Heat Transfer最新文献

{"title":"Bidirectional Stabilized Non-Newtonian Fluid Flow With Prescribed Heat Mechanism and Thermal Radiation in Stretching Sheet","authors":"Jyoti M.,&nbsp;Ashok Kumar Koti","doi":"10.1002/htj.23238","DOIUrl":"https://doi.org/10.1002/htj.23238","url":null,"abstract":"<div>\u0000 \u0000 <p>This study investigates the behavior of non-Newtonian fluid flow under magnetohydrodynamic (MHD) conditions, focusing on heat radiation effects during viscous flow over an elongated surface with penetrable boundaries. This research is important due to the increasing applications of non-Newtonian fluids in manufacturing and technical fields, necessitating advanced modeling techniques to accurately simulate their behavior under MHD conditions. To address the limitations of previous analyses that inadequately accounted for electrical field effects, we propose the Impetus Proliferate Method to enhance fluid flow velocity and establish better control over heat dissipation in practical devices like phase change thermal systems and power heat flux systems. The study employs the Novel Perpetuate Reconciliation Approach to manage heat transfer effectively within the elongated medium, revealing that heat transfer decreases as boundary layer thickness over the porous medium increases. Additionally, the Cogency Fortification Method significantly enhances the stability of non-Newtonian fluid flow over the extended sheet. The implementation of these methodologies in MATLAB Simulink provides a robust simulation framework, offering novel insights into the dynamic behavior of non-Newtonian fluids in MHD contexts and improving upon existing modeling techniques by integrating electrical field effects and deepening the understanding of heat transfer phenomena. Finally, the proposed model's accuracy is said to be 95%.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 3","pages":"1865-1887"},"PeriodicalIF":2.8,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the Feasibility of a Novel Solar Still With Fins, Phase Change Materials, and Wick Materials for Sustainable Water Production","authors":"Trinath Mahala,&nbsp;Naveen Sharma","doi":"10.1002/htj.23266","DOIUrl":"https://doi.org/10.1002/htj.23266","url":null,"abstract":"<div>\u0000 \u0000 <p>This work aims to enhance the performance of square pyramid solar stills, both conventional (CPSS) and modified (MPSS), by using wick materials, namely, black cotton cloth and jute cloth. The MPSS features fins and paraffin wax as the phase change material within the basin. The performance of solar stills (SSs) is evaluated through productivity, energy, exergy, economic, and environmental analyses, with sustainability assessed based on the energy production factor and energy payback period. The results confirm an improvement of about 43.08%, 30.77%, 29.23%, 17.89%, and 6.15% in daily yield for MPSS+C, MPSS+J, MPSS, CPSS+C, and CPSS+J, respectively, in comparison to CPSS. MPSS+C shows the maximum energy and exergy improvement of 45.82% and 177.2%, respectively. Energy production factors range from 1.87 to 4.79, with energy payback periods between 0.21 and 0.53 years across six cases. Interestingly, the MPSS+C shows a reduction in cost per liter in productivity and payback period of 10.1% each, in comparison to CPSS. The MPSS+C shows an increase in carbon credits of about 43%, while reducing the CO₂ emission of 3.27 tons. The results also proved that the productivity of SS using cotton is 12.31% higher than that of jute.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 3","pages":"1904-1920"},"PeriodicalIF":2.8,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing Minichannel Heat Sink Design: A Combined Numerical and Experimental Analysis of Inlet/Outlet Configurations and Pin Fin Enhancements","authors":"Hind Mahmood,&nbsp;Basim Freegah,&nbsp;Ahmad Muneer EL-Deen Faik,&nbsp;Qasim Saleh","doi":"10.1002/htj.23267","DOIUrl":"https://doi.org/10.1002/htj.23267","url":null,"abstract":"<div>\u0000 \u0000 <p>The present study investigated the effect of inlet location, counterflow and parallel flow configurations, and rib addition (pin fins) on the performance factor of minichannel heat sinks. Different rib spacings were investigated in Models D, E, and F, which are 5, 7, and 9 mm, respectively, all using counterflow. These models used ribs with a diameter of 1 mm. In addition, Models G and H were presented to explore different rib sizes (1.5 and 2 mm) while maintaining a rib spacing of 5 mm under counterflow conditions. All effects were studied numerically using ANSYS Fluent 19R3 under laminar coolant flow, with Reynolds numbers ranging from 1190 to 1900. The study also included fabricating two models: the conventional model and the optimized model, and comparing their results with the numerical results. The comparison indicated a satisfactory convergence between the experimental and numerical results. The results revealed that all modifications significantly improved the temperature distribution and overall performance factor (OPF). Model B outperformed the conventional model in terms of pressure drop and heat resistance, achieving improvements of 46% and 40%, respectively. Furthermore, Model D outperformed Model B in Nusselt number by 31.375%. Notably, Model D showed the highest OPF and most consistent core temperature among the models, confirming its status as the ideal design, with an OPF of 2 compared with the conventional model.