Journal of the Serbian Society for Computational Mechanics最新文献

{"title":"EFFECT OF VERTICAL POSITION OF HEATED SQUARE OBSTACLE ON NATURAL CONVECTION IN POROUS CAVITIES SATURATED BY A NANOFLUID USING BUONGIORNO’S TWO PHASE MODEL","authors":"F. Khelif, M. Helmaoui, M. Bouzit, Abderrahim Mokhefi","doi":"10.24874/jsscm.2022.16.01.07","DOIUrl":"https://doi.org/10.24874/jsscm.2022.16.01.07","url":null,"abstract":"Laminar flow, heat transfer and mass transfer of nanofluid in a porous medium have been studied using Buongiorno’s two phase model. The porous medium in place is a non-uniform octagonal shape. In order to increase the rate of heat transfer within the porous cavity, it has been equipped with a heated square at different vertical positions from position 1 (P1) to position 5 (P5). The left wall of this cavity is maintained at a high temperature and a unit volume fraction; whereas the right wall is exposed to a low temperature and a canceled volume fraction, and the other walls have been assumed to be adiabatic. The purpose of this paper is to highlight the effect of the heated square at different vertical positions on the evolution of the hydrodynamic, thermal and mass profiles taking into account the influence of certain parameters, such as: Rayleigh number (102≤Ra≤104), Darcy number (10-6≤Da≤10-2), thermophoresis ratio (0.1 ≤ Nt ≤ 1), buoyancy ratio (0.1 ≤ Nr ≤ 1), Brownian motion ratio (0.1 ≤ Nb ≤ 1) and Lewis number (0.1 ≤ Le ≤ 1). The physical phenomenon studied is governed by the Navier-Stokes equations coupled with the energy equation and the mass conservation equation (continuity of nanoparticles). These differential equations of boundary conditions are solved using the finite element method. The results show that an increase in the Rayleigh number and the Darcy number improves natural convection, leading to an increase in the Nusselt number at the square. It is also found that the lowest values of the Nusselt number are located at the extremities of the cavity while the highest are located at the intermediate position between the positions P3 and P4 regardless of the values of the different parameters. On the other hand, an increase in the Darcy number leads to an increase in the vertical and horizontal velocity where the highest values are located at position P4.","PeriodicalId":42945,"journal":{"name":"Journal of the Serbian Society for Computational Mechanics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44406379","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}

{"title":"A SUPERIMPOSED VALVELESS MICROPUMP USING NEW CHANNELS FOR OPTIMAL DRUG DELIVERY","authors":"Ahmed Slami, S. Soulimane","doi":"10.24874/jsscm.2022.16.01.04","DOIUrl":"https://doi.org/10.24874/jsscm.2022.16.01.04","url":null,"abstract":"In this paper, we propose a valveless micropump with an improved inlet/outlet channel configuration for biomedical applications. To do so, we added curved parts known as \"ears\" to a standard diffuser/nozzle shape. This new design will enlarge the flow rate values between both directions for the purpose of improving the valveless micropump efficiency. After that, the new channel is incorporated into a double valveless micropump superimposed on each other making the diaphragm in sandwich. This kind of micropump shows no reflux at its common outlet and good reliability due to the new design of the diffuser/nozzle channel. COMSOL Multiphysics software is used to model and simulate, under Fluid-Structure Interaction (FSI) physic, the complete system of the superimposed valveless micropump (SVM). The results are promising and show that our kind of micropump is necessary for medication injection because of the no backflow at its common outlet, and also because of the increase in its efficiency.","PeriodicalId":42945,"journal":{"name":"Journal of the Serbian Society for Computational Mechanics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48872329","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}

{"title":"MIXED-MODE STRESS INTENSITY FACTOR EVALUATION BY INTERACTION INTEGRAL METHOD UNDER THERMAL AND MECHANICAL LOADS","authors":"Ait Ferhat Yazid, Blaoui Mohamed Mossaab, Chorfi Hichem, Abacha Ilyes, Benchikh Lilia, Kebaili Maya, B. Abdelkader","doi":"10.24874/jsscm.2022.16.01.08","DOIUrl":"https://doi.org/10.24874/jsscm.2022.16.01.08","url":null,"abstract":"The objective of this study is to present numerical aspects related to the implementation of the interaction integral method for the purpose of determining the stress intensity factors in mode I and mixed-mode crack problems of functionally graded materials (FGM) and homogenous materials for a different form of cracking. This numerical development is based on the use of the finite element method (FEM), by the coupling of the Ansys-Matlab calculation codes. To validate the accuracy and reliability of the approach, the results obtained will be compared with other numerical results in the literature. The interaction integral method is one of the methods most compatible with the formulation of the finite element method. Therefore, we are interested in this study, in terms of the presentation of necessary steps which allow the resolution of a problem by finite elements for the mechanical problems. It is very important to note that the principle of the implementation of the “Integral M” technique is using scripts based on the coupling of two commercial software.","PeriodicalId":42945,"journal":{"name":"Journal of the Serbian Society for Computational Mechanics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47962655","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}

