Applied Thermal Engineering最新文献

{"title":"Structural design and multi-criteria evaluation of refrigerant-based cold plate for battery thermal management system","authors":"Xue Gao ,&nbsp;Qing Gao","doi":"10.1016/j.applthermaleng.2025.126481","DOIUrl":"10.1016/j.applthermaleng.2025.126481","url":null,"abstract":"<div><div>Refrigerant-based cold plates (RCP) are increasingly attracting attention for their high heat transfer efficiency, robust thermal safety, and superior integration capabilities. This study introduces a RCP design with a variable-area runner (VAR) structure for battery thermal management system (BTMS). The impact of runner structure and flow boiling parameters on its performance is investigated from temperature control, energy consumption, and lightweight requirements through numerical simulations. It revealed that the sensitivity of runner structure parameters to temperature and energy consumption traits conflicted. Consequently, the performance evaluation index (PEI) is established to enhance the multi-criteria assessment of cold plates. The results showed that when<span><math><msub><mi>R</mi><mi>a</mi></msub></math></span> = 40 mm/1mm, <span><math><msub><mi>R</mi><mi>e</mi></msub></math></span>=0.0036, PEI = 1.2, the cold plate demonstrates optimal performance. Further analysis emphasizes the impact of flow boiling parameters on the optimal cold plate structure. Results indicated effective battery temperature control at 1C to 3C discharge rates. Cooling efficiency decreased as evaporation temperature increased from 10℃ to 22℃. Optimal temperature consistency achieved at the evaporation temperature of 16℃. Variation in refrigerant flow rates from 0.02 kg/s to 0.2 kg/s showed insignificant effects on cooling performance and energy consumption. Overall, this research provides new concepts for the design and evaluation of RCPs, enhances the comprehension of the influence of runner structure and flow boiling parameters on system performance, and offers insights for the implementation of BTMS.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"273 ","pages":"Article 126481"},"PeriodicalIF":6.1,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143838287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical investigation on the performance of a W-type radiant tube using ammonia/hydrogen/methane blends","authors":"Zhicheng Hao ,&nbsp;Fangguan Tan ,&nbsp;Jiaqiang Xu ,&nbsp;Xiaochen Hu ,&nbsp;Dengze Li ,&nbsp;Fashe Li ,&nbsp;Dongfang Li ,&nbsp;Hua Wang","doi":"10.1016/j.applthermaleng.2025.126498","DOIUrl":"10.1016/j.applthermaleng.2025.126498","url":null,"abstract":"<div><div>As crucial equipment in the metallurgical industry, radiant tubes possess significant CO₂ reduction potential. Ammonia/hydrogen/methane blends can mitigate the constraint associated with single-component carbon-free fuel/methane blends, facilitating a higher proportion of methane replacement. Although ammonia/hydrogen/methane blends are promising for the CO₂ reduction of radiant tubes, their effect on the performance of radiant tubes remains unclear. In this study, several cases with different NH₃/H₂/50%CH₄ fuel blend ratios are numerically performed to compare the effect of fuel components on the performance of the W-type radiant tube (WRT). Compared to 100 % CH₄, using NH₃/H₂/50%CH₄ blends in the WRT could enhance temperature uniformity and reduce CO₂ emissions significantly. However, this came with a decreased thermal efficiency and dramatically increased NO_x emissions. As the NH₃ proportion in NH₃/H₂/50%CH₄ blends decreased from 50 % to 25 %, H₂ increased from 0 % to 25 %, the temperature difference increased from 76.2 K to 81.4 K, the non-uniformity coefficient increased from 0.0555 to 0.0591, the thermal efficiency increased from 58.5 % to 59.9 %, the CO₂ emissions increased from 5.10 g/s to 5.28 g/s, and the NO concentration increased from 1725 ppm to 1954 ppm. This indicates that NH₃ in NH₃/H₂/50%CH₄ blends is crucial for enhancing temperature uniformity and reducing emissions, while H₂ importantly boosts thermal efficiency. In addition, although the use of NH₃/H₂/50%CH₄ blends slightly reduced the emissivity of the flue gas, it had no significant effect on the radiative heat transfer between the flue gas and the tube. Moreover, the greenhouse effect caused by N₂O was negligible.