Heat Transfer最新文献

{"title":"Thermo-Enviro-Economic Study of Solar Concentrated Hexagonal Covered Tubular Still Using Interrupted and Tilted Receiver","authors":"Karima E. Amori,&nbsp;Tabark A. Hussien","doi":"10.1002/htj.23231","DOIUrl":"https://doi.org/10.1002/htj.23231","url":null,"abstract":"<div>\u0000 \u0000 <p>Solar energy is still commonly used to produce clean drinking water due to its simple construction, low maintenance, and ecofriendliness. This work aims to experimentally investigate the yield upgrade and the thermal performance of a novel concentrated single-axis tracking trough tubular solar still (TSS). This tubular still is identified by three baffles that generate four interrupted sections in the U-receiver, which is inserted with copper mesh and fitted in a hexagonal-shaped glass cover. Two identical TSS models were side-by-side outdoor tested in Baghdad-Iraq 33.3° N and 43.3° E from January to March 2024. The first is inserted with black copper mesh (Model I), and the other has no insertion (Model ll). The effect of the inserted copper mesh (60, 120, and 180 g) and the receivers' tilt angle (5°, 10°, and 15°) on the still performance are involved. The still thermal performance is analyzed per heat transfer coefficients, energy, and exergy efficiencies. The results revealed that the accumulated daily yield is enhanced for Model I by 78.9%–194.8% while the thermal efficiency is enhanced by 68.3%–206.4% when it is tilted at 15° with the insertion of 60–180 g copper mesh, respectively, compared with Model II. It is concluded that an effective improvement in the solar still yield is obtained by using copper mesh.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1488-1505"},"PeriodicalIF":2.8,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143381080","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 Investigation of Pool Boiling Heat Transfer on Cu─Al2O3 Composite Coated Patterned Surfaces Using Refrigerant R-134a","authors":"Ajay D. Pingale,&nbsp;Govind Waghmare,&nbsp;Anil S. Katarkar,&nbsp;Sagar Wankhede,&nbsp;Swapan Bhaumik,&nbsp;Sachin Belgamwar","doi":"10.1002/htj.23235","DOIUrl":"https://doi.org/10.1002/htj.23235","url":null,"abstract":"<div>\u0000 \u0000 <p>The present study investigates pool boiling heat transfer (PBHT) of R-134a on Cu─Al₂O₃ composite-coated patterned surfaces (CPS_I, CPS_II, CPS_III, and CPS_IV). Using a wire EDM method, four different types of copper patterned surfaces (PS_I, PS_II, PS_III, and PS_IV) were manufactured. Comparing the heat transfer coefficients (HTCs) of the Cu─Al₂O₃ composite-coated patterned surfaces to the uncoated Cu surfaces, a notable enhancement was observed. The maximum HTC improvements of 162%, 178%, 189%, and 211% were observed for CPS_I, CPS_II, CPS_III, and CPS_IV, respectively, when compared with bare Cu surfaces. These results demonstrate the effectiveness of these treatments in enhancing heat transfer compared to bare copper surfaces. The enhancement in PBHT is mainly due to the integration of porous Cu─Al₂O₃ composite coating with patterned surfaces which resulted in a larger heat transfer area, improved capillary action, and a substantial increase in active nucleation sites.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1476-1487"},"PeriodicalIF":2.8,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380924","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":"Thermo-Solutal Nonlinear Convection in a Nanofluid Flow Past a Porous Plate in the Presence of Heat Generation/Absorption","authors":"Sudip Dey,&nbsp;Swati Mukhopadhyay,&nbsp;Kuppalapalle Vajravelu","doi":"10.1002/htj.23221","DOIUrl":"https://doi.org/10.1002/htj.23221","url":null,"abstract":"<div>\u0000 \u0000 <p>The aim of the present study is to analyze the effects of thermo-solutal nonlinear convection in a nanofluid flow past a vertical permeable plate in the presence of heat generation/absorption and a first-order chemical reaction. The effects of Brownian motion and thermophoresis have been included in this study. By using similarity transformations, the ordinary differential equations (ODEs) are obtained from the governing partial differential equations (PDEs). Then by using a Runge-Kutta (R-K) method coupled with a shooting technique, numerical solutions are obtained. The effects of the relevant physical parameters on the velocity, the temperature, and the nanoparticle volume fraction are analyzed. When the magnitude of the thermal buoyancy parameter and solutal buoyancy parameter increase, the fluid velocity initially rises rapidly and then diminishes. But the temperature and concentration fields reduce. Near the plate, the fluid velocity is found to enhance with increasing values of the thermo-quadratic convection parameter as well as with the rising values of the solutal-quadratic convection parameter. However, both the temperature and the nanoparticle volume fraction reduce. The results of this study are interesting and motivating for further investigations on the problem for different situations and with different geometries.