{"title":"FLEXURAL ANALYSIS OF THERMALLY LOADED SYMMETRIC SANDWICH BEAM","authors":"Sanjay Kantrao Kulkarni, Yuwaraj Marotrao Ghugal","doi":"10.24874/jsscm.2022.16.01.03","DOIUrl":"https://doi.org/10.24874/jsscm.2022.16.01.03","url":null,"abstract":"In the present paper, an attempt has been made to study the effect of temperature gradient on simply supported symmetric sandwich beam. A Navier’s solution technique is used. The temperature profile is assumed to be linear across the thickness of a sandwich beam. A higher order beam theory (HBT) is used to include the effect of shear deformation on thermal flexural response of the sandwich beam. The theory satisfies the shear stress free boundary condition at the top and bottom surfaces of the sandwich beam. No shear correction factor is required. The principle of virtual work is used to obtain the governing equations and boundary conditions. A program has been developed in FORTRAN-77 to obtain thermal stresses and displacements in the sandwich beam for various aspect ratios. The numerical results are presented for moderately thick and thin sandwich beams to assess the performance of the theory. The validity of the present theory is verified by comparing the results with the results available in the literature. The present results are in good agreement with the results of other theories.","PeriodicalId":42945,"journal":{"name":"Journal of the Serbian Society for Computational Mechanics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47201173","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}

{"title":"THE EFFECT OF THERMOPHYSICAL PROPERTIES ON NONLINEAR THERMAL-SOLUTAL CONVECTIVE FLOW OF CASSON NANOFLUID OVER AN INCLINED SURFACE WITH HIGHER ORDER CHEMICAL REACTION","authors":"Timothy Lanre Oyekunle, Mojeed Taiwo Akolade, Samson Ademola Agunbiade","doi":"10.24874/jsscm.2022.16.01.06","DOIUrl":"https://doi.org/10.24874/jsscm.2022.16.01.06","url":null,"abstract":"The combined effect of Soret-Dufour, higher-order chemical reaction and variable thermophysical properties on nonlinear thermal and solutal convective flow of a non-Newtonian fluid (Casson nanofluid) over a slanted surface is analyzed. The nonlinear dimensionless equations governing the fluid flow are transformed into ordinary differential equations, using suitable similarity transformation variables. The flow fields and some characteristic numerical results are obtained from these equations, using collocation method with assumed Legendre functions of the first kind. These results are presented in the form of graphs and tables showing the impact of various parameters on the fluid flow, heat and mass characteristics. It is observed that a rise in chemical reaction parameter decreases the nanoparticle volume fraction while a higher order of chemical reaction makes it elevated. The velocity increases and temperature decreases with a rise in nonlinear thermal convection and higher value of nonlinear solutal convection has effect on the rise of velocity distribution.","PeriodicalId":42945,"journal":{"name":"Journal of the Serbian Society for Computational Mechanics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42654074","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}

{"title":"ON THE EQUILIBRIUM OF STRATIFIED VISCOELASTIC PLASMA WITH QUANTUM PRESSURE AND SUSPENDED PARTICLES SATURATING POROUS MEDIUM","authors":"A. Thakur, Veena Sharma, Gian. C. Rana","doi":"10.24874/jsscm.2022.16.01.02","DOIUrl":"https://doi.org/10.24874/jsscm.2022.16.01.02","url":null,"abstract":"Stability of stratified incompressible viscoelastic plasma arranged in horizontal strata with quantum pressure and dust particles saturated by a porous medium is investigated. The rheology of the plasma is described by the Walters (model B). The set of non-linear partial differential equations defining the physical system are reduced to linear ordinary differential equations by using the perturbation method, linear theory and normal mode technique. The density, viscosity, viscoelasticity and quantum pressure are assumed to stratify exponentially along the vertical, to obtain exact solutions satisfying the physical boundary conditions and the dispersion relation. The values of growth rate of the unstable perturbed modes are computed numerically to investigate roles that the various variables play on the stability on the considered physical system and are shown graphically. It is observed that the suspended dust particles density and relaxation time factor have a destabilizing effect on the system; whereas viscoelasticity in the presence of suspended dust particles lead to more damping in the frequency of perturbed waves. This work finds applications in diverse fields viz. modern technology, industries, astrophysics, petroleum oil additives, equipment of aero planes etc.","PeriodicalId":42945,"journal":{"name":"Journal of the Serbian Society for Computational Mechanics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48224853","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}

{"title":"EXPERIMENTAL AND NUMERICAL INVESTIGATIONS OF A TURBULENT BOUNDARY LAYER UNDER VARIABLE TEMPERATURE GRADIENTS","authors":"A. Berkache, Salah Amroune, Ali Golbaf, Barhm Mohamad","doi":"10.24874/jsscm.2022.16.01.01","DOIUrl":"https://doi.org/10.24874/jsscm.2022.16.01.01","url":null,"abstract":"In this article we present an experimental and numerical study of the behavior of the boundary layer type viscous flow in the presence of the thermal effect. The flow was held in a three-dimensional field with a uniform infinite velocity in the case of an adiabatic wall with heat input. The presented experimental work was performed in the Thermal Laboratory (LET) of the Prime Institute of Poitiers (France). It describes the analysis of a turbulent boundary layer created in a wind tunnel on the surface of a flat plate covered with epoxy resin. An HP 6012A power supply system was used to provide circulating heat flux to heat the flat plate to 80°C by the Joule effect. The numerical result shows a clear difference in the evolution of the thermal boundary layer between the three temperatures of the wall.","PeriodicalId":42945,"journal":{"name":"Journal of the Serbian Society for Computational Mechanics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48231984","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}

