Heat Transfer最新文献_第9页

Implementation of a Realistic Multicell CFD Model to Investigate the Thermal Characteristics Within a Solar PV Module 研究太阳能光伏组件热特性的真实多电池CFD模型的实现

IF 2.8

Heat Transfer Pub Date : 2024-12-12 DOI: 10.1002/htj.23256

Shubham Kumar, P. M. V. Subbarao

{"title":"Implementation of a Realistic Multicell CFD Model to Investigate the Thermal Characteristics Within a Solar PV Module","authors":"Shubham Kumar, P. M. V. Subbarao","doi":"10.1002/htj.23256","DOIUrl":"https://doi.org/10.1002/htj.23256","url":null,"abstract":"<div>\u0000 \u0000 <p>The thermal characteristics within a solar photovoltaic (PV) module are vital in determining its real field power output and lifetime. The structural and thermal complexities within a PV module have often been ignored in the past CFD-based research works. However, those complexities can substantially impact the thermal diffusion occurring within the module. The present study proposes a realistic multilayered multicell model in which the PV cells are considered as multiple distinct domains with encapsulant-filled discontinuities. The model is validated with experimental results and then implemented to investigate the cell temperature, thermal profile, and temperature gradients within a free-standing PV module in various wind conditions. The low thermal conductance of discontinuities among PV cells is found to be the key factor in raising the cell temperature 2°C–3°C above the back temperature. The current mismatch loss due to temperature nonuniformity is estimated to be up to 0.28% for a 50 W module and should be higher in bigger-size modules. Very high-temperature gradients (order of 10<sup>3</sup>°C/m) are observed in the encapsulant and backsheet layers near the cell edges, which can lead to high thermal stress and consequent degradation. The back temperature, temperature pattern along the surface, and location of hotter zones remain largely unaffected by the discontinuities among PV cells.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1719-1732"},"PeriodicalIF":2.8,"publicationDate":"2024-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380578","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}

引用次数: 0

Numerical Analysis of the Heat and Mass Transfer in a Ventilated Cavity for Turbulent Convective Flow With Extreme Hot and Humid Climate Conditions 极端湿热气候条件下紊流对流腔内传热传质的数值分析

IF 2.8

Heat Transfer Pub Date : 2024-12-09 DOI: 10.1002/htj.23246

J. Serrano-Arellano, F. N. Demesa López, K. M. Aguilar-Castro, J. M. Belman-Flores

{"title":"Numerical Analysis of the Heat and Mass Transfer in a Ventilated Cavity for Turbulent Convective Flow With Extreme Hot and Humid Climate Conditions","authors":"J. Serrano-Arellano, F. N. Demesa López, K. M. Aguilar-Castro, J. M. Belman-Flores","doi":"10.1002/htj.23246","DOIUrl":"https://doi.org/10.1002/htj.23246","url":null,"abstract":"<div>\u0000 \u0000 <p>To analyze the temperature and relative humidity (<i>RH</i>) in a room located in the Lacandona jungle in Chiapas, Mexico, a numerical heat and mass transfer study was performed. The study was carried out in a ventilated cavity, by introducing air flow into user-occupied spaces. The study analyzed the combination of temperature and humidity percentage to create thermal comfort conditions. The finite volume method was used to solve the governing equations, while pressure–velocity coupling was done with the SIMPLEC algorithm. Turbulent airflow was considered, and modeled using the <i>k–ε</i> turbulence model, with Reynolds numbers (<i>Re</i>) in the range from 100 to 5000. Seven sets of weather conditions were considered for a warm April day with solar radiation values that ranged from 0 to 981 W/m², outdoor temperatures between 19.9°C and 35.3°C, as well as <i>RH</i> from 42% up to 100%. The study analyzed temperature, <i>RH</i>, distribution efficiencies, and heat fluxes. It was found that the average temperature closest to thermal comfort was 25.8°C. This corresponds to an <i>Re</i> = 5000, being the best hygrothermal conditions with an average <i>RH</i> of 50%. However, this level of <i>RH</i> is unattainable by many air conditioning systems.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1691-1710"},"PeriodicalIF":2.8,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143379973","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}

引用次数: 0

Effect of Tray Geometry on Multitray Stepped Solar Still Performance: An Experimental Study 托盘几何形状对多托盘阶梯式太阳蒸馏器性能影响的实验研究