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1394-1419"},"PeriodicalIF":2.8,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380719","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":"Impacts of Double Rotating Cylinders on the Forced Convection of Nanoencapsulated Phase Change Material","authors":"Aissa Abderrahmane,&nbsp;Houssem Laidoudi,&nbsp;Alhadj Hisseine Issaka Ali,&nbsp;Abdeldjalil Belazreg,&nbsp;Obai Younis,&nbsp;Riadh Marzouki","doi":"10.1002/htj.23234","DOIUrl":"https://doi.org/10.1002/htj.23234","url":null,"abstract":"<div>\u0000 \u0000 <p>Many engineering and industrial applications rely on heat transfer (HT) as a basic and central process. Therefore, engineers and researchers place significant emphasis on optimizing HT rates. Here, we numerically attempt to maximize the heat transmission rate of mixed convection of nanoencapsulated phase change material in a square compartment. The compartment is differentially heated and incorporates two cold rotating cylinders. The Galerkin finite element approach is utilized for addressing the system governing equations. A range of various factors affecting the thermal activity in the compartment were considered. These factors include the speed of spinning cylinders (<i>Re</i> = 0–1000), the porousness of the compartment (<i>Da</i> = 10⁻⁵–10⁻²), the magnetic field intensity (<i>Ha</i> = 0–100), and the concentration of nanoadditives (<i>ϕ</i> = 0%–8%). The obtained numerical findings demonstrated that the thermal activity inside the compartment is positively correlated to the speed of the spinning cylinders, the concentration of nanoadditives, and the porousness of the compartment. In contrast, increasing the intensity of the magnetic field obstructs the heat transmission. It was noted that at the highest <i>Re</i> number, the average Nusselt number augmented by 257% and 13.6% when increasing <i>Da</i> and <i>ϕ</i>, respectively.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1448-1461"},"PeriodicalIF":2.8,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380718","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":"Effects of Thermal Performance Enhancement on PTC Downsizing With Emphasis on Cost Savings and Commercial Feasibility: An Extended Evaluation Criterion","authors":"Nabil Bessanane,&nbsp;Yassine Demagh,&nbsp;Mohamed Si-ameur,&nbsp;Mourad Rebay","doi":"10.1002/htj.23174","DOIUrl":"https://doi.org/10.1002/htj.23174","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 &lt;p&gt;This study proposes a new comparative analysis and introduces a new criterion for evaluating the size reduction of heat exchangers, particularly relevant in the context of parabolic trough receivers. Various innovative receivers from the literature, employing different enhancement techniques, were compared with the conventional straight receiver. On the basis of the principle of similarity and using a previously validated one-dimensional mathematical model and numerical code, a parametric analysis was used to estimate reduction ratios &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 \u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;(&lt;/mo&gt;\u0000 \u0000 &lt;mi&gt;ζ&lt;/mi&gt;\u0000 \u0000 &lt;mo&gt;)&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; &lt;math altimg=\"urn:x-wiley:26884534:media:htj23174:htj23174-math-0001\" wiley:location=\"equation/htj23174-math-0001.png\" display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;unicode{x003B6}&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; and sizes for different solar receivers. For well-defined receiver geometries, the main results reveal consistent reduction ratios of around 99.7% and 93.53% for helical screw-tape and wavy receivers, respectively. This translates to size reductions of approximately 0.3 and 6.5 m compared with a 100-m-long conventional straight receiver, respectively. By integrating the &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 \u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;ζ&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; &lt;math altimg=\"urn:x-wiley:26884534:media:htj23174:htj23174-math-0002\" wiley:location=\"equation/htj23174-math-0002.png\" display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi&gt;unicode{x003B6}&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; ratio and the performance evaluation criterion (PEC) into a unified metric mPEC = PEC/&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 \u0000 &lt;mrow&gt;\u0000 &lt;msup&gt;\u0000 &lt;mi&gt;ζ&lt;/mi&gt;\u0000 \u0000 &lt;mn&gt;3&lt;/mn&gt;\u0000 &lt;/msup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; &lt;math altimg=\"urn:x-wiley:26884534:media:htj23174:htj23174-math-0003\" wiley:location=\"equation/htj23174-math-0003.png\" display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;msup&gt;&lt;mi&gt;unicode{x003B6}&lt;/mi&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, which","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1331-1349"},"PeriodicalIF":2.8,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380973","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":"MHD Mass Transfer Flow in Presence of Chemical Reaction, Thermal Radiation, and Thermal Diffusion Effect","authors":"Nazibuddin Ahmed,&nbsp;Hiren Deka,&nbsp;Puja Haloi","doi":"10.1002/htj.23219","DOIUrl":"https://doi.org/10.1002/htj.23219","url":null,"abstract":"<div>\u0000 \u0000 <p>The present work is interested in investigating the impacts of chemical reaction, magnetic field, thermal radiation, heat sink, and thermal diffusion on a steady two-dimensional MHD convection-free