Pub Date : 2024-03-04DOI: 10.37934/cfdl.16.7.118135
Srinu Anagandula, K. Sreeram Reddy
Research has been conducted on the study of the velocity and thermal slips' impact on the Williamson fluid flow above a stretching sheet in the existence of an inclined magnetic field and Radiation. By applying the proper similarity conversions, the governing equations (PDEs) are reduced to a set of non-linear ODEs, and a numerical solution is produced by using MATLAB in-built solver bvp4c package. The impacts of the dimensionless characteristics on the flow patterns are analyzed visually, and the values of the friction, Nusselt, and mass transfer quantities are tabulated to exemplify how the various physical factors have an influence. We noted that the velocity profile enhances the rising estimations of velocity slip and the temperature profile increases with Q increase.
{"title":"Velocity and Thermal Slips Impact on the Williamson Fluid Flow above a Stretching Sheet in the Existence of Radiation and Inclined Magnetic Field","authors":"Srinu Anagandula, K. Sreeram Reddy","doi":"10.37934/cfdl.16.7.118135","DOIUrl":"https://doi.org/10.37934/cfdl.16.7.118135","url":null,"abstract":"Research has been conducted on the study of the velocity and thermal slips' impact on the Williamson fluid flow above a stretching sheet in the existence of an inclined magnetic field and Radiation. By applying the proper similarity conversions, the governing equations (PDEs) are reduced to a set of non-linear ODEs, and a numerical solution is produced by using MATLAB in-built solver bvp4c package. The impacts of the dimensionless characteristics on the flow patterns are analyzed visually, and the values of the friction, Nusselt, and mass transfer quantities are tabulated to exemplify how the various physical factors have an influence. We noted that the velocity profile enhances the rising estimations of velocity slip and the temperature profile increases with Q increase.","PeriodicalId":9736,"journal":{"name":"CFD Letters","volume":"18 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140266163","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}
Mahendra Indiaryanto Hendra, Ketut Suastika, Taufiq Arif Setyanto
The hydrodynamic performance of the B-series propeller can be determined by calculating the polynomial equation published by MARIN. Furthermore, analysis and evaluation of B-series propeller modifications can be done by varying the camber ratio of the foil. The camber ratio affects the lift force on the propeller foil, directly affecting the propeller thrust and torque. Numerical calculations were carried out using Computational Fluids Dynamics (CFD), based on Reynolds Averaged Navier Stokes Equations (RANSE) and turbulence model in the form of explicit algebraic stress models (EASM). The overall results of this study show an increase in efficiency of 4.182 on the foil with a camber ratio of 2.2% when compared to the foil camber ratio of 0%.
B 系列螺旋桨的水动力性能可通过计算 MARIN 公布的多项式方程来确定。此外,还可以通过改变桨叶的外倾角比来分析和评估 B 系列螺旋桨的改型。外倾角比会影响螺旋桨箔片上的升力,直接影响螺旋桨的推力和扭矩。计算流体动力学(CFD)基于雷诺平均纳维-斯托克斯方程(RANSE)和显式代数应力模型(EASM)形式的湍流模型进行了数值计算。研究的总体结果表明,与外倾率为 0% 的箔片相比,外倾率为 2.2% 的箔片的效率提高了 4.182%。
{"title":"Hydrodynamic Performance Analysis of Camber Ratio Variations on B-series Propeller Types","authors":"Mahendra Indiaryanto Hendra, Ketut Suastika, Taufiq Arif Setyanto","doi":"10.37934/cfdl.16.7.3953","DOIUrl":"https://doi.org/10.37934/cfdl.16.7.3953","url":null,"abstract":"The hydrodynamic performance of the B-series propeller can be determined by calculating the polynomial equation published by MARIN. Furthermore, analysis and evaluation of B-series propeller modifications can be done by varying the camber ratio of the foil. The camber ratio affects the lift force on the propeller foil, directly affecting the propeller thrust and torque. Numerical calculations were carried out using Computational Fluids Dynamics (CFD), based on Reynolds Averaged Navier Stokes Equations (RANSE) and turbulence model in the form of explicit algebraic stress models (EASM). The overall results of this study show an increase in efficiency of 4.182 on the foil with a camber ratio of 2.2% when compared to the foil camber ratio of 0%.","PeriodicalId":9736,"journal":{"name":"CFD Letters","volume":"46 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140080626","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}
