Heat Transfer最新文献

{"title":"Geometric Optimization of Multitube Heat Exchangers for Enhanced Thermal Performance in PCM-based Energy Storage Systems","authors":"Hussein A. Abdullhussein,&nbsp;Munther Abdullah Mussa","doi":"10.1002/htj.23368","DOIUrl":"https://doi.org/10.1002/htj.23368","url":null,"abstract":"<div>\u0000 \u0000 <p>This study investigates the thermal performance enhancement of phase change material (PCM)-based thermal energy storage systems via the geometric optimization of multitube heat exchangers. A numerical analysis performed using ANSYS Fluent evaluates configurations with 1, 2, 3, and 4 inner copper tubes while keeping the PCM mass and the heat-transfer fluid flow rate constant. Our results demonstrate that increasing the number of tubes significantly improves the charging efficiency of the PCM. In particular, the four-tube design achieves complete melting in 105 min, a 77% reduction compared with the single-tube benchmark (448 min). This improvement is attributed to an expanded heat-transfer surface area (an increase from 0.0703 to 0.1408 m²) and enhanced natural convection due to distributed heat sources and higher aspect ratios (28.57–57.14). The multitube configuration outperforms other augmentation strategies, such as nanoparticle additives and finned systems, by maintaining structural simplicity without adding material complexity. Notably, the design utilizes cost-effective Iraqi paraffin, underscoring its potential for localized applications. Although our simulations assume laminar flow and adiabatic boundaries, our findings highlight the viability of geometric optimization to overcome the intrinsic low thermal conductivity of PCMs. This study fills a critical research gap by quantifying the influence of tube multiplicity on PCM dynamics, offering a scalable solution for renewable energy storage. Future studies should validate these numerical results experimentally and investigate the effects of turbulent flow and economic feasibility.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 5","pages":"3494-3506"},"PeriodicalIF":2.8,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144256518","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":"Exergy Analysis of Heat Pump Polygeneration System","authors":"Vajeer Baba Shaik,&nbsp;Srinivas Tangellapalli,&nbsp;Rajeev Kukreja","doi":"10.1002/htj.23367","DOIUrl":"https://doi.org/10.1002/htj.23367","url":null,"abstract":"<div>\u0000 \u0000 <p>Environmental degradation and sustainable development are currently two of the most significant global challenges. Among these, producing drinking water, chill air, hot air, and expanding renewable energy methods are paramount. The effective use of advanced technology to produce multiple outputs has demonstrated itself to be a reliable, affordable, and competitive approach to energy generation. Polygeneration technologies' high productivity stems from their ability to recover energy that would otherwise be wasted. So, this study aims to combine the solar-powered heat pump/VCR with a humidification, dehumidification, and desalination cycle for polygeneration. In order to minimize the thermal pollution from this system, waste heat from the VCR's condenser has been recovered and utilized to produce hot water and fresh water along with a cooling effect. The investigation evaluates the effect of seawater temperature, humidifier efficiency, relative humidity, and the surrounding temperature on the performance factors, that is, thermodynamic and exergy analysis. A mathematical model has been simulated using MATLAB, yielding key performance metrics: a gained output ratio of 1.909, a coefficient of performance of 1.724, a thermal performance factor of 3.786 for the cycle and 0.565 for the plant, and an exergy efficiency of 27.52%. These results highlight the potentiality of the heat pump polygeneration system in providing sustainable and efficient solution for domestic needs.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 5","pages":"3473-3493"},"PeriodicalIF":2.8,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144255859","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 Tissue-Stratified Anatomic Three-Dimensional Heat Transfer Model for Evaluating Human Body Thermoregulatory Responses to Extreme Metabolic and Environmental Stressors","authors":"Amjed A. A.,&nbsp;Luma F. Ali","doi":"10.1002/htj.23366","DOIUrl":"https://doi.org/10.1002/htj.23366","url":null,"abstract":"<div>\u0000 \u0000 <p>In this study, an improved three-dimensional (3D) human thermoregulation model was developed. A stratified model of the segmented human geometry was introduced, characterizing distinct tissues and organs to activate their specific thermal responses and interactions. The main trunk geometry was modified to improve reliability and support applications, such as personal cooling systems. The model accounted for heat transport via blood arteries and emphasized changes in skin thermal conductivity to simulate vasodilation and vasoconstriction mechanisms. Additionally, the thermal effects of direct solar radiation on the human body were integrated into the mathematical framework. The model was validated using documented