Pub Date : 2024-06-04DOI: 10.37394/232013.2024.19.22
Cherifa Benygzer, M. Bouzit, Abderrahem Mokhefi
nvective heat transfer improvement from wavy surfaces presents a new solution in industrial engineering for composite materials, including porous medium, and nanofluids to address the wavy irregular surfaces in heat transfer devices such as a wavy solar collector, energy absorption and filtration, thermal insulation, and geothermal power plants. This technique enables the performance of engineering applications. The numerical study is performed to examine the effects of a wavy interface separating two layers in the enclosure on heat exchange rates. This paper investigates numerically the natural convection flow in a square cavity partially filled with nanofluid-porous layers separated by a wavy horizontal interface. The left and right walls of the cavity are maintained at constant hot and cold temperatures, whereas the other walls are adiabatic. The Buongiorno model is used to describe nanofluid motion, taking into account the brownian and thermophoresis effects in the cavity. The Galerkin finite element method was applied to solve the differential governing equations. The dynamic, thermal field and heat transfer have been analyzed for various parameters such as Rayleigh number (10^3 ≤ Ra ≤ 10^6), the amplitude of interface (0 ≤ A ≤ 0.1), and undulation number (0 ≤ n ≤ 9). The results reveal that the flow intensity induced by buoyancy forces is more significant in the nanofluid layer than in the porous layer, since the heat transfer is enhanced while the flow is not sensitive to variations in amplitude and number undulation, and accordingly, the decline of average Nusselt and Sherwood numbers is insignificant. The effects of controlled parameters on the structure of nanofluid flow, heat, and mass transfer rate are insignificant.
波浪形表面的对流传热改进为复合材料（包括多孔介质）和纳米流体的工业工程提供了一种新的解决方案，以解决波浪形太阳能集热器、能量吸收和过滤、隔热和地热发电厂等传热设备中的波浪形不规则表面问题。这项技术可以提高工程应用的性能。数值研究的目的是考察分隔围护结构中两层的波浪形界面对热交换率的影响。本文用数值方法研究了在一个部分充满纳米流体多孔层的正方形空腔中的自然对流。空腔的左壁和右壁保持恒定的冷热温度，而其他壁则为绝热。考虑到空腔中的布朗效应和热泳效应，采用 Buongiorno 模型来描述纳米流体的运动。伽勒金有限元法用于求解微分控制方程。分析了瑞利数（10^3 ≤ Ra ≤ 10^6）、界面振幅（0 ≤ A ≤ 0.1）和起伏数（0 ≤ n ≤ 9）等不同参数下的动态、热场和传热情况。结果表明，浮力在纳米流体层引起的流动强度比在多孔层引起的流动强度更大，因为传热增强了，而流动对振幅和起伏数的变化并不敏感，因此平均努塞尔特数和舍伍德数的下降并不明显。控制参数对纳米流体的流动结构、传热和传质速率的影响都不大。
{"title":"Effect of Wavy Interface on Natural Convection in Square Cavity Partially Filled with Nanofluid and Porous Medium using Buongiorno Model","authors":"Cherifa Benygzer, M. Bouzit, Abderrahem Mokhefi","doi":"10.37394/232013.2024.19.22","DOIUrl":"https://doi.org/10.37394/232013.2024.19.22","url":null,"abstract":"nvective heat transfer improvement from wavy surfaces presents a new solution in industrial engineering for composite materials, including porous medium, and nanofluids to address the wavy irregular surfaces in heat transfer devices such as a wavy solar collector, energy absorption and filtration, thermal insulation, and geothermal power plants. This technique enables the performance of engineering applications. The numerical study is performed to examine the effects of a wavy interface separating two layers in the enclosure on heat exchange rates. This paper investigates numerically the natural convection flow in a square cavity partially filled with nanofluid-porous layers separated by a wavy horizontal interface. The left and right walls of the cavity are maintained at constant hot and cold temperatures, whereas the other walls are adiabatic. The Buongiorno model is used to describe nanofluid motion, taking into account the brownian and thermophoresis effects in the cavity. The Galerkin finite element method was applied to solve the differential governing equations. The dynamic, thermal field and heat transfer have been analyzed for various parameters such as Rayleigh number (10^3 ≤ Ra ≤ 10^6), the amplitude of interface (0 ≤ A ≤ 0.1), and undulation number (0 ≤ n ≤ 9). The results reveal that the flow intensity induced by buoyancy forces is more significant in the nanofluid layer than in the porous layer, since the heat transfer is enhanced while the flow is not sensitive to variations in amplitude and number undulation, and accordingly, the decline of average Nusselt and Sherwood numbers is insignificant. The effects of controlled parameters on the structure of nanofluid flow, heat, and mass transfer rate are insignificant.","PeriodicalId":510564,"journal":{"name":"WSEAS TRANSACTIONS ON FLUID MECHANICS","volume":"4 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141268011","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}
Pub Date : 2024-05-14DOI: 10.37394/232013.2024.19.20