heat and mass transfer flow past a semi-infinite upright porous plate. The dimensionless domain equations are solved analytically using the perturbation technique for two distinct scenarios: (a) small suction and (b) large suction. The effects of various crucial parameters on velocity, temperature, concentration, as well as on the skin friction, Nusselt number, and Sherwood number are graphically illustrated, and the subsequent discussion is rooted on the derived outcomes. Graphical representations were created utilizing MATLAB software. The results suggest that an increase in the Soret effect elevates both the momentum and concentration boundary layers while reducing the mass transfer rate, regardless of the suction intensity. Our research also identified a captivating result where fluid velocity escalates with higher magnetic values in the scenario of large suction, while it demonstrates contrasting behavior under small suction condition. The present investigation holds significant relevance across various industrial sectors, including uranium enrichment, petrology, petroleum reservoirs, polymer fractionation, among others.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1358-1375"},"PeriodicalIF":2.8,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380710","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 Analysis of the Thermal Performance of a Hybrid Heat Sink Comprised of Perforated Foam Fins Embedded Within a Phase Change Material","authors":"Ali Hussein F. Theeb,&nbsp;Ihsan Y. Hussain","doi":"10.1002/htj.23220","DOIUrl":"https://doi.org/10.1002/htj.23220","url":null,"abstract":"<div>\u0000 \u0000 <p>This study presented a numerical model to evaluate a novel design of a hybrid heat sink incorporating perforated foam fins (PFFs) instead of solid fins (SFs) within a phase change material (PCM). This innovation is designed to enhance thermal performance in electronic cooling applications. The base of the heat sink was subjected to constant heat fluxes of 2, 3, and 4 kW/m². The effect of the perforation location (top, center, and bottom) within the foam fin and foam porosities (0.85, 0.90, and 0.95) were investigated. The results showed that the hybrid PFF design demonstrably improved thermal efficiency compared to the SF configuration. This innovative approach offered three benefits: a significant reduction in overall heat sink weight, an augmentation of the thermal conductivity of PCM, and the intermixed molten PCM between the fins passages through perforations. The PFF heat sink extended the operational time by 6%–8% for the range of heat fluxes at SPT of 70°C and led to a 24.5% increase in PCM volume, compared to the SF configuration. Complete melting of the PCM in the PFF heat sink is observed at 29 min for the highest heat flux of 4 kW/m², while the melting rates are 25% and 62% for the applied heat flux of 2 and 3 kW/m². Perforation location within the foam fin (top, center, and bottom) achieved equivalent heat transfer capabilities, enabling design flexibility for perforation location. The PFF with a porosity of 0.85 demonstrated superior thermal performance.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1376-1393"},"PeriodicalIF":2.8,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380711","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 Computational Analysis of Air-Cooled Heat Sinks Designs for PV Solar Panel Cooling With Different Fin Numbers","authors":"Abdullah Al Hasan,&nbsp;Md. Abdullah,&nbsp;Abu Soyeb Sazid","doi":"10.1002/htj.23236","DOIUrl":"https://doi.org/10.1002/htj.23236","url":null,"abstract":"<div>\u0000 \u0000 <p>The efficiency of photovoltaic (PV) solar panels is highly sensitive to operating temperatures, with increased temperatures leading to a significant decline in electrical output and overall performance. Despite extensive research into thermal management solutions for PV panels, there remains a gap in optimizing passive cooling systems, particularly air-cooled heat sinks, to achieve effective heat dissipation. This study addresses the challenge by conducting a detailed computational analysis of air-cooled heat sinks with varying fin configurations to enhance the thermal regulation of PV panels. Using computational fluid dynamics simulations, this work evaluates the influence of fin number and spacing on airflow dynamics and heat dissipation efficiency. Key findings from ANSYS Postprocessor simulations indicate that heat sinks with a higher number of fins improve heat dissipation, with the 11-fin configuration demonstrating the highest temperature drop of 38.44 K. Comparatively, the base model (nine fins, 0.05 m fin spacing) exhibited a maximum temperature of 331.46 K and a mean velocity of 1.58 m/s. A parametric study of finless designs showed a lower mean temperature of 321.28 K, but with significantly reduced airflow velocity. Intermediate designs, such as the six-fin and seven-fin heat sinks, also demonstrated improved thermal performance over the finless model but were outperformed by the 11-fin configuration. This study contributes to the ongoing efforts to optimize passive cooling for PV solar panels by demonstrating the critical impact of fin number on heat sink effectiveness. The findings offer valuable insights into the design of more efficient cooling mechanisms, potentially enhancing both the performance and longevity of PV systems.