首页 > 最新文献

Heat Transfer Research最新文献

英文 中文
Validating the First Law of Thermodynamics for Unsteady Flow in a Compression Wave Using Mathcad 用Mathcad验证压缩波非定常流动热力学第一定律
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-11-01 DOI: 10.1615/heattransres.2023051072
Vladimir Ryndin, Amangeldy Karmanov, Akmaral Kinzhibekova, Rizagul Dyussova, Gulnara Abdullina
Classical thermodynamics traditionally overlooks the role of quantities dependent on spatial coordinates and time, especially in the context of unsteady flows. This research introduces the first law of thermodynamics (FLT) tailored for non-stationary flow, distinguishing itself with the inclusion of terms bearing partial derivatives of pressure, p(x, t), concerning coordinates and time (–υ(∂р/∂х)dx; –υ(∂р/∂t)dt). By employing this novel approach, the derived equations are validated using a centred compression wave as a representative non-stationary flow case study. A methodology is also presented for experimentally quantifying hydrodynamic energy losses in the intake and exhaust systems of internal combustion engines. Central to the exploration is the calculation of pressure forces' work –υ(∂р/∂х)dx and –υ(∂р/∂t)dt) in the FLT equation for non-stationary flows, particularly their applicability to a centred compression wave. Moreover, a distinct procedure for discerning friction work in non-stationary flow is delineated. The research methods encompass both analytical derivation and numerical simulations leveraging Mathcad software. The bespoke Mathcad program crafted for this study can graphically represent multiple flow parameters as functions of time, proving invaluable for comprehending compression wave dynamics and evaluating friction work in diverse non-steady flows. Ultimately, the incorporation of energy equations tailored for non-stationary flows into classical thermodynamics paves the way for a more comprehensive understanding and application of thermodynamics to intricate flow scenarios.
经典热力学传统上忽略了依赖于空间坐标和时间的量的作用,特别是在非定常流动的情况下。本研究介绍了为非平稳流动量身定制的热力学第一定律(FLT),其区别在于包含包含压力偏导数的项,p(x, t),涉及坐标和时间(-υ(∂r /∂r)dx;υ(∂р/∂t) dt)。通过采用这种新方法,推导出的方程以中心压缩波为代表的非平稳流动案例研究进行了验证。本文还提出了一种实验量化内燃机进气和排气系统中流体动力能量损失的方法。探索的核心是计算非平稳流动的FLT方程中压力的功-υ(∂r /∂r)dx和-υ(∂r /∂t)dt),特别是它们对中心压缩波的适用性。此外,一个独特的程序来识别摩擦功在非平稳流动描述。研究方法包括分析推导和利用Mathcad软件的数值模拟。为这项研究量身定制的Mathcad程序可以用图形表示多种流动参数作为时间的函数,这对于理解压缩波动力学和评估各种非稳定流动中的摩擦功是非常宝贵的。最终,将非平稳流动的能量方程纳入经典热力学,为更全面地理解和应用热力学来解决复杂的流动问题铺平了道路。
{"title":"Validating the First Law of Thermodynamics for Unsteady Flow in a Compression Wave Using Mathcad","authors":"Vladimir Ryndin, Amangeldy Karmanov, Akmaral Kinzhibekova, Rizagul Dyussova, Gulnara Abdullina","doi":"10.1615/heattransres.2023051072","DOIUrl":"https://doi.org/10.1615/heattransres.2023051072","url":null,"abstract":"Classical thermodynamics traditionally overlooks the role of quantities dependent on spatial coordinates and time, especially in the context of unsteady flows. This research introduces the first law of thermodynamics (FLT) tailored for non-stationary flow, distinguishing itself with the inclusion of terms bearing partial derivatives of pressure, p(x, t), concerning coordinates and time (–υ(∂р/∂х)dx; –υ(∂р/∂t)dt). By employing this novel approach, the derived equations are validated using a centred compression wave as a representative non-stationary flow case study. A methodology is also presented for experimentally quantifying hydrodynamic energy losses in the intake and exhaust systems of internal combustion engines. Central to the exploration is the calculation of pressure forces' work –υ(∂р/∂х)dx and –υ(∂р/∂t)dt) in the FLT equation for non-stationary flows, particularly their applicability to a centred compression wave. Moreover, a distinct procedure for discerning friction work in non-stationary flow is delineated. The research methods encompass both analytical derivation and numerical simulations leveraging Mathcad software. The bespoke Mathcad program crafted for this study can graphically represent multiple flow parameters as functions of time, proving invaluable for comprehending compression wave dynamics and evaluating friction work in diverse non-steady flows. Ultimately, the incorporation of energy equations tailored for non-stationary flows into classical thermodynamics paves the way for a more comprehensive understanding and application of thermodynamics to intricate flow scenarios.","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"7 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138536144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Effect of radiation absorption and chemical reaction on MHD‐free convective flow through a porous medium past an infinite vertical porous plate in the presence of constant heat flux 恒定热通量下辐射吸收和化学反应对多孔介质中无MHD对流的影响