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 3","pages":"1921-1939"},"PeriodicalIF":2.8,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stability Analysis of Gravity-Modulated Thermohaline Convection in Viscoelastic Fluid Saturating Porous Medium","authors":"Joginder Singh Dhiman,&nbsp;Khushboo Gupta,&nbsp;Praveen Kumar Sharma","doi":"10.1002/htj.23259","DOIUrl":"https://doi.org/10.1002/htj.23259","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper investigates the modified stability analysis of thermohaline convection in a horizontal Oldroyd-B fluid using the Darcy model, with applications in geophysics, environmental engineering, material science, and biological systems. The basic equations of motion and heat conduction in the present model are based on the Darcy model and the modified Boussinesq approximation. The perturbation equations are derived using the power series perturbation method to study two-dimensional convective roll instability with finite amplitude disturbances. Linear stability analysis, as a first-order stability problem, provides expressions for the Rayleigh numbers for stationary and oscillatory convection. The influence of various parameters, including the Darcy–Prandtl number, solutal Rayleigh number, stress and strain retardation parameters, and variations in the coefficient of specific heat, on the stability of the considered system, is studied numerically. It is observed that an approximate 67% increase in the coefficient of specific heat variations and a 23% increase in the solutal Rayleigh number result on average increases of 80% and 8%, respectively, in the value of the oscillatory Darcy–Rayleigh number. Conversely, an average 42% increase in the Darcy–Prandtl number leads to an average decrease of 8% in the oscillatory Darcy–Rayleigh number. In the weakly nonlinear oscillatory analysis, second- and third-order stability problems are discussed, and the Landau equation is derived, which describes the amplitudes of the convection cells. The effects of the parameters on heat and mass transfer rates, as described by the Nusselt and Sherwood numbers, are studied numerically. Furthermore, the weakly nonlinear stability analysis evaluates the effects of the Darcy–Prandtl number, specific heat coefficient, stress relaxation time, salinity Rayleigh number, strain retardation time, diffusivity ratio, and gravity modulation characteristics on heat and mass transfer rates. The effects of amplitude and frequency of gravity modulation on heat and mass transport are analyzed and depicted graphically. The study establishes that heat and mass transport can be effectively controlled by a mechanism external to the system. The results are validated by comparison with previous work, which considered a special case without the velocity gradient term in the momentum equation.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 3","pages":"1888-1903"},"PeriodicalIF":2.8,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Role of Periodic Mixing on Thermal Energy Extraction From an L-Shaped Heater Covered by Porous Layer","authors":"Nehila Tarek,&nbsp;Muneer Ismael","doi":"10.1002/htj.23265","DOIUrl":"https://doi.org/10.1002/htj.23265","url":null,"abstract":"<div>\u0000 \u0000 <p>In this numerical study, a technical solution is proposed to maximize heat transfer within a square cavity by integrating an L-shaped porous layer in the lower right part of the cavity, covering an L-shaped heat sink heated to a set temperature. Additionally, a thin bar undergoes a periodic sinusoidal motion with an amplitude of <i>V</i>_bar and a period of <i>ω</i>_bar. The finite element method is used to solve the governing dimensionless nonlinear equations, with a mesh test supported by numerical and experimental validations. The study focuses on the effects of bar displacement amplitude (<i>V</i>_bar = 0.1–0.4), displacement period (<i>ω</i>_bar = 1/3–1), Reynolds number (<i>Re</i> = 50, 100, and 200), Darcy number (<i>Da</i> = 10⁻² and 10⁻⁴), and porosity (<i>ε</i> = 0.75–0.95) on the average Nusselt number, streamlines, and isotherms distribution. The numerical results show that increasing the bar displacement amplitude, Darcy number, and Reynolds number can significantly enhance the overall heat transfer, while an increase in the porosity of the porous medium has the opposite effect. The bar's sinusoidal motion and the porous medium's presence alter the flow dynamics within the cavity and directly influence heat transfer.