The study investigates the flow characteristics of spherical shaped TiO2 –Ag hybrid nanofluid with water as a base fluid passing through a wet porous rectangular moving fin with a focus on understanding the effects of nanoparticle concentration on the heat transfer rate. The fin under consideration are subjected to boundary conditions, insulated and convective tips. Hybrid nanofluid that combine nanoparticles with conventional base fluids have potentially enhanced thermal conductivity and heat transfer properties in engineering applications. The energy balance equation containing the parameters that effect the flow of heat transfer rate is non- dimensionalized and solved numerically using 3-stage Lobatto - IIIa formula with appropriate boundary conditions. The simulation result shows the impact of different parameters on the flow and heat transfer properties of the hybrid nanofluid obtained by mixing spherical shaped TiO2 –Ag hybrid nanoparticles with water as base fluid. It is observed that the fin shows significant heat transfer rate in a convective tip relative to an insulated tip. The findings contribute to the understanding of hybrid nanofluid flow and its potential application in the design and optimization of thermal management system. It also facilitates the ground work for research in the field of nano fluid based cooling system. The observation from the graphical illustration shows that the rise in the thermal conductivity of the base fluid by 23% increases the conduction heat transfer as well as the temperature distribution by 10%. The natural convection and radiation are the key parameters that determines the heat transfer rate from the surface to the surrounding. In our investigation, enhancing the Nc,Nr parameters by 50% and 25%, the temperature distribution profile is reduced by about 13% and 6% respectively. The increase in the Pe number by 100% results in a rise in the temperature distribution by 8%.
{"title":"Performance Analysis of Wet Porous Moving Fin under the Influence of Spherical Shaped TiO2- Ag Hybrid Nanoparticles in a Water Based Fluid","authors":"Ammembal Gopalkrishna Pai, Rekha G. Pai, Lavanya B, Vinay Madhusudanan, Sanjana T.D","doi":"10.37934/cfdl.16.7.105117","DOIUrl":"https://doi.org/10.37934/cfdl.16.7.105117","url":null,"abstract":"The study investigates the flow characteristics of spherical shaped TiO2 –Ag hybrid nanofluid with water as a base fluid passing through a wet porous rectangular moving fin with a focus on understanding the effects of nanoparticle concentration on the heat transfer rate. The fin under consideration are subjected to boundary conditions, insulated and convective tips. Hybrid nanofluid that combine nanoparticles with conventional base fluids have potentially enhanced thermal conductivity and heat transfer properties in engineering applications. The energy balance equation containing the parameters that effect the flow of heat transfer rate is non- dimensionalized and solved numerically using 3-stage Lobatto - IIIa formula with appropriate boundary conditions. The simulation result shows the impact of different parameters on the flow and heat transfer properties of the hybrid nanofluid obtained by mixing spherical shaped TiO2 –Ag hybrid nanoparticles with water as base fluid. It is observed that the fin shows significant heat transfer rate in a convective tip relative to an insulated tip. The findings contribute to the understanding of hybrid nanofluid flow and its potential application in the design and optimization of thermal management system. It also facilitates the ground work for research in the field of nano fluid based cooling system. The observation from the graphical illustration shows that the rise in the thermal conductivity of the base fluid by 23% increases the conduction heat transfer as well as the temperature distribution by 10%. The natural convection and radiation are the key parameters that determines the heat transfer rate from the surface to the surrounding. In our investigation, enhancing the Nc,Nr parameters by 50% and 25%, the temperature distribution profile is reduced by about 13% and 6% respectively. The increase in the Pe number by 100% results in a rise in the temperature distribution by 8%.","PeriodicalId":9736,"journal":{"name":"CFD Letters","volume":"48 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140080473","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}
The impact of Joule heating for the three-dimensional stagnation point flow of non-Newtonian liquid (namely Oldroyd-B) nanomaterial has been inspected. The influence of mixed convection and the magnetic force is also considered. The flow is induced by the bidirectional stretched surface which moves linearly. The partial differential equations for the developed model are altered into dimensionless statements first. The numerical simulations with the implementation of a finite difference scheme are used for the numerical description. The physical description of parameters is presented against the flow parameters. The results reveal that there is a reverse change in velocity observed for both the relaxation time constant and the retardation constant. Furthermore, the heat transfer rate decreases as the ratio parameter increases. The thickness of the boundary layer increases due to the retardation time and can also be regulated by the application of a magnetic field. An increase in the magnetic parameter leads to an enhancement in temperature and an increase in thermal boundary layer thickness.