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-08-17 DOI: 10.1002/htj.22936
N. Ahmed, Richa Deb Dowerah
An incompressible, electrically conducting, and viscous fluid flowing steadily and freely across a uniformly porous media that is partially constrained by an infinitely long vertical porous plate is studied in the present article. Additionally, chemical reaction and radiation absorption effects are seen. Here, a magnetic field of uniform strength is applied transversely to the plate, a normal suction velocity is imposed on the fluid, and the heat flux is considered to be constant. The non‐dimensional momentum and energy equations are solved using the method of perturbation. The problem has been analytically resolved, and several parameters, including the Hartmann number, porosity parameter, thermal Grashof number, mass Grashof number, and transport properties like the Sherwood number, skin friction, and plate temperature, are graphically represented. The current study reveals a spike in the radiation absorption effect causes skin friction to drop, but on the other hand, a contrary effect is observed for plate temperature. One of the notable findings of this investigation is that the Sherwood number increases as chemical reaction parameter influence increases.
本文研究了一种不可压缩的、导电的粘性流体稳定自由地流过均匀多孔介质,该介质部分受无限长垂直多孔板的约束。此外,还观察到化学反应和辐射吸收效应。在这里,在板的横向上施加均匀强度的磁场,对流体施加正常的吸力速度,并且认为热流密度是恒定的。用摄动法求解了非量纲动量方程和能量方程。这一问题已经得到了解析解决,包括Hartmann数、孔隙度参数、热Grashof数、质量Grashof数以及Sherwood数、表面摩擦和板温等输运性质在内的几个参数都用图形表示了出来。目前的研究表明,辐射吸收效应的峰值会导致皮肤摩擦下降,但另一方面,对板温观察到相反的效果。本研究的一个显著发现是舍伍德数随化学反应参数影响的增加而增加。
{"title":"Effect of radiation absorption and chemical reaction on MHD‐free convective flow through a porous medium past an infinite vertical porous plate in the presence of constant heat flux","authors":"N. Ahmed, Richa Deb Dowerah","doi":"10.1002/htj.22936","DOIUrl":"https://doi.org/10.1002/htj.22936","url":null,"abstract":"An incompressible, electrically conducting, and viscous fluid flowing steadily and freely across a uniformly porous media that is partially constrained by an infinitely long vertical porous plate is studied in the present article. Additionally, chemical reaction and radiation absorption effects are seen. Here, a magnetic field of uniform strength is applied transversely to the plate, a normal suction velocity is imposed on the fluid, and the heat flux is considered to be constant. The non‐dimensional momentum and energy equations are solved using the method of perturbation. The problem has been analytically resolved, and several parameters, including the Hartmann number, porosity parameter, thermal Grashof number, mass Grashof number, and transport properties like the Sherwood number, skin friction, and plate temperature, are graphically represented. The current study reveals a spike in the radiation absorption effect causes skin friction to drop, but on the other hand, a contrary effect is observed for plate temperature. One of the notable findings of this investigation is that the Sherwood number increases as chemical reaction parameter influence increases.","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"160 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74154423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Study of weakly nonlinear double‐diffusive magnetoconvection under concentration modulation 浓度调制下弱非线性双扩散磁对流的研究
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-08-16 DOI: 10.1002/htj.22939
Atul Jakhar, Anand Kumar, Vinod K. Gupta
This article explains the heat and mass transfer of electrically conducting Newtonian fluid in double‐diffusive magnetoconvective flow. We have considered two infinite horizontal plates at a constant distance apart under the concentration‐modulated boundary condition. A constant magnetic field is considered in vertically upward directions, which generates an induced magnetic field. We have used the weakly nonlinear analysis to obtain the heat and mass transfer rate using the Ginzburg–Landau equation. The software MATHEMATICA is used to determine the solution of the Ginzburg–Landau equation by inbuilt function. The effects of physical parameters that occurred in the study on the Nusselt number and Sherwood number have been examined graphically. Modulation has a negligible effect on the threshold value of the thermal Rayleigh number, that is, on stationary convection. Moreover, it was found that the Chandrasekhar number, magnetic‐Prandtl number, amplitude of modulation, and frequency of modulation are proportional to the heat and mass transports.