Paramesh T., Tshering Tenzin, Mohammad Sarwar, Ahmad Mujeeb Azizi, Habte Getaneh, Tamal Jana
The study of aerodynamic characteristics plays a crucial role in the design and performance evaluation of various airfoil profiles. In this study, a comprehensive investigation of the modified NACA 2412 airfoil has been carried out, focusing on its aerodynamic characteristics and performance. To improve the aerodynamic characteristics and to delay the stall, active and passive control techniques are introduced. The computational investigation is carried out using commercial software Ansys Fluent. Especially, the Reynolds-Averaged Navier Stokes (RANS) equation is numerically computed employing the K-omega SST turbulence model. The active control is implemented using four microjets, each having diameters of 3 mm, 4 mm, and 5 mm, placed upstream of the flow separation location of the uncontrolled airfoil. The jet exit velocity is maintained the same as the freestream flow velocity. For each case, the tangential orientations of the jets are varied from 2 to 10 degrees with an increment of 2 degrees. Besides, the impact of jet separation distance is also evaluated. On the other hand, the passive control method is introduced by deploying vortex generators (VG) with varying heights of 2 mm, 3 mm, and 4 mm, placed upstream of the separation location. Aerodynamic characteristics, including Lift, Drag, and Stall angle, are measured to assess performance. The study reveals that microjets with a diameter of 5 mm at a 2-degree tangential orientation perform best with a maximum of 11.33% increase in lift coefficient (Cl). For all the three sizes of microjets, the drag coefficients (Cd) are minimum for 2-degree tangential orientation. Besides, the vortex generator of height 2 mm demonstrates superior performance with a maximum of 4% increase in lift coefficient. For both cases, the stall angle of the airfoil is delayed by 28.57%. In addition, except 2mm height of the vortex generator, all other vortex generators lead to an increase in drag coefficient. Importantly, the microjets are proved to be more efficient than the vortex generator in delaying the flow separation thereby reducing the drag and increasing the aerodynamic efficiency of the airfoil.
{"title":"Improvement of Aerodynamic Performance of NACA 2412 Airfoil using Active and Passive Control Techniques","authors":"Paramesh T., Tshering Tenzin, Mohammad Sarwar, Ahmad Mujeeb Azizi, Habte Getaneh, Tamal Jana","doi":"10.37394/232013.2024.19.20","DOIUrl":"https://doi.org/10.37394/232013.2024.19.20","url":null,"abstract":"The study of aerodynamic characteristics plays a crucial role in the design and performance evaluation of various airfoil profiles. In this study, a comprehensive investigation of the modified NACA 2412 airfoil has been carried out, focusing on its aerodynamic characteristics and performance. To improve the aerodynamic characteristics and to delay the stall, active and passive control techniques are introduced. The computational investigation is carried out using commercial software Ansys Fluent. Especially, the Reynolds-Averaged Navier Stokes (RANS) equation is numerically computed employing the K-omega SST turbulence model. The active control is implemented using four microjets, each having diameters of 3 mm, 4 mm, and 5 mm, placed upstream of the flow separation location of the uncontrolled airfoil. The jet exit velocity is maintained the same as the freestream flow velocity. For each case, the tangential orientations of the jets are varied from 2 to 10 degrees with an increment of 2 degrees. Besides, the impact of jet separation distance is also evaluated. On the other hand, the passive control method is introduced by deploying vortex generators (VG) with varying heights of 2 mm, 3 mm, and 4 mm, placed upstream of the separation location. Aerodynamic characteristics, including Lift, Drag, and Stall angle, are measured to assess performance. The study reveals that microjets with a diameter of 5 mm at a 2-degree tangential orientation perform best with a maximum of 11.33% increase in lift coefficient (Cl). For all the three sizes of microjets, the drag coefficients (Cd) are minimum for 2-degree tangential orientation. Besides, the vortex generator of height 2 mm demonstrates superior performance with a maximum of 4% increase in lift coefficient. For both cases, the stall angle of the airfoil is delayed by 28.57%. In addition, except 2mm height of the vortex generator, all other vortex generators lead to an increase in drag coefficient. Importantly, the microjets are proved to be more efficient than the vortex generator in delaying the flow separation thereby reducing the drag and increasing the aerodynamic efficiency of the airfoil.","PeriodicalId":510564,"journal":{"name":"WSEAS TRANSACTIONS ON FLUID MECHANICS","volume":"11 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140979992","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}