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"273 ","pages":"Article 126498"},"PeriodicalIF":6.1,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143844562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The thermal improvement of cascade phase change thermal management module for photovoltaic cells","authors":"Tingting Wu ,&nbsp;Lianjian Mo ,&nbsp;Yanxin Hu ,&nbsp;Changxiang Fan ,&nbsp;Mingjiang Zeng ,&nbsp;Shuting Cai ,&nbsp;Mengjie Song","doi":"10.1016/j.applthermaleng.2025.126486","DOIUrl":"10.1016/j.applthermaleng.2025.126486","url":null,"abstract":"<div><div>Most existing phase change thermal management technologies are uniformly filled phase change modules, resulting in a certain degree of suppression of their phase change heat absorption rate, which seriously hampers the development and application of phase change material (PCM) in thermal management systems for photovoltaic cells. In this regard, a cascade phase change thermal management module for photovoltaic cells was proposed, where paraffin (PA) was used as the phase change matrix, polyethylene octene co-elastomers (POE) and ethylene-ethylene-butadiene-styrene block copolymers (SEBS) were employed as flexible support materials, and expansion graphite (EG) and carbon nanotubes (CNTs) were utilized as thermally conductive reinforcing materials to synergistically improve the thermal conductivity of the materials, resulting in the preparation of a highly thermally conductive flexible phase change material (SCPCM). The experimental results showed that the maximum thermal conductivity of SCPCM was 1.217 W/(m·K) at a mass fraction of 4 % of EG and 1 % of CNTs, and its latent heat of phase change was 150 J/g. It was also flexible and able to meet the thermal management requirements of photovoltaic cells. In addition, under the simulated sensible heat power of 2000 W/m² irradiation intensity, after coupling a 10 mm phase change layer, the phase change layer of the cascade structure had the most excellent cooling effect, and the maximum temperature was reduced by 4.4 °C.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"273 ","pages":"Article 126486"},"PeriodicalIF":6.1,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143833753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel solid oxide electrolysis cell system thermally integrated with the Haber–Bosch process","authors":"Jongyun Jung ,&nbsp;Seunghun Oh ,&nbsp;Siwoong Kim ,&nbsp;Taebeen Kim ,&nbsp;Sanggyu Kang","doi":"10.1016/j.applthermaleng.2025.126489","DOIUrl":"10.1016/j.applthermaleng.2025.126489","url":null,"abstract":"<div><div>A solid oxide electrolysis cell (SOEC) system thermally integrated with Haber-Bosch (HB) process is a potential solution for improving the hydrogen and ammonia economies in terms of production, storage, and transportation. By utilizing waste heat from the HB process to generate steam for the SOEC system, overall system efficiency for green ammonia production can be improved. In this study, numerical model of the SOEC–HB hybrid system is developed using Aspen Plus®. The SOEC model is validated by comparing the current density–voltage polarization curves obtained for various stack temperatures and hydrogen inlet mole fractions with the experimental data. To confirm the superiority of proposed SOEC–HB hybrid system, its efficiency is compared to that of the arithmetic summation of the SOEC and HB systems without thermal integration. To optimize the operating conditions for the proposed hybrid system, parametric analysis is conducted by varying the operating parameters, including the SOEC stack operating temperature, current density, steam utilization, stack outlet hydrogen mole fraction, HB reactor (HBR) outlet temperature, and hydrogen-to-nitrogen ratio (HTNR). Compared to the SOEC-HB system without thermal integration, the overall efficiency of SOEC–HB hybrid system increases by 3.33 % under nominal conditions of operating temperature of SOEC stack of 700 °C, a current density of 1.0 A/cm², a steam utilization of 50 %, hydrogen mole fraction of 20 mol.%, an outlet temperature of HBR of 427 °C and a HTNR of 3.0. This improvement is attributed to the reduction in heat consumption by the vaporizer.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"273 ","pages":"Article 126489"},"PeriodicalIF":6.1,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143844566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring conjugate heat transfer in Bingham fluid flow: A 3D computational approach incorporating double diffusion and the Papanastasiou model","authors":"Shafee Ahmad ,&nbsp;Dong Liu ,&nbsp;Bai Mbye Cham ,&nbsp;Song Yang ,&nbsp;Si-Liang Sun","doi":"10.1016/j.applthermaleng.2025.126500","DOIUrl":"10.1016/j.applthermaleng.2025.126500","url":null,"abstract":"<div><div>In this study, double diffusion and conjugate heat transfer are adopted to examine the factors affecting the heat and mass transfer on the performance and durability of many electronic devices such as light-emitting diode (LED). The non-linear rheology of Bingham fluid, utilizing the Papanastasiou model to manage yield stress discontinuities, is investigated inside a cubical enclosure. A solid