本文解释了双扩散磁对流中导电牛顿流体的传热传质。在浓度调制边界条件下,我们考虑了两个距离恒定的无限大水平板。考虑垂直向上的恒定磁场,产生感应磁场。本文采用弱非线性分析方法,利用金兹堡-朗道方程求出了传热传质速率。利用MATHEMATICA软件通过内置函数确定了金兹堡-朗道方程的解。对研究中出现的物理参数对努塞尔数和舍伍德数的影响进行了图解检验。调制对热瑞利数阈值的影响可以忽略不计,即对静止对流的影响。此外,还发现钱德拉塞卡数、磁普朗特数、调制幅度和调制频率与热输运和质量输运成正比。
{"title":"Study of weakly nonlinear double‐diffusive magnetoconvection under concentration modulation","authors":"Atul Jakhar, Anand Kumar, Vinod K. Gupta","doi":"10.1002/htj.22939","DOIUrl":"https://doi.org/10.1002/htj.22939","url":null,"abstract":"This article explains the heat and mass transfer of electrically conducting Newtonian fluid in double‐diffusive magnetoconvective flow. We have considered two infinite horizontal plates at a constant distance apart under the concentration‐modulated boundary condition. A constant magnetic field is considered in vertically upward directions, which generates an induced magnetic field. We have used the weakly nonlinear analysis to obtain the heat and mass transfer rate using the Ginzburg–Landau equation. The software MATHEMATICA is used to determine the solution of the Ginzburg–Landau equation by inbuilt function. The effects of physical parameters that occurred in the study on the Nusselt number and Sherwood number have been examined graphically. Modulation has a negligible effect on the threshold value of the thermal Rayleigh number, that is, on stationary convection. Moreover, it was found that the Chandrasekhar number, magnetic‐Prandtl number, amplitude of modulation, and frequency of modulation are proportional to the heat and mass transports.","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"36 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82028310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Numerical investigation of the shell configuration effect on the melting of various phase change materials in the presence of porous medium and non‐Newtonian fluid 多孔介质和非牛顿流体存在时壳型对不同相变材料熔化影响的数值研究
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-08-14 DOI: 10.1002/htj.22938
Touraj Azarbarzin, K. Javaherdeh
By considering the ability of phase change materials (PCMs) in the storage of energy, the melting of four types PCMs including RT22, RT26, RT35, and RT41 in a heat exchanger is examined in this research. The impact of various shell cross‐sectional configurations on the complete melting time of materials, temperature changes, and liquid fraction throughout the melting process are presented. It is assumed that the main heat transfer fluid in the tube is non‐Newtonian and the tube is filled with a porous medium. The enthalpy porosity manner is applied for simulating the process of phase change and the heat natural convection and conduction cases are discussed. On the basis of the obtained results, the decrease in complete melting time is about 20% compared with the absence of a porous medium in the circular cross‐section configuration. The shell configuration has a noticeable impact on the reduction of the required time for melting. In the square cross‐section configuration, RT22 has the lowest melting time, as well as RT41 has the longest melting time in the inverted triangular cross‐section configuration in which the maximum time difference for RT22 is about 77% less. So, the best cross‐section for the shortest complete melting time is square.