Pub Date : 2024-05-02DOI: 10.37394/232013.2024.19.19
Karl Zammit, Howard Smith, Noel Sierra Lobo, Ioannis K. Giannopoulos
This paper presents a bioinspired, genetic-algorithm evolutionary process for Ground-Effect vehicle wing design. The study made use of a rapid aerodynamic model generation and results evaluation computational fluid dynamics vortex lattice method software, supervised by a genetic algorithm optimization Python script. The design space for the aircraft wing parametric features drew inspiration from seabirds, under the assumption of their wings being naturally evolved and partially optimized for proximity flight over water surfaces. A case study was based on the A-90 Orlyonok Russian Ekranoplan, where alternative bioinspired wing variations were proposed. The study objective was to investigate the possible increased flight aircraft performance when using bioinspired wings, as well as verify the static and dynamic aircraft stability compliance for Ground-Effect flight. The methodology presented herein along with the study results, provided an incremental step towards advancing Ground-Effect aircraft conceptual designs using computational fluid dynamics.
{"title":"Bioinspired Genetic-Algorithm Optimized Ground-Effect Wing Design: Flight Performance Benefits and Aircraft Stability Effects","authors":"Karl Zammit, Howard Smith, Noel Sierra Lobo, Ioannis K. Giannopoulos","doi":"10.37394/232013.2024.19.19","DOIUrl":"https://doi.org/10.37394/232013.2024.19.19","url":null,"abstract":"This paper presents a bioinspired, genetic-algorithm evolutionary process for Ground-Effect vehicle wing design. The study made use of a rapid aerodynamic model generation and results evaluation computational fluid dynamics vortex lattice method software, supervised by a genetic algorithm optimization Python script. The design space for the aircraft wing parametric features drew inspiration from seabirds, under the assumption of their wings being naturally evolved and partially optimized for proximity flight over water surfaces. A case study was based on the A-90 Orlyonok Russian Ekranoplan, where alternative bioinspired wing variations were proposed. The study objective was to investigate the possible increased flight aircraft performance when using bioinspired wings, as well as verify the static and dynamic aircraft stability compliance for Ground-Effect flight. The methodology presented herein along with the study results, provided an incremental step towards advancing Ground-Effect aircraft conceptual designs using computational fluid dynamics.","PeriodicalId":510564,"journal":{"name":"WSEAS TRANSACTIONS ON FLUID MECHANICS","volume":"71 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141019207","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}
Pub Date : 2024-05-02DOI: 10.37394/232013.2024.19.18
G. Vernengo
Three-dimensional effects induced by dimensional ratios on the gap resonances happening in twin hull vessels oscillating in forced vertical motion have been analyzed. They can lead to relevant consequences, such as the amplification of the inner radiated waves or the generation of standing waves in between the demi-hulls, that can have a direct effect on the operating profile of the vessel. The response of twin hull vessels in waves can be strongly affected by these resonant phenomena. Also, some of these behaviors can be exploited in the framework of wave energy conversion systems. The present analysis is carried out by using an open-source, linear, Boundary Element Method (BEM), based on the Green function approach. Mathematical backgrounds of the added mass and damping coefficients computation for a floating body under harmonic vertical oscillation are provided as well as details of the numerical discretization used in the BEM. A panel mesh sensitivity study is carried out and the numerical prediction is validated by comparison against available experimental data, another CFD solution obtained by a high-fidelity viscous solver based on the open-source libraries Open-FOAM and approximate analytic formulations. The effect of the beam ratio and the length-to-beam ratio on the resonant phenomena has been analyzed. This has been achieved by systematic variations of the geometric dimensions of the hull, focusing on the trends of the hydrodynamic coefficients, the amplitude of the radiated waves, and the location of the resonant frequencies over the analyzed range.