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1462-1475"},"PeriodicalIF":2.8,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380974","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":"Simulation of Magnetic Field Effects on Heat and Mass Transfer in a Porous Spline Half-Cylinder Using ANN and ISPH Approaches","authors":"Munirah Aali Alotaibi,&nbsp;Weaam Alhejaili,&nbsp;Samiyah Almalki,&nbsp;Abdelraheem M. Aly","doi":"10.1002/htj.23224","DOIUrl":"https://doi.org/10.1002/htj.23224","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 &lt;p&gt;This study utilizes Artificial Neural Networks (ANNs) and Incompressible Smoothed Particle Hydrodynamics (ISPH) simulations to explore the effects of magnetic fields on heat and mass transfer in a porous spline half-cylinder filled with Nano-Encapsulated Phase Change Material (NEPCM). Simulations were conducted over a range of physical parameters: buoyancy ratio (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 \u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;N&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; &lt;math altimg=\"urn:x-wiley:26884534:media:htj23224:htj23224-math-0001\" wiley:location=\"equation/htj23224-math-0001.png\" display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi&gt;N&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) from −2 to 2, Darcy number (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 \u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;Da&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; &lt;math altimg=\"urn:x-wiley:26884534:media:htj23224:htj23224-math-0002\" wiley:location=\"equation/htj23224-math-0002.png\" display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant=\"italic\"&gt;Da&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) from 10&lt;sup&gt;−5&lt;/sup&gt; to 10&lt;sup&gt;−2&lt;/sup&gt;, Hartmann number (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 \u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;Ha&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; &lt;math altimg=\"urn:x-wiley:26884534:media:htj23224:htj23224-math-0003\" wiley:location=\"equation/htj23224-math-0003.png\" display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi mathvariant=\"italic\"&gt;Ha&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) from 0 to 50, Rayleigh number (&lt;i&gt;Ra&lt;/i&gt;) from 10&lt;sup&gt;3&lt;/sup&gt; to 10&lt;sup&gt;6&lt;/sup&gt;, and fusion temperature &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 \u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;(&lt;/mo&gt;\u0000 \u0000 &lt;msub&gt;\u0000 &lt;mi&gt;θ&lt;/mi&gt;\u0000 \u0000 &lt;mi&gt;f&lt;/mi&gt;\u0000 &lt;/msub&gt;\u0000 \u0000 &lt;mo&gt;)&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; &lt;math altimg=\"urn:x-wiley:26884534:media:htj23224:htj23224-math-0004\" wiley:location=\"equation/htj23224-math-0004.png\" display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mo str","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1420-1433"},"PeriodicalIF":2.8,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380807","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 the Performance of Split Unit Air-Conditioning System by Integrating Air–PCM Heat Transfer Unit: Numerical and Experimental Assessment","authors":"Noor A. Hussein,&nbsp;Amar S. Abdul-Zahra,&nbsp;Ayad M. Al Jubori","doi":"10.1002/htj.23232","DOIUrl":"https://doi.org/10.1002/htj.23232","url":null,"abstract":"<div>\u0000 \u0000 <p>The growing need for energy-efficient cooling solutions has driven the exploration of cutting-edge technologies in air-conditioning (AC) systems. Therefore, this research aims to improve the energy efficiency of a split AC system by incorporating a phase change material (PCM) heat transfer element into the AC system. PCM can release and store thermal energy, assisting in decreasing the load on the AC system during peak cooling periods. The PCM utilized in the study is Rubitherm RT18HC. The study includes numerical and experimental evaluations to assess the impact of the air–PCM unit on the split unit's performance. The numerical simulations were conducted using computational fluid dynamics models based on ANSYS-Fluent to choose the best design and conditions for the air–PCM unit. The experimental study was conducted in the hot environment of Iraq, where outdoor temperatures exceed 43°C. The numerical results showed that the best design and conditions concluded to be a 1-cm PCM height in the panels, 3 cm air channel height, 0.9 m/s air velocity for charging, 0.45 m/s air velocity for discharging, 7°C inlet air temperature for charging, and 25°C inlet air temperature for discharging. In the experimental part, after validating the theoretical results, two practical cases were conducted to evaluate the split unit performance with and without PCM. The results showed an average of 5% lower room temperature, 9.5% lower air entering the evaporator temperature, 10% lower energy consumption, and a 12.5% increase in the AC unit's coefficient of performance when using the air–PCM heat transfer unit.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1434-1447"},"PeriodicalIF":2.8,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380717","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}