考虑相变材料的储能能力,研究了RT22、RT26、RT35和RT41四种相变材料在换热器中的熔化情况。在整个熔化过程中,给出了不同壳截面构型对材料完全熔化时间、温度变化和液体分数的影响。假设管内的主要传热流体为非牛顿流体,管内充满多孔介质。采用焓孔法模拟相变过程,讨论了热自然对流和导热情况。根据得到的结果,与在圆形截面结构中不含多孔介质相比,完全熔化时间减少了约20%。壳体结构对减少所需的熔化时间有显著的影响。在方形截面结构中,RT22的熔化时间最短,而在倒三角形截面结构中,RT41的熔化时间最长,其中RT22的最大时间差约小77%。因此,最短完全熔化时间的最佳截面为方形。
{"title":"Numerical investigation of the shell configuration effect on the melting of various phase change materials in the presence of porous medium and non‐Newtonian fluid","authors":"Touraj Azarbarzin, K. Javaherdeh","doi":"10.1002/htj.22938","DOIUrl":"https://doi.org/10.1002/htj.22938","url":null,"abstract":"By considering the ability of phase change materials (PCMs) in the storage of energy, the melting of four types PCMs including RT22, RT26, RT35, and RT41 in a heat exchanger is examined in this research. The impact of various shell cross‐sectional configurations on the complete melting time of materials, temperature changes, and liquid fraction throughout the melting process are presented. It is assumed that the main heat transfer fluid in the tube is non‐Newtonian and the tube is filled with a porous medium. The enthalpy porosity manner is applied for simulating the process of phase change and the heat natural convection and conduction cases are discussed. On the basis of the obtained results, the decrease in complete melting time is about 20% compared with the absence of a porous medium in the circular cross‐section configuration. The shell configuration has a noticeable impact on the reduction of the required time for melting. In the square cross‐section configuration, RT22 has the lowest melting time, as well as RT41 has the longest melting time in the inverted triangular cross‐section configuration in which the maximum time difference for RT22 is about 77% less. So, the best cross‐section for the shortest complete melting time is square.","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74112524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Constructal design of vertical multiscale triangular fins in natural convection 自然对流中垂直多尺度三角翅片结构设计
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-08-14 DOI: 10.1002/htj.22935
A. Mustafa, H. S. Hasan, Hadeel Hamid Khlaif
Constructal design of vertical multiscale triangular fins in natural convection is investigated in this paper. The design consists of two parts. The first part is for single‐scale triangular fins. The objective in the first design is to reach to the highest heat transfer density from the fins for three fin angles (15°, 30°, and 45°). The single‐scale fins are placed in a horizontal array and considered as isothermal fins. The degrees of freedom are the fin angle, and the fin‐to‐fin spacing. The constraint is the fin height. The second part is for multiscale fins where small fins are placed between the large fins which are optimized in the first part. In the second part, the angles of the large and small scales fins are kept constant at (15°). The optimal fin‐to‐fin spacing which is obtained in the first part is considered a constraint in the second part. The Rayleigh numbers in this design are (Ra = 103, 104, and 105). The two‐dimensional mass, momentum, and energy equations for natural convection are solved with the finite volume method. The results show that there is a benefit of placing the small‐scale fins where the percentage increase in the heat transfer density is (10.22%) at (Ra = 103), and (50.6%) at (Ra = 105) due to existence of the small fins between the large fins.
