimensionally reduced plate model derived, a new dual-mixed plate bending finite element model is developed and presented. The numerical performance of the hp-version plate elements is investigated through the solutions of standard plate bending problems. It is shown that the modeling error of the stress-based plate model in the energy norm is better than that of the displacement-based Kirchhoff- and Reissner-Mindlin plate models. The numerical solutions and their comparisons to reference solutions indicate that the dual-mixed hp elements are free from locking problems, in either the energy norm or the stress computations, both for h- and p-extensions, and the results obtained for the stresses are accurate and reliable even for extremely thin plates.","PeriodicalId":47168,"journal":{"name":"Journal of Applied and Computational Mechanics","volume":"62 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73386498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Application of the p-version of FEM to hierarchic rod models with reference to mechanical contact problems 考虑机械接触问题的分层杆模型p型有限元法的应用

IF 3.1

Journal of Applied and Computational Mechanics Pub Date : 2023-01-01 DOI: 10.32973/jcam.2023.002

I. Páczelt, B. Szabó, A. Baksa

引用次数: 0

Post-extrapolation for specified time-step results without interpolation in MOC-based 1D hydraulic transients and gas release computations 基于模型的一维水力瞬态和气体释放计算中指定时间步结果的后外推，无需插值

IF 3.1

Journal of Applied and Computational Mechanics Pub Date : 2023-01-01 DOI: 10.32973/jcam.2023.003

A. A. Estuti, E. Litvai

{"title":"Post-extrapolation for specified time-step results without interpolation in MOC-based 1D hydraulic transients and gas release computations","authors":"A. A. Estuti, E. Litvai","doi":"10.32973/jcam.2023.003","DOIUrl":"https://doi.org/10.32973/jcam.2023.003","url":null,"abstract":"The goal of the paper is to present a supplementary step called postextrapolation. When applied to the well-known method of characteristics (MOC), this assures the continuous use of the specified time steps or regular numerical grid without interpolations during computations of transients in 1D 2-phase flow in straight elastic pipes. The new method consists of two steps, the first being a typical MOC step, where the C− and C+ characteristics start from regular nodal points, allowing for the point of intersection to differ from a regular one. After defining the variables there the method transforms it corresponding to the near regular grid point, using the first derivatives contained in the original, nonlinear, governing equations, as evaluated numerically from the variables got earlier in the neighboring nodes. The procedure needs no interpolations; it deals with grid-point values only. Instead of the Courant-type stability conditions, shock-wave catching and smoothing techniques help to assure numerical stability between broad limits of parameters like the closing time of a valve and the initial gas content of the fluid. Comparison by runs with traditional codes under itemized boundary conditions and measurements on a simple TPV (tank-pipe-valve) setup show acceptable scatter.","PeriodicalId":47168,"journal":{"name":"Journal of Applied and Computational Mechanics","volume":"23 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74101580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of micro-shock waves in a planar magnetogasdynamic flow using the discontinuous Galerkin finite element method 用不连续伽辽金有限元法研究平面磁气动力流中的微激波

IF 3.1

Journal of Applied and Computational Mechanics Pub Date : 2022-01-01 DOI: 10.32973/jcam.2022.006

Alberto Gallottini, L. Könözsy

{"title":"Investigation of micro-shock waves in a planar magnetogasdynamic flow using the discontinuous Galerkin finite element method","authors":"Alberto Gallottini, L. Könözsy","doi":"10.32973/jcam.2022.006","DOIUrl":"https://doi.org/10.32973/jcam.2022.006","url":null,"abstract":"The present work focuses on the numerical investigation of micro-shock wave propagation in a two-dimensional magnetogasdynamic flow in the framework of the Dis- continuous Galerkin-Finite Element Method (DG-FEM). The Lorentz force has been im- plemented in the compressible, viscous Navier–Stokes equations as a source term using first-order spatial and fourth-order temporal Runge–Kutta discretization schemes. To in- vestigate the effect of the electrical conductivity on the micro-shock wave propagation, a two-dimensional micro-shock channel problem with hydraulic diameter of 2.5 mm, length of 82 mm, and no-slip boundary conditions at the left and at the right wall is considered as a benchmark problem. In this case, acoustic waves are generated behind after the rupture of the membrane that separates two states of the same gas originally at different pressure and density and both initially at rest. The magnetic field is taken into account as uniform and stationary throughout the microchannel, and the numerical simulations are performed in a short physical time, before the reflection of the waves on the lateral wall. A detailed parametric study of the temperature, density, pressure, and u-velocity is carried out by a variation of the electrical conductivity of the magnetogasdynamic flow, under the assumption of low magnetic Reynolds numbers. It has been found that the jumps of the acoustic waves become significantly intensified when the electrical conductivity of the gas is increased. It has also been observed that the presence of the Lorentz force causes an acceleration in the gasflow towards the outlet section of the microchannel at the low Knudsen number of 0.05. The outcome of this research work could be relevant to biomedical applications where the ability to control the flow in a microchannel has a significant impact on the development of small devices aimed to deliver pharmaceutical drugs in specific locations.","PeriodicalId":47168,"journal":{"name":"Journal of Applied and Computational Mechanics","volume":"21 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79674832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of the SU2 Open-Source Code for a Hypersonic Flow at Mach Number 5 5马赫数高超声速流的SU2开源代码评估