vertical plate with slab fins is considered to be heated externally, playing the role of an LED base plate. A collection of non-linear differential equations simulates the physical phenomenon. A promising tool, the finite element scheme is utilized for computations which is first validated with experimental and numerical data. Optimization of computational cast reveals that three-dimensional (3D) result depicts the best structural visualization but it is much more costly than two-dimensional (2D). The non-Newtonian behaviour shows that heat and mass fluxes decrease with yield number (<em>y_t</em>) and the maximum is obtained in the case of Newtonian materials. The thermal energy transport increases with both thermal conductivity ratio (<em>R_k</em>) and plate thickness (<em>x_p</em>). Increasing the Rayleigh number (<em>Ra</em>) increases the shear rate and unyielded region diminishes near the fins, leading to promoted convection. It is noticed that Soret (<em>S_r</em>) and Dufour (<em>D_f</em>) parameters have positive impacts on heat and mass transfer rates. Results show that mass flow rate rises with Lewis number (<em>Le</em>) while the opposite trend is seen in heat transmission. The influence of <em>Ha</em> reveals that heat and mass transfer rates are maximum in the absence of magnetic fields. The relative change of mean Nusselt number (<em>Nu_avg</em>) is low at the beginning and rises with <em>Ha</em>, attens the maximum decrease at <em>Ha</em> = 60.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"273 ","pages":"Article 126500"},"PeriodicalIF":6.1,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal and hydraulic performance of caseless, pinless and gasket-free spiral plate heat exchanger","authors":"Mohammed Kamil ,&nbsp;Ahmad Alobaid ,&nbsp;Salah Kayed ,&nbsp;Mahmoud Attia Abouelazm ,&nbsp;Amir Hakim","doi":"10.1016/j.applthermaleng.2025.126480","DOIUrl":"10.1016/j.applthermaleng.2025.126480","url":null,"abstract":"<div><div>Heat exchangers are fundamental components across numerous industries, contributing significantly to efficiency and thermal performance by facilitating the transfer of heat between fluids. Optimizing their effectiveness and thermal performance remains a key objective. This study introduces a novel design for spiral plate heat exchangers (SPHEs), addressing limitations in conventional designs through significant structural modifications. A new SPHE design tailored for specific heat exchange duties was developed, overcoming several challenges of traditional configurations. This design was translated into a physical model and subjected to extensive evaluation. A computational fluid dynamics (CFD) model was also developed to provide deeper insights into the thermal dynamics of the SPHE system, with the model validated using experimental data collected from a purpose-built test rig integrated with the new SPHE. Experimental studies were conducted to evaluate the thermal and hydraulic performance of the new SPHE compared to conventional designs. Key parameters examined included the Reynolds number (Re), ranging from 1000 to 2400, and the hot liquid inlet temperature, varying from 80 °C to 50 °C. Thermal performance metrics showed notable improvements with the new SPHE design, achieving average increases of 28 % in heat exchange rate, 6.75 % in effectiveness, 17.3 % in the number of transfer units (NTU), and 35.3 % in the Biot number (Bi). Hydraulically, the new design demonstrated superior performance, with average reductions of 32.1 % in pressure drops and corresponding improvements of 32.1 % in the Euler number and 61 % in the Jensen number. These results highlight substantial advancements in the thermal and hydraulic efficiency of the proposed SPHE, coupled with improvements in structural design and manufacturing processes. Future research is recommended to evaluate the new design in specific applications, such as district cooling systems and energy conversion and storage systems, to further validate its advantages under practical operating conditions.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"273 ","pages":"Article 126480"},"PeriodicalIF":6.1,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143833751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A review on thermal collection management and conversion performance enhancement of extended range electric vehicle exhaust thermoelectricity","authors":"Xiaohuan Zhao ,&nbsp;Jiawei Yin ,&nbsp;Jiang Jiang ,&nbsp;Ruoxin Lan ,&nbsp;Jie Wang ,&nbsp;D. Zhao","doi":"10.1016/j.applthermaleng.2025.126476","DOIUrl":"10.1016/j.applthermaleng.2025.126476","url":null,"abstract":"<div><div>Thermal energy conversion and management have consistently been the focus of energy conservation and emission reduction