我们分析了在强制垂直运动中发生振荡的双壳船舶中，由尺寸比引起的间隙共振所产生的三维效应。这些影响会导致相关后果，如内部辐射波放大或在双壳之间产生驻波，从而对船舶的运行剖面产生直接影响。双壳船在波浪中的响应会受到这些共振现象的强烈影响。此外，在波浪能转换系统的框架中也可以利用其中的一些行为。本分析采用基于格林函数方法的开源线性边界元素法（BEM）进行。提供了计算谐波垂直振荡下浮体的附加质量和阻尼系数的数学背景，以及 BEM 中使用的数值离散化细节。通过与现有实验数据、基于开源库 Open-FOAM 的高保真粘性求解器获得的另一种 CFD 解法以及近似解析公式进行比较，对数值预测进行了验证。分析了梁比和长梁比对共振现象的影响。这是通过系统地改变船体的几何尺寸来实现的，重点是流体力学系数的变化趋势、辐射波的振幅以及共振频率在分析范围内的位置。
{"title":"Three-dimensional Effects on Gap-Resonances in Twin-Hull Vessels in Time-Harmonic Vertical Oscillations","authors":"G. Vernengo","doi":"10.37394/232013.2024.19.18","DOIUrl":"https://doi.org/10.37394/232013.2024.19.18","url":null,"abstract":"Three-dimensional effects induced by dimensional ratios on the gap resonances happening in twin hull vessels oscillating in forced vertical motion have been analyzed. They can lead to relevant consequences, such as the amplification of the inner radiated waves or the generation of standing waves in between the demi-hulls, that can have a direct effect on the operating profile of the vessel. The response of twin hull vessels in waves can be strongly affected by these resonant phenomena. Also, some of these behaviors can be exploited in the framework of wave energy conversion systems. The present analysis is carried out by using an open-source, linear, Boundary Element Method (BEM), based on the Green function approach. Mathematical backgrounds of the added mass and damping coefficients computation for a floating body under harmonic vertical oscillation are provided as well as details of the numerical discretization used in the BEM. A panel mesh sensitivity study is carried out and the numerical prediction is validated by comparison against available experimental data, another CFD solution obtained by a high-fidelity viscous solver based on the open-source libraries Open-FOAM and approximate analytic formulations. The effect of the beam ratio and the length-to-beam ratio on the resonant phenomena has been analyzed. This has been achieved by systematic variations of the geometric dimensions of the hull, focusing on the trends of the hydrodynamic coefficients, the amplitude of the radiated waves, and the location of the resonant frequencies over the analyzed range.","PeriodicalId":510564,"journal":{"name":"WSEAS TRANSACTIONS ON FLUID MECHANICS","volume":"44 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141022468","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}
Pub Date : 2024-03-06DOI: 10.37394/232013.2024.19.10
Ighoroje W. A. Okuyade, T. M. Abbey
The problem of unsteady MHD fluid flow past a moving vertical surface in a slip flow regime is presented. The model is built on the assumption that the flow is naturally convective with oscillating time-dependent and exponentially decaying suction and permeability, double-diffusion, viscous dissipation, and temperature gradient-dependent heat source, and non-zero tangential velocity at the wall; the fluid is viscous, incompressible, Newtonian, chemically reactive, and magnetically susceptible; the surface is porous, and electrically conductive, and thermally radiative. The governing partial differential equations are highly coupled and non-linear. For easy tractability, the equations are reduced to one-dimensional using the one-dimensional unsteady flow theory. The resulting equations are non-dimensionalized and solved using the time-dependent perturbation series solutions, and the Modified Homotopy Perturbation Method (MHPM). The solutions of the concentration, temperature, velocity, rates of mass and heat diffusion, and wall shear stress are obtained, computed, and presented graphically and quantitatively, and analyzed. The results among others, show that the increase in the: Schmidt number increases the fluid concentration, velocity, the rate of heat transfer to the fluid, and the stress on the wall, but decreases the rate of mass transfer to the fluid; Magnetic field parameter decreases the fluid velocity and stress on the wall; Slip parameter increases the flow velocity, but decreases the stress on the wall; Permeability parameter increases the flow velocity and the stress on the wall. These results are benchmarked with the reports in existing literature and they agree.