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 3","pages":"1851-1864"},"PeriodicalIF":2.8,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Study of Quadratic Buoyancy-Driven Magnetohydrodynamic Stagnation-Point Flow With Radiative Heat, Thermophoresis, and Arrhenius Energy Over a Stretching Surface","authors":"Utpal Jyoti Das,&nbsp;Indushri Patgiri","doi":"10.1002/htj.23264","DOIUrl":"https://doi.org/10.1002/htj.23264","url":null,"abstract":"<div>\u0000 \u0000 <p>The motivation of this study is to explore the magnetohydrodynamic flow of the Newtonian fluid model, focusing on the effects of thermophoresis and nonlinear convection on the viscous fluid in a stretchy sheet embedded in permeable media. This work aims to study the flow behavior, including the novel effects of radiative heat in the energy equation and energy activation in the concentration equation. Through proper similarity variables, governing equations are transformed to dimension-free form. The nonlinear dimension-free equations are solved via the bvp4c tool. The study of stagnation-point flow for a viscous nanofluid towards a stretchable area offers a comprehensive understanding of the relationships between fluid dynamics, heat transportation, and material properties. The flow behavior of several physical factors is studied graphically for temperature, velocity, and concentration boundary layer. Moreover, skin friction, mass, and heat transmission rates are important in this investigation. The impact of skin friction, heat, and mass transmission rates are represented in a table. From observation, it is highlighted that the permeability parameter reduces fluid velocity and the heat transport rate. Magnetic parameter enhances skin friction. Heat and mass transfer rates decrease by 0.39% and 0.21%, respectively, whereas skin friction rises by 6.19% when <i>M</i> is increased by 0.5 from 0.5 to 1. The heat transfer rate increases by 0.06% when the activation energy is increased by 0.2 from 0.4 to 0.6, but the mass transfer rate declines by 39.8%. Eckert number and radiation parameters enhance the fluid's temperature. The concentration boundary layer reduces for increasing chemical reactions and Schmidt numbers. This research helps design efficient systems and processes for engineering and commercial uses incorporating fluid motion and heat exchange.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 3","pages":"1841-1850"},"PeriodicalIF":2.8,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Simulations of Heat and Mass Transfer Enhancement Over a Rotating Cone","authors":"Saquib Ul Zaman,&nbsp;Sameed Ahmad","doi":"10.1002/htj.23251","DOIUrl":"https://doi.org/10.1002/htj.23251","url":null,"abstract":"<div>\u0000 \u0000 <p>In this work, we investigate the combined effects of heat and mass exchange on the time-dependent convectional flow of a rheological nanofluid across a rotating cone. A numerical arrangement of nonlinear differential equations is obtained for spinning cones with separator temperature boundary conditions by similarity transformation. The effect of different parameters on the velocity, temperature, and concentration profiles are discussed. Tangential velocity is observed to decrease with an increase in the Deborah number, whereas it increases with increasing values of the angular velocity ratio, relaxation to the retardation time ratio, and buoyancy parameter. Expansion in the Prandtl number is noted to decrease the boundary-layer temperature and thickness. Nusselt number and skin disunion observations are also considered. It is discovered that the Nusselt number expands by expanding the lightness parameter and Prandtl number, whereas it increases by decreasing the Deborah number. We also noticed that the Sherwood number falls incrementally in Deborah and Prandtl numbers, but it upsurges with an increase in the buoyancy parameter. The effect of parameters on temperature is graphically displayed, and the face shear stress tabulated values and heat shift rate are included in tables.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 3","pages":"1832-1840"},"PeriodicalIF":2.8,"publicationDate":"2024-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetohydrodynamic Flow of Immiscible Couple Stress and Newtonian Fluids in a Porous Pipe With Navier Slip Effect","authors":"Yitagesu Daba,&nbsp;Gosa Gadisa","doi":"10.1002/htj.23255","DOIUrl":"https://doi.org/10.1002/htj.23255","url":null,"abstract":"<p>This work deals with the magnetohydrodnamic (MHD) flow of non-miscible couple stress and Newtonian fluids within a horizontally-oriented porous cylinder. The overall flow domain is divided into two separate regions. In the core area, identified as region I, the flow of the couple stress fluid takes place, while in region II, which forms the outer part of the flow area, the flow of Newtonian fluid occurs. The linear Navier slip condition on the cylinder's surface and continuity conditions for velocities and shear stresses, along with vanishing couple stress at the fluid-fluid surface, have been taken as boundary and interface conditions, respectively. The nonlinear partial differential equations describing the flow situation along with the boundary conditions are first mathematically formulated and, then cast in a dimensionless form. Closed-form solutions for velocities, wall shear stress, and total flow rate have been obtained by solving the non-dimensionalized