in automobile fields. The exhaust heat from extended range electric vehicles can be utilized to generate electricity, which is then stored in the onboard energy storage battery for the vehicle. This study illustrates thermal collection management and conversion performance enhancement. The system constructions, energy conversation work principle and advantages for fuel savings and emission reduction are introduced. Approaches for thermal energy efficiency collection enhancement and conversion performance improvement methods are presented. The material and structure, temperature difference change, multi-physics model and maximum power point tracking technology can enhance the thermal energy collection. The maximum output power of extended range electric vehicle experiment can be increased from 12.41 to 1002.6 W with the thermoelectric generator number changes. The simulation model can enhance the output performance by up to 35 %. The efficiency of the extended range electric vehicle exhaust thermoelectric materials system is 48 % when the thermoelectric figure of merit value is 2.4. The thermoelectric efficiency can be improved by 76 % of 3 cascades in uni-leg systems, which can improve fuel economy of the vehicle.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"273 ","pages":"Article 126476"},"PeriodicalIF":6.1,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143833631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal management of hairpin winding traction motors in electric vehicles: Parametric evaluation of impinging oil jet cooling using CFD simulations","authors":"Waruna Maddumage ,&nbsp;Safouene Ouenzerfi ,&nbsp;Souad Harmand ,&nbsp;Alasdair Cairns ,&nbsp;Amin Paykani","doi":"10.1016/j.applthermaleng.2025.126414","DOIUrl":"10.1016/j.applthermaleng.2025.126414","url":null,"abstract":"<div><div>Efficient thermal management is critical for ensuring the performance and longevity of high-power-density electric traction motors, particularly those using hairpin windings. This study aims to address the challenges of localised cooling in such systems by characterising oil jet impingement cooling using computational fluid dynamics (CFD) simulations. A detailed geometric model of hairpin windings was implemented to capture fluid-winding interactions within a 45-degree sector of the motor end winding region. The study examines key design parameters affecting cooling performance through a parametric analysis, including nozzle geometry (diameter, orientation, and distance), mounting configuration, and operational conditions (flow rate and inlet velocity). The numerical model demonstrated good agreement with experimental data, particularly in predicting heat transfer coefficient trends across different flow conditions. Results revealed that axial configurations with 2 mm nozzle diameters achieved higher heat transfer performance (940 W/m²K at 0.75 kg/min) compared to radial configurations, though this performance showed sensitivity to operational parameters. Additionally, critical velocity thresholds were identified, marking transitions between gravity-dominated and momentum-driven heat transfer mechanisms, with optimal nozzle orientations varying accordingly. Both top-mounted and radially mounted nozzle configurations were studied, with top-mounted configurations demonstrating superior spatial cooling distribution, achieving up to 370<span><math><mtext>%</mtext></math></span> enhancement in adjacent winding cooling at higher angular positions. These findings provide practical design guidelines for implementing efficient jet cooling systems in high-performance electric traction motors, particularly for optimising multi-nozzle array configurations to achieve effective thermal management.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"273 ","pages":"Article 126414"},"PeriodicalIF":6.1,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143833633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical simulation and sensitivity analysis of hot air drying for irregular flake materials based on fully coupled of multi-physics fields","authors":"Hao Zhang,&nbsp;Lihua Wang,&nbsp;Wei Jiang,&nbsp;Zemin Zhao,&nbsp;Qike Wei,&nbsp;Huaiyu Wang","doi":"10.1016/j.applthermaleng.2025.126449","DOIUrl":"10.1016/j.applthermaleng.2025.126449","url":null,"abstract":"<div><div>The multi-physics coupling mechanisms of irregular flake materials during hot air drying remain unclear. Therefore, a three-dimensional thermal-mass-mechanical bidirectional fully coupled model was established in this study, incorporating shrinkage deformation, dynamic porosity variations, and their feedback effects on heat and mass transfer. The model’s accuracy was validated through experiments, systematically revealing the spatially