{"title":"Transient MHD Fluid Flow Past a Moving Vertical Surface in a Velocity Slip Flow Regime","authors":"Ighoroje W. A. Okuyade, T. M. Abbey","doi":"10.37394/232013.2024.19.10","DOIUrl":"https://doi.org/10.37394/232013.2024.19.10","url":null,"abstract":"The problem of unsteady MHD fluid flow past a moving vertical surface in a slip flow regime is presented. The model is built on the assumption that the flow is naturally convective with oscillating time-dependent and exponentially decaying suction and permeability, double-diffusion, viscous dissipation, and temperature gradient-dependent heat source, and non-zero tangential velocity at the wall; the fluid is viscous, incompressible, Newtonian, chemically reactive, and magnetically susceptible; the surface is porous, and electrically conductive, and thermally radiative. The governing partial differential equations are highly coupled and non-linear. For easy tractability, the equations are reduced to one-dimensional using the one-dimensional unsteady flow theory. The resulting equations are non-dimensionalized and solved using the time-dependent perturbation series solutions, and the Modified Homotopy Perturbation Method (MHPM). The solutions of the concentration, temperature, velocity, rates of mass and heat diffusion, and wall shear stress are obtained, computed, and presented graphically and quantitatively, and analyzed. The results among others, show that the increase in the: Schmidt number increases the fluid concentration, velocity, the rate of heat transfer to the fluid, and the stress on the wall, but decreases the rate of mass transfer to the fluid; Magnetic field parameter decreases the fluid velocity and stress on the wall; Slip parameter increases the flow velocity, but decreases the stress on the wall; Permeability parameter increases the flow velocity and the stress on the wall. These results are benchmarked with the reports in existing literature and they agree.","PeriodicalId":510564,"journal":{"name":"WSEAS TRANSACTIONS ON FLUID MECHANICS","volume":"16 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140260945","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}
Pub Date : 2024-03-06DOI: 10.37394/232013.2024.19.11
Durdimurod Durdiyev, I. Safarov, M. Teshaev
The oscillatory process of a viscoelastic shell of a cylindrical tipe filled with a liquid is considered. Unlike other works, this paper focuses on the viscoelastic properties of a cylindrical shell and a liquid. Differential equations for joint vibrations of a shell and liquid are obtained by the equations of a thin shell that satisfies the Kirchhoff–Love hypotheses, and the equations of motion of a viscous liquid obey the Navier–Stokes equation. After simple transformations, the integro-differential equations are reduced to ordinary differential equations and solved using Godunov's orthogonal run method combined with Muller's method. Based on the developed algorithm, natural frequencies and corresponding vibration modes were obtained. For steady-state oscillations, all eigenvalues and eigenmodes turned out to be complex. For the first time, it was found that the damping coefficient branches out after certain values of wave numbers. It was found that the motion in a cylindrical shell is localized on the surface of the shell. At slow localization, starting from a certain wave number, the natural oscillations become aperiodic.