IF 2.8

Heat Transfer Pub Date : 2024-12-09 DOI: 10.1002/htj.23253

Ahmed Rahmani, Zine Saadi, Ouahid Keblouti

{"title":"Effect of Tray Geometry on Multitray Stepped Solar Still Performance: An Experimental Study","authors":"Ahmed Rahmani, Zine Saadi, Ouahid Keblouti","doi":"10.1002/htj.23253","DOIUrl":"https://doi.org/10.1002/htj.23253","url":null,"abstract":"<div>\u0000 \u0000 <p>The multitray solar still (MTSS) is one of the most efficient and economical designs compared with other solar still systems. MTSS has lower heat loss and a large evaporation area, and its basin is more exposed to solar radiation. Nevertheless, optimizing the tray's geometry is essential to improve the still's thermal behavior and productivity. The primary goal of this study is to examine the effect of the tray's geometry on the MTSS performance under outdoor experiments. A comparative analysis was conducted between the triangular-trays solar still (TTSS), the rectangular-trays solar still (RTSS), and the single-slope conventional solar still (CSS) in winter and summer weather conditions. Results show that integrating a multitray evaporator improves the daily yield compared with the CSS and that the thermal performance of the modified solar still depends mainly on the weather conditions. The comparison shows that the triangular trays are more effective than the rectangular ones. The daily productivity of TTSS exceeds that of RTSS by 10% in winter and 24.24% in summer. Moreover, the daily thermal efficiencies of CSS, RTSS, and TTSS are maximum in summer conditions by about 28.1%, 41.2%, and 44.15%, respectively.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1711-1718"},"PeriodicalIF":2.8,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143379972","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}

引用次数: 0

Analysis of the Influence of the Soret Number on Axisymmetric Flow Through the Application of the Successive Linearization Technique 应用连续线性化技术分析索列数对轴对称流动的影响

IF 2.8

Heat Transfer Pub Date : 2024-12-06 DOI: 10.1002/htj.23249

P. Pramod Kumar, Bala Siddulu Malga, Lakshmi Appidi, Ch. Mangamma, M. Sridevi, P. S. Ravi

引用次数: 0

Machine Learning Modeling of Anchovy Waste Treatment Using Solar Drying 太阳能干燥鳀鱼废弃物处理的机器学习建模

IF 2.8

Heat Transfer Pub Date : 2024-12-03 DOI: 10.1002/htj.23242

Najjar Mohammed, Tagnamas Zakaria, Bahammou Younes, Bouyghf Hamid, Nahid Mohammed

{"title":"Machine Learning Modeling of Anchovy Waste Treatment Using Solar Drying","authors":"Najjar Mohammed, Tagnamas Zakaria, Bahammou Younes, Bouyghf Hamid, Nahid Mohammed","doi":"10.1002/htj.23242","DOIUrl":"https://doi.org/10.1002/htj.23242","url":null,"abstract":"<div>\u0000 \u0000 <p>This study aims to valorize coproducts from the anchovy processing chain by obtaining compounds of interest through the implementation of environmentally friendly and energy-efficient techniques. These methods, which also apply to other fresh anchovy waste coproducts, seek to minimize the environmental pollution associated with conventional systems. The investigation focused on the application of solar drying as a treatment of anchovy waste. The resulting data were employed to model the drying behavior of anchovy waste using five machine learning algorithms. A thermokinetic study was conducted under both natural and forced convection solar drying to establish the optimal conditions for drying and storing anchovy heads, which are a significant source of high-quality proteins for human and animal nutrition. Drying kinetics were examined at three temperatures (60°C, 70°C, and 90°C) and two airflow rates (150 and 300 m<sup>3</sup>/h). The study identified air drying temperature as the most critical factor affecting the drying kinetics of anchovy wastes. Machine learning modeling of anchovy waste solar drying was conducted, and evaluated models were RNN, LSTM, GRU, LightGBM, and CatBoost. CatBoost demonstrated superior performance in predicting moisture content. It achieved the lowest Mean Squared Error of 1.1491e − 06, the lowest Mean Absolute Error of 0.0006265, and the highest coefficient of determination (<i>R</i><sup>2</sup>) of 99.99%. The comparative analysis highlighted distinct differences in the predictive accuracy of the models, with CatBoost emerging as the most effective.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1650-1664"},"PeriodicalIF":2.8,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380388","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}

引用次数: 0

Impact of Dual Phase Lag on Natural Convection Flow in a Porous Vertical Channel in the Presence of Periodic Boundary 存在周期边界时双相滞后对垂直孔道自然对流流动的影响