{"title":"Bi-directional Forced Convective Stagnation Points Flow of Oldroyd-B Liquid with Joule Heating Effects: A Finite Difference Simulations","authors":"Bilal Ahmed","doi":"10.37934/cfdl.16.7.2238","DOIUrl":"https://doi.org/10.37934/cfdl.16.7.2238","url":null,"abstract":"The impact of Joule heating for the three-dimensional stagnation point flow of non-Newtonian liquid (namely Oldroyd-B) nanomaterial has been inspected. The influence of mixed convection and the magnetic force is also considered. The flow is induced by the bidirectional stretched surface which moves linearly. The partial differential equations for the developed model are altered into dimensionless statements first. The numerical simulations with the implementation of a finite difference scheme are used for the numerical description. The physical description of parameters is presented against the flow parameters. The results reveal that there is a reverse change in velocity observed for both the relaxation time constant and the retardation constant. Furthermore, the heat transfer rate decreases as the ratio parameter increases. The thickness of the boundary layer increases due to the retardation time and can also be regulated by the application of a magnetic field. An increase in the magnetic parameter leads to an enhancement in temperature and an increase in thermal boundary layer thickness.","PeriodicalId":9736,"journal":{"name":"CFD Letters","volume":"12 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140266192","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}
Obulesu Mopuri, A.Sailakumari, Aruna Ganjikunta, Sudhakara E, VenkateswaraRaju K, Ramesh P, Charankumar Ganteda, B.Ramakrishna Reddy, S. V. K. Varma
This paper is concerned with the study of an unsteady, MHD natural convective boundary layer flow of a viscous, incompressible and electrically conducting, non-Newtonian Jeffery fluid over a semi-infinite vertically inclined permeable moving plate embedded in a porous medium in the presence of thermal radiation, heat absorption and thermal diffusion, heat and mass transfer. . The permeability of the porous medium and the suction velocity are considered to be an exponentially decreasing function of time. The fundamental governing equations for this investigation are solved numerically using the perturbation technique. The results are presented graphically and in tabular form for various controlling parameters. The behavior of different physical parameters is shown graphically. The numerical values of Skin friction, Nusselt number, and Sherwood number are presented in a tabular form. Obtained outcomes are compared with earlier studies in the special case and strong agreement is noted. From graphical representation, it is concluded that velocity and temperature distribution increases with the mixed convection parameter and buoyancy force parameter. An increasing value of magnetic field parameter, slip parameter, and Jeffery parameter tends to reduced velocity and also raising the values of Prandtl number, radiation parameter and heat absorption parameter tends to downfallen temperature profiles. This study may be useful in several industrial applications, for example, polymer production, manufacturing of ceramics or glassware and food processing, and so forth.