{"title":"Propagation of Waves in a Fluid in a Thin Elastic Cylindrical Shell","authors":"Durdimurod Durdiyev, I. Safarov, M. Teshaev","doi":"10.37394/232013.2024.19.11","DOIUrl":"https://doi.org/10.37394/232013.2024.19.11","url":null,"abstract":"The oscillatory process of a viscoelastic shell of a cylindrical tipe filled with a liquid is considered. Unlike other works, this paper focuses on the viscoelastic properties of a cylindrical shell and a liquid. Differential equations for joint vibrations of a shell and liquid are obtained by the equations of a thin shell that satisfies the Kirchhoff–Love hypotheses, and the equations of motion of a viscous liquid obey the Navier–Stokes equation. After simple transformations, the integro-differential equations are reduced to ordinary differential equations and solved using Godunov's orthogonal run method combined with Muller's method. Based on the developed algorithm, natural frequencies and corresponding vibration modes were obtained. For steady-state oscillations, all eigenvalues and eigenmodes turned out to be complex. For the first time, it was found that the damping coefficient branches out after certain values of wave numbers. It was found that the motion in a cylindrical shell is localized on the surface of the shell. At slow localization, starting from a certain wave number, the natural oscillations become aperiodic.","PeriodicalId":510564,"journal":{"name":"WSEAS TRANSACTIONS ON FLUID MECHANICS","volume":"4 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140262251","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}
Pub Date : 2024-02-29DOI: 10.37394/232013.2024.19.8
A. El Harfouf, Rachid Herbazi, S. Mounir, H. Mes-Adi, A. Wakif
A numerical investigation is conducted into a two-dimensional mathematical model of magnetized unsteady incompressible Williamson fluid flow over a sensor surface with fixed thermal conductivity and external squeezing accompanied by viscous dissipation effect. Based on the flow geometry under consideration, the current flow model was created. The momentum equation takes into consideration the magnetic field when describing the impact of Lorentz forces on flow behavior. The energy equation takes varying thermal conductivity into account while calculating heat transmission. The extremely complex nonlinear, unstable governing flow equations for the now under investigation are coupled in nature. Due to the inability of analytical or direct methods, the Runge-Kutta scheme (RK-4) via similarity transformations approach is used to tackle the physical problem under consideration. The physical behavior of various control factors on the flow phenomena is described using graphs and tables. For increasing values of the Weissenberg parameter and the permeable velocity parameter, the temperature boundary layer thickens. As the permeable velocity parameter and squeezed flow index increased, the velocity profile shrank. The velocity profile grows as the magnetic number rises. Squeezed flow magnifying increases the Nusselt number's magnitude. Furthermore, the extremely complex nonlinear complex equations that arise in fluid flow issues are quickly solved by RK-4. The current findings in this article closely align with the findings that have been reported in the literature.
{"title":"Unsteady Compressed Williamson Fluid Flow Behavior under the Influence of a Fixed Magnetic Field (Numerical Study)","authors":"A. El Harfouf, Rachid Herbazi, S. Mounir, H. Mes-Adi, A. Wakif","doi":"10.37394/232013.2024.19.8","DOIUrl":"https://doi.org/10.37394/232013.2024.19.8","url":null,"abstract":"A numerical investigation is conducted into a two-dimensional mathematical model of magnetized unsteady incompressible Williamson fluid flow over a sensor surface with fixed thermal conductivity and external squeezing accompanied by viscous dissipation effect. Based on the flow geometry under consideration, the current flow model was created. The momentum equation takes into consideration the magnetic field when describing the impact of Lorentz forces on flow behavior. The energy equation takes varying thermal conductivity into account while calculating heat transmission. The extremely complex nonlinear, unstable governing flow equations for the now under investigation are coupled in nature. Due to the inability of analytical or direct methods, the Runge-Kutta scheme (RK-4) via similarity transformations approach is used to tackle the physical problem under consideration. The physical behavior of various control factors on the flow phenomena is described using graphs and tables. For increasing values of the Weissenberg parameter and the permeable velocity parameter, the temperature boundary layer thickens. As the permeable velocity parameter and squeezed flow index increased, the velocity profile shrank. The velocity profile grows as the magnetic number rises. Squeezed flow magnifying increases the Nusselt number's magnitude. Furthermore, the extremely complex nonlinear complex equations that arise in fluid flow issues are quickly solved by RK-4. The current findings in this article closely align with the findings that have been reported in the literature.","PeriodicalId":510564,"journal":{"name":"WSEAS TRANSACTIONS ON FLUID MECHANICS","volume":"11 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140409919","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}