研究了自然对流条件下垂直多尺度三角翅片的结构设计。本设计由两部分组成。第一部分适用于单尺度三角形鳍片。第一个设计的目标是在三个翅片角度(15°,30°和45°)下达到最高的传热密度。单尺度翅片被放置在一个水平阵列中,被认为是等温翅片。自由度是鳍角和鳍与鳍之间的间距。约束条件是鳍的高度。第二部分是多尺度鳍片,其中小鳍片放置在第一部分优化的大鳍片之间。在第二部分中,大小鳞鳍的角度保持恒定在(15°)。在第一部分中获得的最佳鳍对鳍间距被认为是第二部分的约束。本设计的瑞利数为(Ra = 103, 104, 105)。用有限体积法求解了自然对流的二维质量、动量和能量方程。结果表明,在(Ra = 103)和(Ra = 105)处,由于在大翅片之间存在小翅片,小翅片的传热密度增加百分比分别为10.22%和50.6%。
{"title":"Constructal design of vertical multiscale triangular fins in natural convection","authors":"A. Mustafa, H. S. Hasan, Hadeel Hamid Khlaif","doi":"10.1002/htj.22935","DOIUrl":"https://doi.org/10.1002/htj.22935","url":null,"abstract":"Constructal design of vertical multiscale triangular fins in natural convection is investigated in this paper. The design consists of two parts. The first part is for single‐scale triangular fins. The objective in the first design is to reach to the highest heat transfer density from the fins for three fin angles (15°, 30°, and 45°). The single‐scale fins are placed in a horizontal array and considered as isothermal fins. The degrees of freedom are the fin angle, and the fin‐to‐fin spacing. The constraint is the fin height. The second part is for multiscale fins where small fins are placed between the large fins which are optimized in the first part. In the second part, the angles of the large and small scales fins are kept constant at (15°). The optimal fin‐to‐fin spacing which is obtained in the first part is considered a constraint in the second part. The Rayleigh numbers in this design are (Ra = 103, 104, and 105). The two‐dimensional mass, momentum, and energy equations for natural convection are solved with the finite volume method. The results show that there is a benefit of placing the small‐scale fins where the percentage increase in the heat transfer density is (10.22%) at (Ra = 103), and (50.6%) at (Ra = 105) due to existence of the small fins between the large fins.","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"22 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81487446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Heat transfer characteristics in non‐Newtonian fluid flow due to a naturally permeable curved surface and chemical reaction 非牛顿流体流动中由于自然可渗透曲面和化学反应的传热特性
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-08-09 DOI: 10.1002/htj.22934
A. Olkha, Mukesh Kumar
In this research endeavor, Casson fluid flow and melting heat transfer due to a curved nonlinearly stretching sheet are investigated. The sheet is naturally permeable and the flow is considered in a porous medium. For flow in a porous medium, a modified Darcy's resistance term for Casson fluid is considered in the momentum equation. In the energy equation, heat transport characteristics, including viscous dissipation, are taken into account. Mass transport is also studied together with the impact of chemical reaction of higher order. The governing nonlinear partial differential equations of flow, heat, and mass transport are reduced to nondimensional ordinary differential equations using adequate similarity transformations and then solved numerically employing the bvp4c technique and Runge–Kutta fourth‐order method on MATLAB. The impacts of numerous occurring parameters on relevant fields (velocity field, temperature field, and concentration field) are depicted and discussed by plotting graphs. We concluded the curvature parameter, reduces the pace of the flow. The impacts of the stretching index, and melting parameter, are also found to reduce flow and temperature field. Furthermore, we noted that the reaction parameter, and its order, exhibit opposite impacts on the concentration field. Moreover, the numerical values of skin‐friction coefficient and Nusselt number calculated employing bvp4c and Runge–Kutta fourth‐order technique are expressed in tabular mode, and these are found in an excellent match. For validation of the results, skin‐friction coefficient values were computed using the Runge–Kutta fourth‐order technique and bvp4c solver, compared with the existing results, and a good agreement was found.