{"title":"Characteristics of MHD Jeffery Fluid Past an Inclined Vertical Porous Plate","authors":"Obulesu Mopuri, A.Sailakumari, Aruna Ganjikunta, Sudhakara E, VenkateswaraRaju K, Ramesh P, Charankumar Ganteda, B.Ramakrishna Reddy, S. V. K. Varma","doi":"10.37934/cfdl.16.6.6889","DOIUrl":"https://doi.org/10.37934/cfdl.16.6.6889","url":null,"abstract":"This paper is concerned with the study of an unsteady, MHD natural convective boundary layer flow of a viscous, incompressible and electrically conducting, non-Newtonian Jeffery fluid over a semi-infinite vertically inclined permeable moving plate embedded in a porous medium in the presence of thermal radiation, heat absorption and thermal diffusion, heat and mass transfer. . The permeability of the porous medium and the suction velocity are considered to be an exponentially decreasing function of time. The fundamental governing equations for this investigation are solved numerically using the perturbation technique. The results are presented graphically and in tabular form for various controlling parameters. The behavior of different physical parameters is shown graphically. The numerical values of Skin friction, Nusselt number, and Sherwood number are presented in a tabular form. Obtained outcomes are compared with earlier studies in the special case and strong agreement is noted. From graphical representation, it is concluded that velocity and temperature distribution increases with the mixed convection parameter and buoyancy force parameter. An increasing value of magnetic field parameter, slip parameter, and Jeffery parameter tends to reduced velocity and also raising the values of Prandtl number, radiation parameter and heat absorption parameter tends to downfallen temperature profiles. This study may be useful in several industrial applications, for example, polymer production, manufacturing of ceramics or glassware and food processing, and so forth.","PeriodicalId":9736,"journal":{"name":"CFD Letters","volume":"132 20","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139605236","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}
This article presents a numerical simulation of high hydrogen/air flames using the Lagrangian transported PDF method. This method enables the calculation of fluid composition changes resulting from convection and reaction without the need for modelling, while requiring modelling for molecular mixing. Consequently, the accuracy of calculations in this L-PDF method heavily relies on an accurate representation of the mixture model term. The Euclidean model, which provides a better description of physical mixing processes, is well-suited for modelling the molecular mixing term EMST. Additionally, the accuracy of this model depends on the value of the mixing constant, representing the ratio between the mechanical time scale and the scalar time scale. Two algebraic models for the mixing constant have been implemented in the computational code, employing a well-defined function to calculate this ratio for each cell. These models contribute to memory and CPU time savings. To account for turbulence and its interaction with physical phenomena, the RSM model is employed due to its ability to identify different areas of turbulent stresses. Hence, the primary objective of this study is to evaluate the capabilities of these algebraic models in predicting scalar fields within such flames. Overall, the predictions align well with experimental data, affirming the validity of these models.
本文采用拉格朗日传输 PDF 方法对高氢气/空气火焰进行了数值模拟。该方法无需建模即可计算对流和反应引起的流体成分变化,而分子混合则需要建模。因此,这种 L-PDF 方法的计算精度在很大程度上取决于混合模型项的准确表示。欧氏模型能更好地描述物理混合过程,非常适合建立分子混合项 EMST 模型。此外,该模型的准确性还取决于混合常数的值,它代表了机械时间尺度和标量时间尺度之间的比率。混合常数的两个代数模型已在计算代码中实施,采用一个定义明确的函数来计算每个单元的这一比率。这些模型有助于节省内存和 CPU 时间。为了解释湍流及其与物理现象的相互作用,采用了 RSM 模型,因为该模型能够识别湍流应力的不同区域。因此,本研究的主要目的是评估这些代数模型预测此类火焰中标量场的能力。总体而言,预测结果与实验数据非常吻合,从而肯定了这些模型的有效性。
{"title":"Investigation of Modified EMST Micromixing Model Performance on Lagrangian PDF Transported in Lifted Hydrogen/Air Fames","authors":"Mohamed Senouci, Ahmed Amine Larbi, Habib Rouan Serik, Abdehamid Bounif, Habib Merouane","doi":"10.37934/cfdl.16.6.2031","DOIUrl":"https://doi.org/10.37934/cfdl.16.6.2031","url":null,"abstract":"This article presents a numerical simulation of high hydrogen/air flames using the Lagrangian transported PDF method. This method enables the calculation of fluid composition changes resulting from convection and reaction without the need for modelling, while requiring modelling for molecular mixing. Consequently, the accuracy of calculations in this L-PDF method heavily relies on an accurate representation of the mixture model term. The Euclidean model, which provides a better description of physical mixing processes, is well-suited for modelling the molecular mixing term EMST. Additionally, the accuracy of this model depends on the value of