IF 2.8

Heat Transfer Pub Date : 2024-12-03 DOI: 10.1002/htj.23239

N. L. Mukhtar, H. M. Jibril

{"title":"Impact of Dual Phase Lag on Natural Convection Flow in a Porous Vertical Channel in the Presence of Periodic Boundary","authors":"N. L. Mukhtar, H. M. Jibril","doi":"10.1002/htj.23239","DOIUrl":"https://doi.org/10.1002/htj.23239","url":null,"abstract":"<div>\u0000 \u0000 <p>The dual-phase-lag (DPL) heat conduction model is utilized in this research to analyze the fluid flow of viscous fluid passing through a porous vertical channel with periodic boundary conditions. Periodic heating is subjected to the channel boundary. Equations regarding the model, including the momentum and energy equations, in which the DPL term is incorporated, all in dimensional form, are stated and are being transformed to their dimensionless form, then solved analytically by undetermined coefficients and variation of parameters. The actual expressions of temperature and velocity, as well as the heat transfer rate and skin friction, are determined. The effects of the DPL parameters, suction/injection, Prandtl number, heat source/sink, and Strouhal number on the dimensionless temperature and velocity profiles are demonstrated using graphs that are constructed with the aid of MATLAB. It was found during the investigation that the introduction of the DPL model, together with suction/injection in the channel, enhances the velocity and fluid temperature within the channel. Also, the decreasing effect of temperature gradient phase lag on fluid temperature and velocity conversed with that of heat flux phase lag. As an important contribution, the discovery of the effects of the phase-lag parameters of the DPL model and suction/injection on fluid temperature and velocity would significantly help researchers advance the design of electrical and electronic systems.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1623-1637"},"PeriodicalIF":2.8,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380462","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}

引用次数: 0

Validation of Magnesium Oxide Additive Effects on Diesel Engine Performance Through Crystal Structure and Thermal Stability Analyses 通过晶体结构和热稳定性分析验证氧化镁添加剂对柴油机性能的影响

IF 2.8

Heat Transfer Pub Date : 2024-12-03 DOI: 10.1002/htj.23250

Erdal Çılğın

引用次数: 0

Combined Impacts of Thermal and Mass Stratification on Unsteady MHD Parabolic Flow Along an Infinite Vertical Plate With Periodic Temperature Variation and Variable Mass Diffusion 热分层和质量分层对具有周期性温度变化和变质量扩散的无限垂直板非定常MHD抛物流的联合影响

IF 2.8

Heat Transfer Pub Date : 2024-12-03 DOI: 10.1002/htj.23240

Digbash Sahu, Rudra Kanta Deka

{"title":"Combined Impacts of Thermal and Mass Stratification on Unsteady MHD Parabolic Flow Along an Infinite Vertical Plate With Periodic Temperature Variation and Variable Mass Diffusion","authors":"Digbash Sahu, Rudra Kanta Deka","doi":"10.1002/htj.23240","DOIUrl":"https://doi.org/10.1002/htj.23240","url":null,"abstract":"<div>\u0000 \u0000 <p>This study investigates the dynamics of unsteady MHD parabolic flow along an infinite vertical plate, with a focus on the impacts of thermal and mass stratification under periodic temperature variations and variable mass diffusion. Utilizing the Laplace transform technique for deriving exact solutions, this research innovatively integrates both thermal and mass stratification effects without resorting to approximations. The main objective is to assess how these stratifications influence flow dynamics, temperature, and concentration profiles in environments with varying magnetic fields. The study contrasts these findings against classical non-stratification cases, offering a detailed comparison of fluid behavior under different conditions. Results indicate that thermal and mass stratifications substantially decrease velocity and stabilize temperature profiles, pointing to a damping effect on fluid motion while also controlling diffusion processes. These stratifications lead to higher Nusselt and Sherwood numbers, suggesting improved heat and mass transfer efficiencies. In contrast, the absence of stratification results in higher velocities and less stable temperature and concentration distributions. The findings underscore the significant role of stratification in optimizing fluid dynamics and enhancing the efficiency of heat and mass transfer processes, providing crucial insights for engineering and environmental applications where such conditions prevail.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1638-1649"},"PeriodicalIF":2.8,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380463","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}

引用次数: 0

Effect of Magnetic Field and Slip Conditions on Flow in a Rotating Porous Channel With Viscous Dissipation 磁场和滑移条件对具有粘性耗散的旋转多孔通道内流动的影响