在本研究中,研究了卡森流体在弯曲非线性拉伸下的流动和熔化换热。薄片是自然可渗透的,流动被认为是在多孔介质中。对于多孔介质的流动,在动量方程中考虑了卡森流体的修正达西阻力项。在能量方程中,考虑了热传递特性,包括粘性耗散。还研究了质量输运以及高阶化学反应的影响。利用适当的相似变换,将控制流体、热量和质量传递的非线性偏微分方程简化为无维常微分方程,然后在MATLAB上采用bvp4c技术和龙格-库塔四阶方法进行数值求解。通过绘制图形,描述和讨论了许多发生参数对相关场(速度场、温度场和浓度场)的影响。我们得出曲率参数,减少了流动的速度。拉伸指数和熔化参数对流动场和温度场也有影响。此外,我们注意到反应参数及其顺序对浓度场的影响相反。此外,采用bvp4c和龙格-库塔四阶技术计算的表面摩擦系数和努塞尔数的数值以表格形式表示,两者具有很好的匹配性。为了验证结果,利用龙格-库塔四阶技术和bvp4c求解器计算了表面摩擦系数值,并与已有结果进行了比较,发现两者吻合较好。
{"title":"Heat transfer characteristics in non‐Newtonian fluid flow due to a naturally permeable curved surface and chemical reaction","authors":"A. Olkha, Mukesh Kumar","doi":"10.1002/htj.22934","DOIUrl":"https://doi.org/10.1002/htj.22934","url":null,"abstract":"In this research endeavor, Casson fluid flow and melting heat transfer due to a curved nonlinearly stretching sheet are investigated. The sheet is naturally permeable and the flow is considered in a porous medium. For flow in a porous medium, a modified Darcy's resistance term for Casson fluid is considered in the momentum equation. In the energy equation, heat transport characteristics, including viscous dissipation, are taken into account. Mass transport is also studied together with the impact of chemical reaction of higher order. The governing nonlinear partial differential equations of flow, heat, and mass transport are reduced to nondimensional ordinary differential equations using adequate similarity transformations and then solved numerically employing the bvp4c technique and Runge–Kutta fourth‐order method on MATLAB. The impacts of numerous occurring parameters on relevant fields (velocity field, temperature field, and concentration field) are depicted and discussed by plotting graphs. We concluded the curvature parameter, reduces the pace of the flow. The impacts of the stretching index, and melting parameter, are also found to reduce flow and temperature field. Furthermore, we noted that the reaction parameter, and its order, exhibit opposite impacts on the concentration field. Moreover, the numerical values of skin‐friction coefficient and Nusselt number calculated employing bvp4c and Runge–Kutta fourth‐order technique are expressed in tabular mode, and these are found in an excellent match. For validation of the results, skin‐friction coefficient values were computed using the Runge–Kutta fourth‐order technique and bvp4c solver, compared with the existing results, and a good agreement was found.","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"20 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89140798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Forced convective heat transfer for Stokes flow including viscous dissipation in arbitrary corrugated channels 斯托克斯流的强制对流换热,包括任意波纹通道中的粘性耗散
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-08-06 DOI: 10.1002/htj.22933
M. Shaimi, R. Khatyr, J. Naciri
The forced convective heat transfer for Stokes flow, including viscous dissipation in arbitrary corrugated channels, is studied using both an asymptotic method and a numerical solution. The aim is to specify the range of shape parameters for which the validity of the asymptotic approach is ensured, particularly regarding the characteristics of heat transfer. The axial velocity, transversal velocity, pressure, and temperature, for small corrugation's slope compared with unity, are sought as an asymptotic expansion in terms of a parameter that represents the corrugation's slope. The numerical solution is obtained by using ANSYS Fluent solver. Additionally, Python scripting is integrated to automate several parts of the simulations, including the creation of the geometry and a parametric study. Three different types of corrugations are investigated including zigzag, sinusoidal, and arbitrary corrugations defined using a function given by a particular case of the Fourier series. The Nusselt number is calculated to evaluate convective heat transfer. It is found that the asymptotic and numerical solutions for small corrugation's slope, are in good agreement with negligible quantitative differences. However, as the corrugation's slope increases (approaches unity), these quantitative differences increase up to cases where a change in the behavior of the local Nusselt number is observed. The results show that the local Nusselt number decreases in the channel's region with divergent walls due to the decrease in the average velocity. In contrast, it increases in the channel's region with convergent walls due to the increase in the average velocity.