Pub Date : 2024-02-29DOI: 10.37394/232013.2024.19.9
Pankaj Prasad Dwivedi, Dilip Kumar Sharma
Cutting fluids are used in machining processes to increase the quality of machined surfaces, extend the life of tools, and lessen the effect of friction and heat on contact surfaces. The least costly, least hazardous to the environment, and least poisonous lubricant would be the perfect choice. It should also be resistant to low temperatures, have high lubricating qualities, be recyclable, and have stability against oxidation, hydrolysis, and heat. Its viscosity should also fall between the ideal range and not exceed it. Taking the needed properties of the cutting fluids into consideration, for the machining process choosing the best cutting fluid is essential. Five types of cutting fluids are examined in this paper that are often used in machining operations: canola oil, mineral oil, synthetic ester, PAG (Polyalkylene Glycol), and TMPTO (trimethylolpropane trioleate). In this study, the Multicriteria decision-making (MCDM) techniques were used to identify the best choice of cutting fluids based on several parameters, such as low temperature, toxicity, lubricating ability, hydrolytic stability, thermal stability, viscosity index, oxidative stability, and cost. The most popular TOPSIS methods and Shannon's Entropy were utilized to choose these cutting fluids optimally. The TOPSIS approach is used to calculate the final ranking, and Shannon’s entropy method is utilized to calculate the weight of the criterion. According to the result with the more lucid rating, PAG cutting fluid was shown to be the most effective, followed by synthetic ester in second place, as well as last place achieved by vegetable-based canola oil.
{"title":"A study for an Optimization of Cutting Fluids in Machining Operations by TOPSIS and Shannon Entropy Methods","authors":"Pankaj Prasad Dwivedi, Dilip Kumar Sharma","doi":"10.37394/232013.2024.19.9","DOIUrl":"https://doi.org/10.37394/232013.2024.19.9","url":null,"abstract":"Cutting fluids are used in machining processes to increase the quality of machined surfaces, extend the life of tools, and lessen the effect of friction and heat on contact surfaces. The least costly, least hazardous to the environment, and least poisonous lubricant would be the perfect choice. It should also be resistant to low temperatures, have high lubricating qualities, be recyclable, and have stability against oxidation, hydrolysis, and heat. Its viscosity should also fall between the ideal range and not exceed it. Taking the needed properties of the cutting fluids into consideration, for the machining process choosing the best cutting fluid is essential. Five types of cutting fluids are examined in this paper that are often used in machining operations: canola oil, mineral oil, synthetic ester, PAG (Polyalkylene Glycol), and TMPTO (trimethylolpropane trioleate). In this study, the Multicriteria decision-making (MCDM) techniques were used to identify the best choice of cutting fluids based on several parameters, such as low temperature, toxicity, lubricating ability, hydrolytic stability, thermal stability, viscosity index, oxidative stability, and cost. The most popular TOPSIS methods and Shannon's Entropy were utilized to choose these cutting fluids optimally. The TOPSIS approach is used to calculate the final ranking, and Shannon’s entropy method is utilized to calculate the weight of the criterion. According to the result with the more lucid rating, PAG cutting fluid was shown to be the most effective, followed by synthetic ester in second place, as well as last place achieved by vegetable-based canola oil.","PeriodicalId":510564,"journal":{"name":"WSEAS TRANSACTIONS ON FLUID MECHANICS","volume":"28 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140412358","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}
Pub Date : 2024-02-23DOI: 10.37394/232013.2024.19.7
Javier Armañanzas, Marina Alcalá, Juan Pablo Fuertes, Javier Leon, Alexia Torres, Miguel Gil
In the present research work, a device for electrical energy generation to be used in water pipelines has been designed, simulated, and tested. To achieve this, a study of the most influential parameters involved in the experiment has been carried out and both, the turbine model and the geometry of the experimental test pipe, have been selected through CFD simulations. Next, the Design of Experiments (DOE) has been used to obtain the configuration with a higher energy extraction from running water. Finally, the turbine and the test pipe section have been manufactured by 3D printing and the experimental tests have been carried out with the optimal configuration to validate the results obtained in the CFD simulations. To simulate the exchange of energy between the water and the turbine, the CFD software SIMULIA XFlow has been used.