the mixing constant, representing the ratio between the mechanical time scale and the scalar time scale. Two algebraic models for the mixing constant have been implemented in the computational code, employing a well-defined function to calculate this ratio for each cell. These models contribute to memory and CPU time savings. To account for turbulence and its interaction with physical phenomena, the RSM model is employed due to its ability to identify different areas of turbulent stresses. Hence, the primary objective of this study is to evaluate the capabilities of these algebraic models in predicting scalar fields within such flames. Overall, the predictions align well with experimental data, affirming the validity of these models.","PeriodicalId":9736,"journal":{"name":"CFD Letters","volume":"143 15","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139604460","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}
This work investigates the MHD flow of a Jeffery nanofluid through a non-linear stretching sheet, considering melting heat transfer and the combined influences of concentration and thermal radiation. A variable magnetic effect normal to the flow direction is enforced to reinforce the conductivity of the Jeffery nanofluid. The governing non-linear PDEs with convective boundary conditions are transformed into the non-dimensional ODEs, and we apply appropriate similarity variables. The further similarity transformation is determined with the 4th-order Runge-Kutta shooting technique facilitated. The approach is implemented for convergent relations of the rate field, temperature, and nano-particle concentration. However, small magnetic Reynolds is considered to decline the induced magnetic impact. Melting parameter enhances temperature and concentration. Finally, the effect of fluid parameters such as thermophoresis, melting parameter, Deborah number, chemical reaction, Brownian motion, inertia parameter, Darcy number, and thermophoresis on the MHD flow profiles is examined graphically.
{"title":"MHD Flow Darcy Forchheimeter of Jeffrey Nanofluid over a Stretching Sheet Considering Melting Heat Transfer and Viscous Dissipation heat transfe","authors":"Naresh Kumar, Gandrakota Srinivasu, Balagnoor Srikantha setty, Mani Ramanuja","doi":"10.37934/cfdl.16.6.131145","DOIUrl":"https://doi.org/10.37934/cfdl.16.6.131145","url":null,"abstract":"This work investigates the MHD flow of a Jeffery nanofluid through a non-linear stretching sheet, considering melting heat transfer and the combined influences of concentration and thermal radiation. A variable magnetic effect normal to the flow direction is enforced to reinforce the conductivity of the Jeffery nanofluid. The governing non-linear PDEs with convective boundary conditions are transformed into the non-dimensional ODEs, and we apply appropriate similarity variables. The further similarity transformation is determined with the 4th-order Runge-Kutta shooting technique facilitated. The approach is implemented for convergent relations of the rate field, temperature, and nano-particle concentration. However, small magnetic Reynolds is considered to decline the induced magnetic impact. Melting parameter enhances temperature and concentration. Finally, the effect of fluid parameters such as thermophoresis, melting parameter, Deborah number, chemical reaction, Brownian motion, inertia parameter, Darcy number, and thermophoresis on the MHD flow profiles is examined graphically.","PeriodicalId":9736,"journal":{"name":"CFD Letters","volume":"119 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139605509","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 : 2024-01-23DOI: 10.37934/cfdl.16.6.109119
Jorge Alvarez, Jonathan Fabregas Villegas, Mauricio Márquez, Javier Carpintero
Renewable energy sources derived from biomass, such as synthesis gases, represent an opportunity to take advantage of available waste resources and contribute to global energy rationing. This study developed an analysis with computational fluid dynamics (CFD) to estimate the energy behavior of synthesis gases through a turbocharger system. The synthesis gas used to drive the turbocharger turbine was extracted from the gasification of biomass from the Colombian Caribbean. The application of models for rigid body motion, as well as models of momentum, turbulence, energy, and conservation transport of species, suggest that the energy potential available by the turbine ranges from 0.4 kW to 5.2 kW of power generation, concerning mass flow rates entering the simulated system. The main findings of the study were temperature profiles, speed profiles, rotational speed variation, torque, and mechanical power generated in the turbocharger. It is emphasized that the synthesis gas studied presents a good behavior to generate energy through a turbine system of a turbocharger device.