experimental data across various hot and cold environmental conditions and compared with recent 3D models. Results demonstrated that the enhanced model achieved better agreement with experimental data than existing unstratified segmented models. Improved stratification captured temperature variations across adjacent tissue layers, providing more accurate peripheral and core temperature distributions. A case study investigated strenuous military tasks performed under extreme heat, yielding significant medical insights. This advanced stratified anatomic model serves as a robust tool for predicting human thermoregulation during diverse activities, offering detailed core and skin temperature distributions. Furthermore, the modified sweepable geometry may enhance numerical methodologies for future 3D studies.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 5","pages":"3451-3472"},"PeriodicalIF":2.8,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144256517","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":"Forced Convection Analysis of an Oscillating Blade in a Straight Channel: Effects of Blade's Initial Position","authors":"Abdullah Al Mehedi,&nbsp;Durjoy Kumar Paul,&nbsp;Nishitha Paul","doi":"10.1002/htj.23316","DOIUrl":"https://doi.org/10.1002/htj.23316","url":null,"abstract":"<div>\u0000 \u0000 <p>The present computational study examines the transient analysis of forced convective flow and heat transfer in a long open channel with an oscillating blade initially placed either horizontally or vertically to investigate the impacts on the heat transfer performance and pressure drop in the channel of the blade's position. For mathematical modeling, the Arbitrary Lagrangian–Eulerian finite element method has been employed to precisely model the moving mesh boundary conditions under various simulation parameters. Simulations are performed for the Reynolds number, <i>Re</i> = 50, and Prandtl number, <i>Pr</i> = 1. The nondimensional maximum linear velocity and oscillating frequency are modified with the values <i>V</i>_m = 0.5, 1.0, 2.0, and <i>F</i>_c = 0.2, 0.5, 0.8. The results show that the vertically positioned blade provides the best thermal performance at <i>V</i>_m = 1.0 and <i>F</i>_c = 0.8, together with the maximum average cavity pressure drop, while the horizontally positioned blade becomes the least thermoefficient at <i>V</i>_m = 0.5 and <i>F</i>_c = 0.8, with the corresponding lowest average pressure drop. It can also be observed that the initial blade position significantly impacts both heat transfer and pressure drop characteristics. A vertically positioned blade demonstrates superior heat transfer performance compared with a horizontally positioned blade. The analysis may be crucial for determining the impact of an oscillating body on the heat transfer and pressure drop encountered in different high heat flux applications, like, crystal formation, high-performance building insulation, solar distiller, solar energy collectors, nuclear reactors, electronic device cooling, drying technology, and so forth.</p></div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 5","pages":"3432-3450"},"PeriodicalIF":2.8,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144256567","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":"Boundary Layer Convective Flow in a Divergent Channel With Melting Heat Transfer and Mass Suction/Injection: An Analysis Using ANN and Numerical Methods","authors":"S. Ramprasad,&nbsp;B. Mallikarjuna,&nbsp;Nagabhushana Pulla","doi":"10.1002/htj.23363","DOIUrl":"https://doi.org/10.1002/htj.23363","url":null,"abstract":"<div>\u0000 \u0000 <p>This study investigates magnetohydrodynamic fluids in converging and diverging channels, with a focus on melting heat transfer effects. The investigation utilizes a combination of numerical techniques, specifically the finite element Galerkin method, and artificial neural network (ANN) modeling to examine fluid flow behavior and thermal patterns in various channel configurations. Numerical explanations are provided for the effect of these factors on temperature, velocity, local skin friction, and Nusselt number distributions. Upon careful analysis and graphical presentation, the acquired data provide a significant understanding of how different physical parameters affect the flow properties. The contrast between the current and past findings reveals a good agreement. The findings have important applications in engineering fields where specific control of fluid flow and heat transfer is essential, including plastic sheet extrusion, electronic device cooling, and metal casting. Additionally, the research employs ANN to enhance the prediction of heat transfer characteristics, demonstrating a strong correlation between predicted and theoretical results. Accurate regulation of fluid flow and heat transmission is crucial in technical areas, such as metal casting, plastic sheet extrusion, and electronic device cooling.