IF 3.1

Journal of Applied and Computational Mechanics Pub Date : 2022-01-01 DOI: 10.32973/jcam.2022.004

Jia-Ming Yeap, Z. Rana, L. Könözsy, K. Jenkins

{"title":"Evaluation of the SU2 Open-Source Code for a Hypersonic Flow at Mach Number 5","authors":"Jia-Ming Yeap, Z. Rana, L. Könözsy, K. Jenkins","doi":"10.32973/jcam.2022.004","DOIUrl":"https://doi.org/10.32973/jcam.2022.004","url":null,"abstract":"This paper presents the evaluation of the Stanford University Unstructured (SU2) open-source computational software package for a high Mach number 5 flow. The test case selected is an impinging shock wave turbulent boundary layer interaction (SWTBLI) on a flat plate where the experimental data of Sch¨ulein et al. [27] is used for validation purposes. Two turbulence models, the Spalart–Allmaras (SA) and the k-ω Shear Stress Transport (SST) within the SU2 code are evaluated in this study. Flow parameters, such as skin friction, wall pressure distribution and boundary layer profiles are compared with experimental values. The results demonstrate the performance of the SU2 code at a high Mach number flow and highlight its limitations in predicting fluid flow physics. At higher shock generator angles, the discrepancy between experimental and CFD data is more significant. Within the interaction and flow separation zones, a smaller separation bubble and delayed separation are predicted by the SA model while the k-ω SST model predicts early separation. Both models are able to predict wall pressure distribution correctly within the experimental values. However, discrepancies were observed in the prediction of skin friction due to the inability of the models to capture the boundary layer recovery after shock impingement.","PeriodicalId":47168,"journal":{"name":"Journal of Applied and Computational Mechanics","volume":"20 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72523122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Modeling Rapid Solidification and Melting Processes for Multiphase Flows in a Welding Technology Application 多相流快速凝固和熔化过程建模在焊接技术中的应用

IF 3.1

Journal of Applied and Computational Mechanics Pub Date : 2022-01-01 DOI: 10.32973/jcam.2022.002

Xin Xiong, L. Könözsy

{"title":"Modeling Rapid Solidification and Melting Processes for Multiphase Flows in a Welding Technology Application","authors":"Xin Xiong, L. Könözsy","doi":"10.32973/jcam.2022.002","DOIUrl":"https://doi.org/10.32973/jcam.2022.002","url":null,"abstract":"This article presents unsteady simulations of laser welding based on a rapid solidification/melting model using the ANSYS-FLUENT software package with the implementation of a UDF (User Defined Function) C code. It assumes a flat interface of liquid and gas without plasma plume, evaporation and reflection and absorption effect. In the simulations, a variety of parameters are considered with different welding speeds and laser powers. The results show that with the increase of laser power, liquid fraction and velocity, penetration depth and bead width all increase. In contrary, with the increase of welding speed, the temperature, liquid fraction, penetration depth, and bead width all decrease, while the velocity magnitude is an exception. It has also been found that the increase of welding speed distorts the pool shape and forms a long tail in temperature, liquid fraction and velocity contour. The buoyancy force did not have a significant impact on the results, while the convective term makes the velocity, temperature and liquid fraction smaller. Furthermore, the negative Marangoni shear stress makes the velocity along the height and the width direction smaller in the middle of the workpiece and larger on the edges. The simulation results show a similar tendency to that obtained by other authors. The reason for the possible differences is due to the unsteadiness of the fluid flow field and the slightly different boundary conditions imposed in the model presented here. The novelties of this work are unsteady simulations, new boundary conditions and parametric studies relevant to industrial applications.","PeriodicalId":47168,"journal":{"name":"Journal of Applied and Computational Mechanics","volume":"19 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74520543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mathematical aspects of non-Fourier heat equations 非傅立叶热方程的数学方面

IF 3.1

Journal of Applied and Computational Mechanics Pub Date : 2022-01-01 DOI: 10.32973/jcam.2022.001

R. Kovács

引用次数: 2

Two Theorems on the Torsional Rigidity of Piezoelectric Beams 压电梁扭转刚度的两个定理

IF 3.1

Journal of Applied and Computational Mechanics Pub Date : 2022-01-01 DOI: 10.32973/jcam.2022.003

I. Ecsedi, Á. Lengyel

引用次数: 0

Solutions for the vibration and stability problems of heterogenous beams with three supports using Green functions 用格林函数求解三支承非均质梁的振动和稳定性问题

IF 3.1

Journal of Applied and Computational Mechanics Pub Date : 2022-01-01 DOI: 10.32973/jcam.2022.007

L. Kiss, Messaudi Abderrazek, G. Szeidl

引用次数: 0

Fundamental solutions in the theory of thermoelastic diffusive materials with microtemperatures and microconcentrations 微温度微浓度热弹性扩散材料理论中的基本解

IF 3.1

Journal of Applied and Computational Mechanics Pub Date : 2022-01-01 DOI: 10.32973/jcam.2022.005

T. Kansal

引用次数: 0