{"title":"Energy Evaluation of Synthesis Gas in a Turbocharger System Employing CFD Tools","authors":"Jorge Alvarez, Jonathan Fabregas Villegas, Mauricio Márquez, Javier Carpintero","doi":"10.37934/cfdl.16.6.109119","DOIUrl":"https://doi.org/10.37934/cfdl.16.6.109119","url":null,"abstract":"Renewable energy sources derived from biomass, such as synthesis gases, represent an opportunity to take advantage of available waste resources and contribute to global energy rationing. This study developed an analysis with computational fluid dynamics (CFD) to estimate the energy behavior of synthesis gases through a turbocharger system. The synthesis gas used to drive the turbocharger turbine was extracted from the gasification of biomass from the Colombian Caribbean. The application of models for rigid body motion, as well as models of momentum, turbulence, energy, and conservation transport of species, suggest that the energy potential available by the turbine ranges from 0.4 kW to 5.2 kW of power generation, concerning mass flow rates entering the simulated system. The main findings of the study were temperature profiles, speed profiles, rotational speed variation, torque, and mechanical power generated in the turbocharger. It is emphasized that the synthesis gas studied presents a good behavior to generate energy through a turbine system of a turbocharger device.","PeriodicalId":9736,"journal":{"name":"CFD Letters","volume":"41 24","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139603630","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}
During the COVID-19 pandemic, data statistics showed that patients with respiratory problems become infected. One of the therapy techniques for the respiratory condition was the use of a metered-dose inhaler and spacer. The objective of this paper is to determine the flow parameters of three types of valves which is duckbill valve, cross slit valve and umbrella valve in inhaler spacer to compare fluid flow between valve Previous researchers chose the duckbill valve to control fluid flow in inhaler spacer. The flow characteristics are unaffected by the materials used in the new disposable inhaler spacers, such as paper and polylactic acid (PLA). Several design valves reduced the skewness below 0.94 by suppressing the fillet and chamfer. ANSYS Workbench Fluent 19.2 is used to calculate flow parameters such as turbulence kinetic energy (TKE), turbulence eddy dissipation (TED), velocity, particle velocity magnitude, streamline, and vector velocity. The setup input data is based on the previous researcher's specified parameters such as viscosity model, drug characteristics (salbutamol and propellant), discrete phase model (DPM) equal to 80, boundary condition model, and SIMPLE technique. For the three types of valves, the nozzle injection used a 0.50-millimetre dimension. The simulation work is cross-checked against the results of prior simulations. Within each iteration, the transient flow employed a time step size of 0.01 for 200 steps. The results show that computational analysis can distinguish between models of varying complexity. The TED, TKE, and velocity graphs showed the approximate value between the model geometries. Overall, the study was successful in achieving the desired velocity magnitude in terms of visual and graph representations of the various valve.
{"title":"CFD Analysis for Valve-Holding Camber Permanent Inhaler Spacer (AerospaAcer) with Different Valves","authors":"Riyadhthusollehan Khairulfuaad, Norzelawati Asmuin, Juntakan Taweekun, Azizan Ismail, Nabil Izzuddin Shahhidan","doi":"10.37934/cfdl.16.6.5367","DOIUrl":"https://doi.org/10.37934/cfdl.16.6.5367","url":null,"abstract":"During the COVID-19 pandemic, data statistics showed that patients with respiratory problems become infected. One of the therapy techniques for the respiratory condition was the use of a metered-dose inhaler and spacer. The objective of this paper is to determine the flow parameters of three types of valves which is duckbill valve, cross slit valve and umbrella valve in inhaler spacer to compare fluid flow between valve Previous researchers chose the duckbill valve to control fluid flow in inhaler spacer. The flow characteristics are unaffected by the materials used in the new disposable inhaler spacers, such as paper and polylactic acid (PLA). Several design valves reduced the skewness below 0.94 by suppressing the fillet and chamfer. ANSYS Workbench Fluent 19.2 is used to calculate flow parameters such as turbulence kinetic energy (TKE), turbulence eddy dissipation (TED), velocity, particle velocity magnitude, streamline, and vector velocity. The setup input data is based on the previous researcher's specified parameters such as viscosity model, drug characteristics (salbutamol and propellant), discrete phase model (DPM) equal to 80, boundary