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 5","pages":"3405-3417"},"PeriodicalIF":2.8,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144256559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Correlation of the Steel's Thermophysical Properties for Thermal Engineering Applications","authors":"Yanan Camaraza-Medina","doi":"10.1002/htj.23369","DOIUrl":"https://doi.org/10.1002/htj.23369","url":null,"abstract":"<div>\u0000 \u0000 <p>In this study, a predictive method is presented to estimate the variation of three thermophysical properties (thermal diffusivity, specific heat, and thermal conductivity) of 32 AISI-SAE commercial classes of rolled and annealed steels, at a working temperature from 0°C to 800°C and with a composition (C, Mn, S, P, Ni, Si, Mo, Cr, V). The function adjustment method is used for the treatment and generalization of the available experimental data, obtaining an equation that provides satisfactory adjustments to extend its use to thermal engineering. The proposed models were verified by comparison with available experimental data. For thermal diffusivity, specific heat, and thermal conductivity, the models obtained correlate with a deviation of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mo>±</mo>\u0000 \u0000 <mn>17.6</mn>\u0000 \u0000 <mo>%</mo>\u0000 </mrow>\u0000 </mrow>\u0000 </semantics></math>, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mo>±</mo>\u0000 \u0000 <mn>8.2</mn>\u0000 \u0000 <mo>%</mo>\u0000 </mrow>\u0000 </mrow>\u0000 </semantics></math>, and <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mo>±</mo>\u0000 \u0000 <mn>16.6</mn>\u0000 \u0000 <mo>%</mo>\u0000 </mrow>\u0000 </mrow>\u0000 </semantics></math>, respectively. The weaker correlation fit corresponds to the thermal diffusivity of AISI-SAE 316 steel, with a maximum error of 17.6% and a mean absolute error (MAE) of 8.2% in 80.6% of the available experimental data. The best fit is provided by the specific heat of the AISI-SAE 1078 steel, with a maximum error of 1.9% and an MAE of 1.1% in 68.3% of the available experimental samples. In all cases, the agreement of the proposed model with the available experimental data is good enough to be considered satisfactory for practical design.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 5","pages":"3418-3431"},"PeriodicalIF":2.8,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144256558","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":"Cross-Diffusion Effects on Magnetohydrodynamic Free Convective Flow Over a Vertical Porous Plate Under the Influence of Chemical Reactions, Thermal Radiation, and Dissipative Heating","authors":"V. B. Rajakumar Komaravolu,&nbsp;Tangudu Govinda Rao,&nbsp;Kuppareddy Subramanyam Balamurugan,&nbsp;Chargarlamudi Baby Rani","doi":"10.1002/htj.23358","DOIUrl":"https://doi.org/10.1002/htj.23358","url":null,"abstract":"<div>\u0000 \u0000 <p>The main objective of the current study is to analyze the coupled influence of Dufour and Soret diffusion on magnetohydrodynamic free convective flow over an infinite vertical porous plate, focusing on the interdependence of heat and mass transfer. The novelty of this study lies in highlighting the complex relationship between thermal and solutal diffusion in the presence of chemical reactions, thermal radiation, viscous dissipation, Ohmic heating and an internal heat source factors that are often considered separately in previous studies. The governing equations for velocity, temperature and concentration are solved using the multiple regular perturbation method. The findings reveal that an increase in the Dufour number enhances mass diffusion driven by thermal gradients, reducing velocity and concentration while increasing temperature and skin friction. Conversely, a higher Soret number suppresses velocity, with temperature and concentration exhibiting opposite trends. Additionally, the Sherwood number decreases with rising Dufour, Soret, and Schmidt numbers, highlighting the strong coupling between heat and mass transfer in magnetohydrodynamic flows. These results provide new insights into transport phenomena in MHD systems, with potential applications in industrial and engineering processes.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 5","pages":"3374-3391"},"PeriodicalIF":2.8,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144256521","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":"Enhancing Thermal Performance of Solar Water Heater System Through Collector Area Optimization","authors":"Mohammed Hussien Alkhafaji,&nbsp;Mohammed H. Alhamdo,&nbsp;Basim Freegah,&nbsp;Qasim Saleh","doi":"10.1002/htj.23364","DOIUrl":"https://doi.org/10.1002/htj.23364","url":null,"abstract":"<div>\u0000 \u0000 <p>This study investigates the enhancement of thermal efficiency in a solar water heating system by increasing the surface area exposed to sunlight without modifying the collector's primary dimensions. Three design modifications were explored: (i) incorporating four rows of camber, (ii) adding four rows of pin fins, and (iii) integrating four vertical fins. Numerical simulations were conducted using ANSYS to evaluate the theoretical impact of these modifications, while an experimental assessment of a conventional solar collector was performed for validation. The experimental and numerical results showed strong agreement, confirming the reliability of the computational model. Compared to the conventional design, the modified collectors are found to achieve higher water temperatures in the storage tank by 2.1%, 2.4%, and 19.2% for models (four rows of camber, adding four rows of pin fins, and added four vertical fins), respectively. Additionally, the results indicated that the mass flow rates increased by about 3.1%, 4.4%, and 8.1%, while the overall collector efficiency improved by 5.6%, 6.1%, and 16.5%. These findings demonstrate the potential of surface area modifications to enhance the performance of solar water heating systems.