asymmetric distribution characteristics of temperature-moisture fields and stress–strain fields in materials of different sizes, along with their dynamic evolution patterns associated with structural features. The interaction mechanisms between material dimensions and drying parameters were elucidated. Sensitivity analysis using the OAT method quantified the influence of key parameters on the drying process. The research demonstrates that small-sized materials exhibit uniform thermal-moisture distribution and low stress–strain characteristics due to their high specific surface area and short mass transfer paths, while large-sized materials show significantly increased thermal and moisture stresses with stress concentration prone to occur at concave regions. Moisture stress dominates shrinkage deformation, showing positive correlations with both material size and temperature. Material size exerts a more pronounced influence on drying efficiency compared to temperature. Sensitivity analysis reveals that small-sized materials demonstrate significantly higher sensitivity to external parameters than large-sized ones, while large-sized materials are more affected by Poisson’s ratio and thermal conductivity. Young’s modulus regulates stress states but shows no correlation with the timing of stress peaks. The study further proposes separating small-sized materials from medium/large ones during drying processes, and optimizing drying temperature and mass transfer conditions to balance porosity changes with stress concentration, thereby enhancing drying uniformity. This research provides theoretical support from a multi-physics coupling perspective for optimizing drying processes, inhibiting shrinkage deformation, and improving product quality, offering practical guidance for relevant industrial applications.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"273 ","pages":"Article 126449"},"PeriodicalIF":6.1,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143829697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of varying passive interrupted geometrical techniques to implement novel parametric assessment of improving thermal-hydraulic performance in 3D pipe","authors":"Ahmed Ramadhan Al-Obaidi","doi":"10.1016/j.applthermaleng.2025.126471","DOIUrl":"10.1016/j.applthermaleng.2025.126471","url":null,"abstract":"<div><div>This study investigates the hydrodynamic and thermal performance of pipes incorporating passive geometric modifications, focusing on optimizing fluid flow dynamics and heat transfer efficiency. A computational analysis evaluates turbulent flow behavior and heat exchange in three-dimensional pipe geometries under constant heat flux conditions, spanning Reynolds numbers from 1000 to 14,000. The research employs a single-phase, water-based thermo-hydrodynamic framework to assess Insert Twisted Tape (ITT), Corrugated Ring Diameter (CRD), and Dimple Surface Diameter (DSD) pipe configurations. Results indicate that the maximum difference between the numerical simulations and the empirical equations for Nu is 7.9%. Similarly, the maximum difference in the friction factor (f) between the two approaches is 6.5 %. Also, using different passive geometric designs significantly enhance the Nusselt number (Nu) and overall thermal performance compared to smooth pipes. Structural modifications induce secondary vortical flows and amplify turbulence, disrupting thermal boundary layers and improving heat transfer. Performance evaluation criteria exceeding unity confirm the superiority of these geometries over conventional smooth channels. In addition to enhancing heat transfer rates, the study highlights the impact of passive geometric configurations on pressure drop and energy consumption. While dimpled and corrugated designs exhibit superior heat transfer capabilities, they also generate higher pressure drops due to increased surface roughness and fluid interaction. However, the substantial thermal performance improvement often compensates for the additional pumping power required. A comparative performance analysis based on the overall thermal performance factor (PEF) of the evaluated geometries indicates that the dimpled surface design (DSD) achieved the highest PEF value of approximately 1.8. The corrugated (CRD) and twisted tube (ITT) configurations followed, with PEF values of 1.77 and 1.61, respectively. The study concludes that selecting the most suitable configuration depends on the desired balance between thermal enhancement and energy expenditure, with dimpled designs being the most effective in scenarios prioritizing heat transfer.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"273 ","pages":"Article 126471"},"PeriodicalIF":6.1,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}