{"title":"BLOOD FLOW IN ARTERIAL BIFURCATION CALCULATED BY TURBULENT FINITE ELEMENT MODEL","authors":"A. Nikolic, M. Topalovic, V. Simić, M. Blagojevic","doi":"10.24874/jsscm.2021.15.02.08","DOIUrl":"https://doi.org/10.24874/jsscm.2021.15.02.08","url":null,"abstract":"In this paper, turbulent fluid flow is analyzed using a two-equation turbulent finite element model that can calculate values in the viscous sublayer. Implicit integration of the equations is used for determining the fluid velocity, fluid pressure, turbulence, kinetic energy, and dissipation of turbulent kinetic energy. These values are calculated in the finite element nodes for each step of the incremental-iterative procedure. Developed turbulent finite element model, with the customized generation of finite element meshes, is used for calculating complex blood flow problems. Analysis of results shows that a cardiologist can use the proposed tools and methods for investigating the hemodynamic conditions inside the bifurcation of arteries.","PeriodicalId":42945,"journal":{"name":"Journal of the Serbian Society for Computational Mechanics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48902091","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}

{"title":"EXPERIMENTAL ELECTROCHEMOTHERAPY USING NOVEL DESIGN SINGLE NEEDLE DEVICE","authors":"A. Cvetkovic, D. Cvetković, D. Milasinovic, N. Jovicic, Nikola Miailović, D. Nikolić, S. Mitrovic, Nenad D Filipović","doi":"10.24874/jsscm.2021.15.02.06","DOIUrl":"https://doi.org/10.24874/jsscm.2021.15.02.06","url":null,"abstract":"This is a feasibility study for the application of a novel concept of single-needle device for localized chemotherapy. Systemic chemotherapy has numerous and severe side effects. To conduct localized (electro)chemotherapy, we designed a novel device that does not currently exist on the market. Electrochemotherapy is based on the cell membranes temporary or permanent permeabilization using an electric current of defined characteristics. Electroporation can be reversible, when after a period of opened pores and membrane permeability increasing, membranes and cells return to their original state without damage. Electroporation can be an irreversible process when the pores on the membrane remain permanently open, electrolyte imbalance occurs resulting in cell death. Electrochemotherapy involves a combination of cytostatics and reversible electroporation, when pores on the cell membrane are temporarily opened and, during that short period, a large amount of cytostatic is entered into the cell, which is a macromolecule that would not normally penetrate the cell. After closing the pores, the cytostatic remains trapped in the cell in large quantities, multiplying its effect. In this paper, we present a feasibility study of electroporation application in irreversible mode without the use of cytostatics. Fresh porcine liver tissue was used to show that the constructed equipment was effective, thus opening the way for further investigations using reversible electroporation with the application of cytostatics, which would represent localized electrochemotherapy. We penetrated the virtual tumor area (liver metastases) with a specially designed needle with electrodes that generate an electric field and apply electroporation in the target tissue. We have shown that the constructed novel design single needle equipment for electroporation is effective on the experimental model of isolated porcine liver. Further steps in our study will be the testing of electrochemotherapy in an experimental animal model in vivo.","PeriodicalId":42945,"journal":{"name":"Journal of the Serbian Society for Computational Mechanics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46773908","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}

{"title":"MOLECULAR DYNAMICS OBSERVATION OF DISCRETENESS OF THE MASS DISTRIBUTION DURING NANOSCALE FRAGMENTATION","authors":"S. Mastilovic","doi":"10.24874/jsscm.2021.15.02.02","DOIUrl":"https://doi.org/10.24874/jsscm.2021.15.02.02","url":null,"abstract":"Molecular dynamics simulations of the rigid-anvil collision test are performed by using a two-dimensional computational setup that mimics the traditional ballistic Taylor test. In this extensively utilized computational setup, the slender nanoscale projectiles collide with a rigid wall with hypersonic striking velocities ranging from 3 km/s to 30 km/s. The projectiles used in these simulations are flat-ended, monocrystalline, nanoscale bars prepared at zero temperature. The Poisson hyper-exponential distribution with the logarithmic binning is used to capture the fragment mass (size) distribution under the constraint of the relatively small specimen size 15×100 nm. The objective is to highlight the occurrence of certain discreteness of the fragment mass distribution observed both in time (during the fragment debris evolution) and across the striking velocity field (for the final fragmentation states that correspond to the stationary distributions).","PeriodicalId":42945,"journal":{"name":"Journal of the Serbian Society for Computational Mechanics","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44423770","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}