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 5","pages":"3392-3404"},"PeriodicalIF":2.8,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144256522","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 Unsteady Oriented Magneto-Convective Porous Medium: Exploring Boundary-Layer Flow Dynamics Through Regression Modeling","authors":"Mohammed Jahir Uddin,&nbsp;Rehena Nasrin,&nbsp;Eid S. Alatawi","doi":"10.1002/htj.23347","DOIUrl":"https://doi.org/10.1002/htj.23347","url":null,"abstract":"<div>\u0000 \u0000 <p>Exploring flow stability in porous media, the consequence of magnetic fields on heat transfer (HT), the influence of inclination on flow, and optimizing industrial cooling systems are crucial. This study explores the stability of magneto-convective flow in unsteady porous media, focusing on orientation effects and the impact of boundary layer (BL) conditions on flow behavior and heat transmission while developing regression models to predict these dynamics. We explore nonlinear, time-varying partial differential equations (PDEs) that govern mass conservation, momentum, energy, and concentration, making relevant adjustments as required. A comprehensive numerical framework is developed to address these governing equations, employing a finite difference method (FDM) for spatial discretization and an implicit approach for time integration. Through stability analysis, we assess the flow behavior under diverse conditions, elucidating the critical parameters influencing flow stability and transitions. Furthermore, an extensive investigation is undertaken to establish a suitable steady-state condition and to ensure uniform meshing throughout the process. Regression analysis is applied to elucidate the relationships between the key factors. This study examines the consequence of several physical factors on the distribution of velocity, temperature, and concentration within the system. The findings indicate that increasing the mass Grashof number significantly enhances buoyancy-driven convection, while an inclined magnetic field profoundly modifies the flow dynamics and thermal profiles. The newly developed two linear regression models of multiple variables have 95.25% and 98.49% correlation coefficients for mean Nusselt number and shear stress, respectively. The study's originality lies in its detailed examination of how these parameters interact to impact inclined magnetic field convection flows. This comprehensive understanding may facilitate more accurate predictive models and enhancements in engineering design. It is significant for several industries, including petroleum and agricultural engineering, gas turbines, nuclear power facilities, heat exchangers, cooling systems, and chemical processing.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 5","pages":"3332-3365"},"PeriodicalIF":2.8,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144255964","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 New Heat Flux Model for MHD Shear Thickening Fluid Flow Past a Cylinder With Radiation and Variable Heat Source/Sink","authors":"Kempannagari Anantha Kumar,&nbsp;Buruju Ramoorthy Reddy,&nbsp;Ankalagiri Chinna Venkata Ramudu","doi":"10.1002/htj.23360","DOIUrl":"https://doi.org/10.1002/htj.23360","url":null,"abstract":"<div>\u0000 \u0000 <p>The prime aim of the current investigation is to examine the magnetohydrodynamic flow of shear-thickening liquid subjected to the stretching of an extended cylinder in the ubiquity of a porous medium. A new typical heat flux ideal is used, including the effects of thermal radiative heat, convection, irregular heat generation or absorption, and Joule heating. By employing the similarity transmutations, the governing equations are reduced to nonlinear ODEs and solved using the R.K.-based shooting technique. Results are analyzed with graphs to assess the impact of parameters on the flow. The reduction in fluid temperature due to the thermal relaxation parameter suggests its potential application in cooling technologies, such as advanced heat exchangers, microchannel cooling, and industrial cooling systems, where precise thermal management is crucial. The higher heat transport rate with increased thermal stratification and radiation parameters indicates potential benefits in solar energy applications, such as solar collectors and thermal storage systems, where maximizing heat transfer efficiency is essential for improved energy capture and utilization.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 5","pages":"3366-3373"},"PeriodicalIF":2.8,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144255966","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}