{"title":"Design and Experimentation of a Hydrokinetic Turbine for Electricity Generation in Closed Pipes","authors":"Javier Armañanzas, Marina Alcalá, Juan Pablo Fuertes, Javier Leon, Alexia Torres, Miguel Gil","doi":"10.37394/232013.2024.19.7","DOIUrl":"https://doi.org/10.37394/232013.2024.19.7","url":null,"abstract":"In the present research work, a device for electrical energy generation to be used in water pipelines has been designed, simulated, and tested. To achieve this, a study of the most influential parameters involved in the experiment has been carried out and both, the turbine model and the geometry of the experimental test pipe, have been selected through CFD simulations. Next, the Design of Experiments (DOE) has been used to obtain the configuration with a higher energy extraction from running water. Finally, the turbine and the test pipe section have been manufactured by 3D printing and the experimental tests have been carried out with the optimal configuration to validate the results obtained in the CFD simulations. To simulate the exchange of energy between the water and the turbine, the CFD software SIMULIA XFlow has been used.","PeriodicalId":510564,"journal":{"name":"WSEAS TRANSACTIONS ON FLUID MECHANICS","volume":"5 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140436362","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}
Pub Date : 2024-02-01DOI: 10.37394/232013.2024.19.4
Feras M. Al Faqih, K. Rafique, Sehar Aslam, Mohammed Z. Swalmeh
Several industrial developments such as polymer extrusion in metal spinning and continuous metal casting include energy transmission and flow over a stretchy surface. In this paper, the stagnation point flow of micropolar nanofluid over a slanted surface is presenting also considering the influence of thermal radiations. Buongiorno’s nanoliquid model is deployed to recover the thermophoretic effects. By using similarity transformations, the governing boundary layer equations are transformed into ordinary differential equations. The Keller-box approach is used to solve transformed equations numerically. The numerical outcomes are presented in tabular and graphical form. A comparison of the outcomes attained with previously published results is done after providing the entire formulation of the Keller-Box approach for the flow problem under consideration. It has been found that the reduced sherwood number grows for increasing values of radiation parameter while, reduced Nusselt number and skin friction coefficient decreases. Furthermore, the skin-friction coefficient increases as the inclination factor increases, but Nusselt and Sherwood's numbers decline.
{"title":"Numerical Analysis on Stagnation Point Flow of Micropolar Nanofluid with Thermal Radiations over an Exponentially Stretching Surface","authors":"Feras M. Al Faqih, K. Rafique, Sehar Aslam, Mohammed Z. Swalmeh","doi":"10.37394/232013.2024.19.4","DOIUrl":"https://doi.org/10.37394/232013.2024.19.4","url":null,"abstract":"Several industrial developments such as polymer extrusion in metal spinning and continuous metal casting include energy transmission and flow over a stretchy surface. In this paper, the stagnation point flow of micropolar nanofluid over a slanted surface is presenting also considering the influence of thermal radiations. Buongiorno’s nanoliquid model is deployed to recover the thermophoretic effects. By using similarity transformations, the governing boundary layer equations are transformed into ordinary differential equations. The Keller-box approach is used to solve transformed equations numerically. The numerical outcomes are presented in tabular and graphical form. A comparison of the outcomes attained with previously published results is done after providing the entire formulation of the Keller-Box approach for the flow problem under consideration. It has been found that the reduced sherwood number grows for increasing values of radiation parameter while, reduced Nusselt number and skin friction coefficient decreases. Furthermore, the skin-friction coefficient increases as the inclination factor increases, but Nusselt and Sherwood's numbers decline.","PeriodicalId":510564,"journal":{"name":"WSEAS TRANSACTIONS ON FLUID MECHANICS","volume":"37 30","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139684205","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：