IF 2.8

Heat Transfer Pub Date : 2024-12-02 DOI: 10.1002/htj.23241

Vineet Kumar Verma, Abdul Faiz Ansari

{"title":"Effect of Magnetic Field and Slip Conditions on Flow in a Rotating Porous Channel With Viscous Dissipation","authors":"Vineet Kumar Verma, Abdul Faiz Ansari","doi":"10.1002/htj.23241","DOIUrl":"https://doi.org/10.1002/htj.23241","url":null,"abstract":"<div>\u0000 \u0000 <p>This study examines the steady flow of an electrically conducting fluid through a rotating porous channel bounded by stationary, impermeable horizontal plates at constant temperature. The primary aim is to explore the combined effects of a magnetic field, wall slip conditions, and viscous dissipation. The channel rotates at a constant angular velocity, with slip conditions applied at the walls. A pressure gradient drives the primary flow, while rotation generates the secondary flow. Analytical solutions for velocity profiles and volumetric flow rates are obtained, and the temperature distribution is calculated using MATLAB's “bvp4c” function. The research offers novel insights into the behavior of primary and secondary flow velocities under different Hartmann and Taylor numbers, emphasizing the impact of slip conditions. Additionally, the influence of the Eckert number on temperature is analyzed in conjunction with these parameters. These findings contribute valuable theoretical perspectives for enhancing cooling systems in rotating machinery using conductive fluids in porous channels. This study opens avenues for future research to investigate unsteady flow conditions and the effects of variable magnetic fields and rotational speeds on fluid behavior in rotating porous channels.</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1562-1573"},"PeriodicalIF":2.8,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143379925","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}

引用次数: 0

Analysis of Hydrothermal Flow and Performance of Heat Transfer in 3D Pipes Based on Varying Dimple Structure Configurations 基于不同凹窝结构构型的三维管道热液流动及传热性能分析

IF 2.8

Heat Transfer Pub Date : 2024-12-02 DOI: 10.1002/htj.23244

Saad Raad Al-Haidari, Ahmed Ramadhan Al-Obaidi

{"title":"Analysis of Hydrothermal Flow and Performance of Heat Transfer in 3D Pipes Based on Varying Dimple Structure Configurations","authors":"Saad Raad Al-Haidari, Ahmed Ramadhan Al-Obaidi","doi":"10.1002/htj.23244","DOIUrl":"https://doi.org/10.1002/htj.23244","url":null,"abstract":"<div>\u0000 \u0000 <p>In the current work, the study examines the flow patterns and heat transfer capabilities of tubes with various spherical dimple configurations. A numerical analysis, supported by experimental validation on a reference model, was conducted on a circular tube with an alternating flow path. The primary goal was to enhance the thermal performance of circular tubes by inducing mixing and vortex flows. The impact of three design factors on thermal–hydraulic performance was investigated, dimple pipe diameter (DPD), dimple group number (DGN), and number of dimples (NODs). Dimpled tubes consistently outperformed smooth tubes in heat transfer due to increased flow mixing and separation. Both increasing the Reynolds number and decreasing the design factors led to the formation of mixing and vortex patterns. The performance evaluation factor (PEF) varied across different dimple configurations. For DPD, PEF ranged from 1.14 to 1.33; for DGN, it ranged from 1.15 to 1.28; for NOD, it ranged from 0.95 to 1.21, all within a Reynolds number range of 4000–15,000. At a Reynolds number of 6000, all three configurations of DPD, DGN, and NOD outperformed the smooth pipe in terms of the Nusselt number. For DPD, Nusselt number improvements ranged from 25.7% to 30.8%, and friction factors increased by 21% to 67%. DGN configurations exhibited a wider range of Nusselt number enhancement from 25% to 49.6%, and friction factor increase from 37% to 72%. NOD configurations also demonstrated consistent improvements, with Nusselt number increases ranging from 27.35% to 31% and friction factor increases from 42% to 74%. Spherical dimples can significantly enhance the thermal–hydraulic performance of tubes, so the best configuration depends on the specific application, and the highest performance, with a 1.33 increase in PEF, was achieved with a dimple diameter of 2 mm (DPD = 2 mm) and a dimple density of four dimples per unit area (NOD = 4).</p>\u0000 </div>","PeriodicalId":44939,"journal":{"name":"Heat Transfer","volume":"54 2","pages":"1589-1610"},"PeriodicalIF":2.8,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380225","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}

引用次数: 0