采用渐近方法和数值方法研究了斯托克斯流的强迫对流换热问题,其中包括任意波纹通道中的粘性耗散。目的是指定形状参数的范围,以确保渐近方法的有效性,特别是关于传热的特性。轴向速度,横向速度,压力和温度,对于小波纹的斜率与统一,被寻求作为一个渐进展开的参数,表示波纹的斜率。利用ANSYS Fluent求解器进行了数值求解。此外,还集成了Python脚本来自动化模拟的几个部分,包括几何图形的创建和参数化研究。研究了三种不同类型的波纹,包括之字形,正弦和任意波纹,使用由傅里叶级数的特定情况给出的函数定义。计算努塞尔数来评估对流换热。结果表明,小波状边坡的渐近解和数值解符合得很好,数量上的差异可以忽略不计。然而,随着波纹的斜率增加(接近于一致),这些数量上的差异会增加,直到观察到局部努塞尔数的行为发生变化。结果表明,由于平均流速的减小,在具有发散壁面的通道区域局部努塞尔数减小。相比之下,由于平均速度的增加,在具有收敛壁面的通道区域,它会增加。
{"title":"Forced convective heat transfer for Stokes flow including viscous dissipation in arbitrary corrugated channels","authors":"M. Shaimi, R. Khatyr, J. Naciri","doi":"10.1002/htj.22933","DOIUrl":"https://doi.org/10.1002/htj.22933","url":null,"abstract":"The forced convective heat transfer for Stokes flow, including viscous dissipation in arbitrary corrugated channels, is studied using both an asymptotic method and a numerical solution. The aim is to specify the range of shape parameters for which the validity of the asymptotic approach is ensured, particularly regarding the characteristics of heat transfer. The axial velocity, transversal velocity, pressure, and temperature, for small corrugation's slope compared with unity, are sought as an asymptotic expansion in terms of a parameter that represents the corrugation's slope. The numerical solution is obtained by using ANSYS Fluent solver. Additionally, Python scripting is integrated to automate several parts of the simulations, including the creation of the geometry and a parametric study. Three different types of corrugations are investigated including zigzag, sinusoidal, and arbitrary corrugations defined using a function given by a particular case of the Fourier series. The Nusselt number is calculated to evaluate convective heat transfer. It is found that the asymptotic and numerical solutions for small corrugation's slope, are in good agreement with negligible quantitative differences. However, as the corrugation's slope increases (approaches unity), these quantitative differences increase up to cases where a change in the behavior of the local Nusselt number is observed. The results show that the local Nusselt number decreases in the channel's region with divergent walls due to the decrease in the average velocity. In contrast, it increases in the channel's region with convergent walls due to the increase in the average velocity.","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"56 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84602270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Numerical investigation of mixed convection of non‐Newtonian fluid in a vented square cavity with fixed baffle 非牛顿流体在带固定挡板的方形通风腔内混合对流的数值研究
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-08-02 DOI: 10.1002/htj.22932
Mohammed Abu Ghurban, Khaled Al-Farhany, O. Olayemi
This paper numerically investigates mixed convective heat transfer in a vented square cavity incorporated with a baffle that is subjected to external non‐Newtonian fluids (NNFs). Adiabatic conditions are imposed on the top and bottom walls, while cold temperature conditions are applied to the right and left solid boundaries. Heated NNF enters the cavity through the inlet and goes out through the outlet at three different locations, and it passes on a vertical baffle fixed at the base placed at different lengths. To examine the impact of the inlet and outlet positions, three different shapes of the outlet port located on the right wall and the inlet port on the left bottom wall were investigated. The impacts of Reynolds number (Re) of 100 ≤ Re ≤ 1000, Richardson number (Ri) of 0.1 ≤ Ri ≤ 3, power law index (n) of 0.6 ≤ n ≤ 1.4, length of baffle (Lb) of 0.2 ≤ Lb ≤ 0.6 and the outlet hole positions (S) of on the thermal and flow distributions in the cavity are taken into consideration in this paper. The results demonstrated that the flow's intensity and heat transfer increase with improvement in the Re and n at any baffle length. When the Ri increased from 0.1 to 3, increased by 23.3% at , and 13.8% at . Also, the Ri increment results in the augmentation of the average heat transfer.