governing equations through the direct method. The influences of different flow parameters on the velocity in both flow areas are depicted graphically. The numerical values of the total flow rate and the wall stress for various flow parameters are also tabulated. The examination of the obtained results indicates that the fluid velocities diminish with increases in the Hartmann number, viscosity ratio, and porosity parameter. Conversely, they escalate with higher Reynolds numbers, pressure gradients, and slip parameters. Furthermore, the increase in the couple stress parameter increases the velocity of the couple stress fluid (core region), while the velocity of the Newtonian fluid (peripheral region) remains nearly constant. The findings of this research align very well with the results documented in the existing literature. This study is novel as it examines, for the first time, the effects of slip and magnetic fields on the flow of two immiscible fluids (couple stress and Newtonian) through a porous medium in cylindrical coordinates.</p>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 3","pages":"1819-1831"},"PeriodicalIF":2.8,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/htj.23255","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Analytical and Numerical Methods to Solve Boundary-Layer Natural Convection Problem for Various Prandtl Number Fluids","authors":"Durgesh Kushawaha,&nbsp;Sushil Yadav,&nbsp;Rajiv Aggarwal","doi":"10.1002/htj.23260","DOIUrl":"https://doi.org/10.1002/htj.23260","url":null,"abstract":"<div>\u0000 \u0000 <p>Semianalytical approaches such as the Homotopy Perturbation Method (HPM) and Variational Iteration Method (VIM), as well as the Numerical Method, are investigated in this study to solve the boundary-layer natural convection problem for various Prandlt number fluids on a horizontal flat plate. Nonlinear partial differential expressions can be incorporated into the ordinary differential framework by applying appropriate transformations. The purpose of this study is to show how analytical solutions to heat transfer problems are more versatile and broadly applicable. The results of the analytical solutions are compared with numerical solutions, revealing a high level of approximation accuracy. The numerical findings clearly imply that the analytical techniques can produce accurate numerical solutions for nonlinear differential equations. We analyze the temperature distribution, velocity, and flow field under various conditions. The study found that temperature patterns, velocity distribution, and flow dynamics are all improved by raising the Prandtl numbers. As a result, the thickness of the boundary layer is significantly reduced, leading to an enhanced heat transfer rate at the moving surface. This reduction in boundary-layer thickness contributes to a more efficient convection process. The study further highlights that the HPM and the VIM both offer highly accurate approximations for solving nonlinear differential equations related to boundary-layer flow and heat transfer. Among these methods, HPM was found to provide a higher level of precision compared with VIM.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 3","pages":"1807-1818"},"PeriodicalIF":2.8,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetic Effect on Thermocapillary Flow of Silicon Melt in an Annulus","authors":"Ali Bendjaghlouli,&nbsp;Brahim Mahfoud,&nbsp;Hibet Errahmane Mahfoud","doi":"10.1002/htj.23262","DOIUrl":"https://doi.org/10.1002/htj.23262","url":null,"abstract":"<div>\u0000 \u0000 <p>Thermocapillary convection plays a crucial role in various processes, including the formation of crystals from a molten state. Recent studies have established that the oscillatory flow of the molten material during crystal growth is a significant contributor to the formation of undesirable micro-inhomogeneities. The oscillatory flow can cause uneven distribution of solute and impurities, leading to localized variations in crystal composition and structure. This article discusses the possibility of controlling bidirectional thermocapillary flow, which is one of the sources of inhomogeneity in produced crystals, using an external magnetic field. The model examined in this study is a shallow annulus filled with silicon melt. This research investigates the effects of the annular space and the magnetic field on the thermocapillary process. The mathematical model, formulated as partial differential equations, was solved using the finite-volume method. The results show the formation of hydrothermal waves with different azimuthal modes (<i>m</i> = 6, 4, and 3) corresponding, respectively, to the annular space <i>R</i> = 0.8, 0.7, and 0.6. Stronger magnetic fields attenuate the instabilities and reduce the vertical temperature gradient, transforming the isotherms into concentric circles, thereby improving the homogeneity of the crystals.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 3","pages":"1796-1806"},"PeriodicalIF":2.8,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143801818","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}