condition model, and SIMPLE technique. For the three types of valves, the nozzle injection used a 0.50-millimetre dimension. The simulation work is cross-checked against the results of prior simulations. Within each iteration, the transient flow employed a time step size of 0.01 for 200 steps. The results show that computational analysis can distinguish between models of varying complexity. The TED, TKE, and velocity graphs showed the approximate value between the model geometries. Overall, the study was successful in achieving the desired velocity magnitude in terms of visual and graph representations of the various valve.","PeriodicalId":9736,"journal":{"name":"CFD Letters","volume":"111 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139606067","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}
The depletion of fossil fuels and environmental considerations in transportation sector motivate the researchers to enhance the efficiency and performance of the automotive systems. However, the poor thermal performance of conventional coolant poses a limitation in the development of energy-efficient vehicle due to the cooling constraint. In the present study, a comprehensive numerical study is conducted to scrutinize the convective performance of graphene nanoplatelets (GnP) nanofluid in millimeter-sized automotive radiator, aiming to enhance the understandings on the underlying physical significance of the suspension of graphene-based nanoparticle in water for the performance enhancement of automotive radiator. The temperature-dependent thermophysical properties of GnP-water nanofluid is predicted via existing correlations, while a modified viscosity correlation is developed. ANSYS Fluent is employed in the present numerical simulation to investigate the effects of various pertinent parameters such as Reynolds number, nanoparticles aspect ratio, tube aspect ratio and tube hydraulic diameter on the heat transfer performance of the radiator. Double precision and second-order upwind scheme with inclusion of viscous heating, and convergent criteria of 10˗6 are adopted for the present simulation. It is observed that the convective performance of the radiator is significantly enhanced by increasing Reynolds number and nanoparticle volume fraction while decreasing the aspect ratios of nanoparticle and radiator tube, with an enhancement rate as much as 1816%. Therefore, it is evident that the suspension of GnP intensifies the heat transfer performance of millimeter-sized automotive radiator, which could possibly lead to a more efficient radiator that is smaller and lighter.
{"title":"Numerical Simulation of Graphene-Nanoplatelet Nanofluid Convection in Millimeter-Sized Automotive Radiator","authors":"Leslie Kok Lik Toh, Tiew Wei Ting","doi":"10.37934/cfdl.16.6.3252","DOIUrl":"https://doi.org/10.37934/cfdl.16.6.3252","url":null,"abstract":"The depletion of fossil fuels and environmental considerations in transportation sector motivate the researchers to enhance the efficiency and performance of the automotive systems. However, the poor thermal performance of conventional coolant poses a limitation in the development of energy-efficient vehicle due to the cooling constraint. In the present study, a comprehensive numerical study is conducted to scrutinize the convective performance of graphene nanoplatelets (GnP) nanofluid in millimeter-sized automotive radiator, aiming to enhance the understandings on the underlying physical significance of the suspension of graphene-based nanoparticle in water for the performance enhancement of automotive radiator. The temperature-dependent thermophysical properties of GnP-water nanofluid is predicted via existing correlations, while a modified viscosity correlation is developed. ANSYS Fluent is employed in the present numerical simulation to investigate the effects of various pertinent parameters such as Reynolds number, nanoparticles aspect ratio, tube aspect ratio and tube hydraulic diameter on the heat transfer performance of the radiator. Double precision and second-order upwind scheme with inclusion of viscous heating, and convergent criteria of 10˗6 are adopted for the present simulation. It is observed that the convective performance of the radiator is significantly enhanced by increasing Reynolds number and nanoparticle volume fraction while decreasing the aspect ratios of nanoparticle and radiator tube, with an enhancement rate as much as 1816%. Therefore, it is evident that the suspension of GnP intensifies the heat transfer performance of millimeter-sized automotive radiator, which could possibly lead to a more efficient radiator that is smaller and lighter.","PeriodicalId":9736,"journal":{"name":"CFD Letters","volume":"14 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139604166","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}