本文数值研究了受外部非牛顿流体(NNFs)作用的带有挡板的方形通风腔内的混合对流换热。绝热条件施加于顶壁和底壁,而冷温度条件施加于左右固体边界。加热后的NNF通过入口进入空腔,并在三个不同的位置通过出口,并通过固定在底座上的垂直挡板,挡板的长度不同。为了检验进口和出口位置的影响,研究了三种不同形状的出口位于右壁和进口位于左底壁。本文考虑了雷诺数(Re)为100≤Re≤1000、理查德森数(Ri)为0.1≤Ri≤3、幂律指数(n)为0.6≤n≤1.4、挡板长度(Lb)为0.2≤Lb≤0.6和出口孔位置(S)对腔内热流分布的影响。结果表明,在任意挡板长度下,随着雷诺数和雷诺数的增加,流动强度和换热量均增加。当Ri由0.1增加到3时,at增加23.3%,at增加13.8%。同时,Ri的增加使平均换热量增大。
{"title":"Numerical investigation of mixed convection of non‐Newtonian fluid in a vented square cavity with fixed baffle","authors":"Mohammed Abu Ghurban, Khaled Al-Farhany, O. Olayemi","doi":"10.1002/htj.22932","DOIUrl":"https://doi.org/10.1002/htj.22932","url":null,"abstract":"This paper numerically investigates mixed convective heat transfer in a vented square cavity incorporated with a baffle that is subjected to external non‐Newtonian fluids (NNFs). Adiabatic conditions are imposed on the top and bottom walls, while cold temperature conditions are applied to the right and left solid boundaries. Heated NNF enters the cavity through the inlet and goes out through the outlet at three different locations, and it passes on a vertical baffle fixed at the base placed at different lengths. To examine the impact of the inlet and outlet positions, three different shapes of the outlet port located on the right wall and the inlet port on the left bottom wall were investigated. The impacts of Reynolds number (Re) of 100 ≤ Re ≤ 1000, Richardson number (Ri) of 0.1 ≤ Ri ≤ 3, power law index (n) of 0.6 ≤ n ≤ 1.4, length of baffle (Lb) of 0.2 ≤ Lb ≤ 0.6 and the outlet hole positions (S) of on the thermal and flow distributions in the cavity are taken into consideration in this paper. The results demonstrated that the flow's intensity and heat transfer increase with improvement in the Re and n at any baffle length. When the Ri increased from 0.1 to 3, increased by 23.3% at , and 13.8% at . Also, the Ri increment results in the augmentation of the average heat transfer.","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"3 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89593341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Investigation of Oldroyd‐B fluid flow and heat transfer over a stretching sheet with nonlinear radiation and heat source 具有非线性辐射和热源的拉伸板上Oldroyd - B流体流动和传热的研究
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-07-31 DOI: 10.1002/htj.22927
M. Goyal, Surbhi Sharma
{"title":"Investigation of Oldroyd‐B fluid flow and heat transfer over a stretching sheet with nonlinear radiation and heat source","authors":"M. Goyal, Surbhi Sharma","doi":"10.1002/htj.22927","DOIUrl":"https://doi.org/10.1002/htj.22927","url":null,"abstract":"","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"36 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85201424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Natural convection laminar flow between two vertical walls with a nonlinear variation of density and viscosity with temperature 两个垂直壁面之间的自然对流层流,密度和粘度随温度的非线性变化
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-07-27 DOI: 10.1002/htj.22931
H. Nagaraja, B. J. Gireesha
{"title":"Natural convection laminar flow between two vertical walls with a nonlinear variation of density and viscosity with temperature","authors":"H. Nagaraja, B. J. Gireesha","doi":"10.1002/htj.22931","DOIUrl":"https://doi.org/10.1002/htj.22931","url":null,"abstract":"","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"15 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73608803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
Heat Transfer Research
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1